Acquisitions And Dispositions [Abstract] Acquisitions and Dispositions Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Other Businesses [Member] Other Businesses [Member] Other Businesses [Member] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Trade name [Member] Trade Names [Member] Other [Member] Other Intangible Assets [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Student and Customer Relationships [Member] Customer Relationships [Member] Trade Names and Trademarks [Member] Trademarks and Trade Names [Member] Databases and Technology [Member] Database Rights [Member] Non-compete Agreements [Member] Noncompete Agreements [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Hoover Treated Wood Products [Member] Hoover Treated Wood Products [Member] Hoover Treated Wood Products [Member] Red Marker [Member] Red Marker [Member] Red Marker [Member] 2016 Acquisitions [Member] Current Year Acquisitions [Member] Current year acquisitions [Member] Series of Individually Immaterial Business Acquisitions [Member] Series of Individually Immaterial Business Acquisitions [Member] Genesis [Member] Genesis [Member] Genesis [Member] Hometown Home Health and Hospice [Member] Hometown Home Health and Hospice [Member] Hometown Home Health and Hospice Business Acquisition [Line Items] Business Acquisition [Line Items] Cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Inventory Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory Property, plant and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Goodwill Goodwill Indefinite-lived intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets Amortized intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Assets Amount of other assets acquired at the acquisition date. Pension and other post retirement benefits liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Pension and Other Post Retirement Benefits Liabilities Amount of pension and postretirement liabilities assumed at the acquisition date. Other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Deferred income tax liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Redeemable noncontrolling interest Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value Aggregate purchase price, net of cash received Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest, Net Of Cash Received Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree, net of cash received. Investments in Affiliates Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Investments In Affiliates Subsidiaries Associates And Joint Ventures Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership, acquired at the acquisition date. Other noncurrent assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Current liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities Noncurrent liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Total Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest Weighted Average Life (in years) Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Retirement Benefits, Description [Abstract] Pension and Postretirement Plans Pension and Other Postretirement Benefits Disclosure [Text Block] Accounting Policies [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Prior Period Adjustments [Axis] Prior Period Adjustments [Axis] -- None. No documentation exists for this element. -- Prior Period Adjustments [Domain] Prior Period Adjustments [Domain] -- None. No documentation exists for this element. -- Periods from 2011 to Q2 2015 [Member] Periods from 2011 to Q2 2015 [Member] Periods from 2011 to Q2 2015 [Member] Subsegments [Axis] Subsegments [Axis] Subsegments [Domain] Subsegments [Domain] Higher Education [Member] Higher Education [Member] Higher Education [Member] Test Preparation [Member] Test Preparation [Member] Test Preparation [Member] Kaplan International [Member] Kaplan International [Member] Kaplan International [Member] Kaplan Corporate and Other [Member] Kaplan Corporate and Other [Member] Kaplan Corporate And Other [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] Non U.S. [Member] Non-US [Member] UNITED KINGDOM UNITED KINGDOM Segments [Axis] Television Broadcasting [Member] Television Broadcasting [Member] Television Broadcasting [Member] Education [Member] Education [Member] Education [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Kaplan China [Member] Kaplan China [Member] Kaplan China [Member] KHE Campuses [Member] KHE Campuses [Member] KHE Campuses [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Software asset write-offs RestrucuturingSoftwareAssetWriteoffs Restructuring costs associated with software asset write-offs. Immaterial Error Correction Amount Immaterial Error Correction Amount Amount of effect on financial statements related to corrections of prior period errors in the current period financial statements when the effect of the prior period error was immaterial to the prior period financial statements and the current period correction is immaterial to the current period financial statements. Number of reportable segments Number of Reportable Segments Number of schools sold Number Of Schools Sold The number of schools sold. Restructuring costs Restructuring Charges Number of campuses announced to close or consolidate Number Of Campuses Announced To Close Or Consolidate Number of campuses announced to close or consolidate Number of nationally accredited ground campuses sold Number Of Nationally Accredited Ground Campuses Sold The number of nationally accredited ground campuses sold. Other long-lived assets impairment charge Tangible Asset Impairment Charges Accrued restructuring costs Restructuring Reserve Number of television broadcast stations owned Number Of Television Broadcast Stations Owned Number of television broadcast stations owned by the Company. Operating Revenues Revenues Foreign assets Entity Wide Disclosure On Geographic Areas Long-Lived Assets Excluding Goodwill And Other Intangible Assets In Foreign Countries Amount of long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets, goodwill, and other intangible assets located in foreign countries in total in which the entity holds assets. Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward] Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward] Fair value of assets at beginning of year Defined Benefit Plan, Fair Value of Plan Assets Purchases, sales and settlements, net Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Purchases, Sales, and Settlements Gains relating to assets sold Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Actual Return (Loss) on Plan Assets Sold Gains relating to assets still held at year-end Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Actual Return (Loss) on Plan Assets Still Held Fair value of assets at end of year Capital Stock, Stock Awards, and Stock Options [Abstract] -- None. No documentation exists for this element. -- Schedule of Earnings Per Share, Basic and Diluted, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic and Diluted, Including Two Class Method [Table] Disclosures pertaining to an entity's basic and diluted earnings per share. Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Employee Stock Option [Member] Employee Stock Option [Member] Schedule of Earnings Per Share, Basic and Diluted, Including Two Class Method [Line Items] Schedule of Earnings Per Share, Basic and Diluted, Including Two Class Method [Line Items] [Line Items] for Disclosures pertaining to an entity's basic and diluted earnings per share. Income (loss) from continuing operations attributable to Graham Holdings Company common stockholders Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Less: Dividends paid–common stock outstanding and unvested restricted shares Dividends Paid Common Stock And Share-based Compensation-Cash Amount of paid and unpaid common stock dividends declared with the form of settlement in cash and amount of paid and unpaid cash dividends declared and applicable to holders of share-based compensation, for example, but not limited to, non-vested shares, stock options, or restricted stock units. Undistributed earnings (losses) Undistributed Earnings, Basic Percent allocated to common stockholders (1) Percentage Of Undistributed Earnings Allocated To Common Stockholders Represents the percentage allocation of undistributed earnings to common stockholders. Undistributed earnings (losses) allocated to common stockholders Undistributed Earnings Allocated To Common Stockholders The earnings that is allocated to common stock to the extend that each stockholder may share in the earnings as if all the earnings for the period has been distributed. Add: Dividends paid–common stock outstanding Dividends, Common Stock, Cash Numerator for basic earnings (loss) per share Basic income from continuing operations attributable to common stockholders The earnings that is allocated to common stock as if all of the earnings for the period had been distributed. Add: Additional undistributed earnings due to dilutive stock options Additional Undistributed Earnings Due To Dilutive Stock Options The earnings that is allocated to common stock due to the dilutive effect of stock options in diluted earnings per share. Numerator for diluted earnings (loss) per share Net Income (Loss) Available to Common Stockholders, Diluted Denominator for basic earnings (loss) per share (shares) Weighted Average Number of Shares Outstanding, Basic Add: Effect of dilutive stock options (shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Denominator for diluted earnings (loss) per share (shares) Weighted Average Number of Shares Outstanding, Diluted Income Per Share From Continuing Operations To Common Stockholders [Abstract] Income Per Share From Continuing Operations To Common Stockholders [Abstract] Income Per Share From Continuing Operations To Common Shareholders. Basic income (loss) per common share from continuing operations in dollars per share Income (Loss) from Continuing Operations, Per Basic Share Diluted income (loss) per common share from continuing operations in dollars per share Income (Loss) from Continuing Operations, Per Diluted Share Antidilutive Shares [Abstract] Antidilutive Shares [Abstract] Antidilutive Restricted Stock Antidilutive Restricted Stock Additional shares excluded in the calculation of diluted EPS as a result of the antidilutive effect of restricted stock using the treasury stock method. Antidilutive Options Antidilutive Options Additional shares excluded in the calculation of diluted EPS as a result of the antidilutive effect of options using the treasury stock method. Quarterly Financial Information Disclosure [Abstract] Operating Revenues Revenues [Abstract] Education Education revenue Revenues from a range of education and related services worldwide for students, professionals and other organizations. Advertising Advertising Revenue Other Other Revenue, Net Total Operating Revenues Operating Costs and Expenses Operating Costs and Expenses [Abstract] Operating Operating Expense Generally recurring costs associated with normal operations including the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes selling, general and administrative expenses. Selling, general and administrative Selling, General and Administrative Expense Depreciation of property, plant and equipment Depreciation Amortization of Intangible Assets Amortization of Intangible Assets Impairment of goodwill and other long-lived assets Asset Impairment Charges Impairment of Goodwill Goodwill, Impairment Loss Total Operating Costs and Expenses Costs and Expenses Income (Loss) from Operations Operating Income (Loss) Equity in losses of affiliates, net Income (Loss) from Equity Method Investments Interest Income Investment Income, Interest Interest expense Interest Expense Non-operating pension and postretirement benefit income, net Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component Amount of expense (reversal of expense) for net periodic benefit cost components, excluding service cost component, of defined benefit plan. Amount includes, but is not limited to, interest cost, expected (return) loss on plan asset, amortization of prior service cost (credit), amortization of (gain) loss, amortization of transition (asset) obligation, settlement (gain) loss, curtailment (gain) loss and certain termination benefits. Other income (expense), net Other Nonoperating Income (Expense) Income (Loss) from Continuing Operations Before Income Taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest (Benefit from) Provision for Income Taxes Income Tax Expense (Benefit) Net Income (Loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Income (Loss) from Continuing Operations Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Income from Discontinued Operations, Net of Tax Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Net (Income) Loss Attributable to Noncontrolling Interests Income (Loss) Attributable to Redeemable Noncontrolling Interest and Nonredeemable Noncontrolling Interest Amount of Net Income (Loss) attributable to redeemable noncontrolling interest and nonredeemable noncontrolling interest. Net (Income) Loss Attributable to Noncontrolling Interests Net Income (Loss) Attributable to Noncontrolling Interest Net Income (Loss) Attributable to Graham Holdings Company Net Income (Loss) Attributable to Parent Redeemable Preferred Stock Dividends Redeemable Preferred Stock Dividends Net Income (Loss) Attributable to Graham Holdings Company Common Stockholders Net Income (Loss) Available to Common Stockholders, Basic Amounts Attributable to Graham Holdings Company Common Stockholders Income Amounts Attributable to Parent, Disclosures [Abstract] Income (loss) from continuing operations Per Share Information Attributable to Graham Holdings Company Common Stockholders Earnings Per Share [Abstract] Basic income per common share from discontinued operations in dollars per share Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share Basic net income (loss) per common share in dollars per share Earnings Per Share, Basic Basic average number of common shares outstanding in shares Diluted income per common share from discontinued operations in dollars per share Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share Diluted net income (loss) per common share in dollars per share Earnings Per Share, Diluted Diluted average number of common shares outstanding in shares Weighted Average Number Of Potentially Dilutive Shares Outstanding The weighted average number of shares outstanding that could potentially dilute basic EPS. Comprehensive Income (Loss), Net of Tax, Attributable to Parent Comprehensive Income (Loss), Net of Tax, Attributable to Parent Commitments and Contingencies Disclosure [Abstract] Loss Contingencies [Table] Loss Contingencies [Table] Transaction [Axis] Transaction [Axis] Transaction [Axis] Transaction Type [Domain] Transaction Type [Domain] Transaction Type [Domain] Sale Of KHE Campuses Business [Member] Sale Of KHE Campuses Business [Member] Sale of KHE Campuses business [Member] KHE's Broomall, PA location [Member] K H Es Broomall P A Location [Member] KHE's Broomall, PA location [Member] Kaplan University [Member] Kaplan University [Member] -- None. No documentation exists for this element. -- UK Pathways [Member] UK Pathways [Member] UK Pathways [Member] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Urquilla-Diaz And Jajdelski Case [Member] Urquilla-Diaz And Jajdelski Cases [Member] United States of America ex rel. Carlos Urquilla-Diaz et al. v. Kaplan University et al. (unsealed March 25, 2008) and United States of America ex rel. Charles Jajdelski v. Kaplan Higher Education Corp. et al. (unsealed January 6, 2009). [Member] Diaz Case [Member] Diaz Case [Member] United States of America ex rel. Carlos Urquilla-Diaz et al. v. Kaplan University et al., included three separate complaints: Diaz, Wilcox and Gillespie. Diaz Claims [Member] Diaz Claims [Member] Diaz claims included in the United States of America ex rel. Carlos Urquilla-Diaz et al. v. Kaplan University et al. complaint. [Member] Jajdelski case [Member] Jajdelski Case [Member] -- None. No documentation exists for this element. -- Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Investment, Name [Axis] Investment, Name [Axis] Investment, Name [Domain] Investment, Name [Domain] Celtic Healthcare Allegheny Health Network Joint Venture [Member] CelticHealthcareAlleghenyHealthNetworkJointVenture [Member] A joint venture formed between Celtic Healthcare and Allegheny Health Network Income Tax Authority, Name [Axis] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Income Tax Authority, Name [Domain] Her Majesty's Revenue and Customs (HMRC) [Member] Her Majesty's Revenue and Customs (HMRC) [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Number of existing legal claims or proceedings that are likely to have a material effect on the Company's business Loss Contingency, Pending Claims, Number Loss contingency, estimate of possible loss Loss Contingency, Estimate of Possible Loss Amount payable under agreement Litigation Settlement, Amount Awarded to Other Party Number of unsealed cases filed by former employees under the U.S. Federal False Claims Act Number Of Unsealed Cases Filed By Former Employees Under U S Federal False Claims Act Number of unsealed cases filed by former employees under the U.S. Federal False Claims Act The number of separate complaints included in the Diaz case that received rulings Separate Complaints Included In A Series Of Rulings On Number of separate complaints included in the Diaz case that the U.S. District Court for the Southern District of Florida issued a series of rulings on. Remaining employment claim in the Diaz complaint Remaining Employment Claim In The Diaz Complaint Number of remaining employment claim in the Diaz complaint with the U.S. District Court for the Southern District of Florida. Number of claims affirmed for dismissal by US Court of Appeals Number Of Claims Affirmed For Dismissal by US Court of Appeals Number of claims affirmed for dismissal by the U.S. Court of Appeals for the Eleventh Judicial Court. Number of claims appealed Number of Claims Appealed Number of claims appealed to and heard by the U.S. Court of Appeals for the Eleventh Judicial Court. Number of allegations not dismissed Number Of Dismissed Allegations Reversed By The US Circuit Court For The Ninth Judicial Circuit Number of dismissed allegations reversed by the U.S. Circuit Court for the Ninth Judicial Circuit. Number of conditions out of compliance Number Of Conditions Out Of Compliance The number of conditions out of compliance. Number of days of noncompliance Number Of Days Of Noncompliance The number of days of noncompliance. Amount of penalties per day or per instance of noncompliance Amount Of Penalties Per Day Or Per Instance Of Noncompliance The amount of penalties per day or per instance of noncompliance. Deferred Charges and Other Assets Other Assets, Noncurrent Amount Of Estimated Unreturned Title IV Funds From Prior Periods Amount Of Estimated Unreturned Title IV Funds From Prior Periods Amount of estimated unreturned Title IV funds from prior periods. Education division revenue derived from financial aid received by students under Title IV programs Education Division Revenue Derived From Financial Aid Received By Students Under Title I V Programs Education division revenue derived from financial aid received by students under Title IV programs Number of pending ED program reviews Number of pending program reviews Number of pending program reviews. Portion of regulations under 90/10 rule Portion Of Regulations Under Ninety Ten Rule Portion of regulations under 90/10 rule Percentage of receipts from Title IV programs Percentage Of Receipts From Title IV Programs Percentage of receipts from Title IV programs. Percentage of receipts derived from Title IV Percentage Of Receipts Derived From Title I V Percentage of receipts derived from Title IV Discontinued Operation, Additional Disclosures [Abstract] Discontinued Operations Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Advertising Revenue [Member] Advertising Revenue [Member] Advertising Revenue [Member] Other revenue [Member] Other revenue [Member] Other revenue [Member] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Machinery and Equipment [Member] Machinery and Equipment [Member] Building [Member] Building [Member] Graham Healthcare Group [Member] Graham Healthcare Group [Member] Graham Healthcare Group [Member] Summary of Significant Accounting Policies [Line Items] Summary of Significant Accounting Policies [Line Items] -- None. No documentation exists for this element. -- Prior Period Reclassification Adjustment Prior Period Reclassification Adjustment Investment maturity length Investment Maturity Length For Classification As Cash And Cash Equivalents Investment maturity length for classification as cash and cash equivalents. Maximum amount of time between receipt and application of Federal aid funds Amount Of Time Between Receipt And Application Of Funds, Maximum The maximum amount of time between receipt of Federal aid funds and application to eligible student charges. Property, Plant and Equipment, Useful Life (in years) Property, Plant and Equipment, Useful Life Amortized Intangible Assets, Useful Life (in years) Finite-Lived Intangible Asset, Useful Life Noncontrolling Interest, Ownership Percentage by Parent Noncontrolling Interest, Ownership Percentage by Parent Investments [Abstract] Investments Investment [Text Block] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Pension Plans [Member] Pension Plan [Member] Supplemental Executive Retirement Plan (SERP) [Member] Supplemental Employee Retirement Plan [Member] Other Postretirement Plans [Member] Other Postretirement Benefits Plan [Member] 2018 Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months 2019 Defined Benefit Plan, Expected Future Benefit Payment, Year Two 2020 Defined Benefit Plan, Expected Future Benefit Payment, Year Three 2021 Defined Benefit Plan, Expected Future Benefit Payment, Year Four 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Five 2023-2027 Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter Other Nonoperating Income (Expense) [Abstract] Other Non-Operating (Expense) Income Other Income and Other Expense Disclosure [Text Block] Basis of Presentation and Principles of Consolidation Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block] Reclassifications Reclassification, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Business Combinations Business Combinations and Other Purchase of Business Transactions, Policy [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Unrestricted Cash and Cash Equivalents, Policy [Policy Text Block] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Concentration of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Allowance for Doubtful Accounts Trade and Other Accounts Receivable, Policy [Policy Text Block] Investments in Marketable Equity Securities Marketable Securities, Policy [Policy Text Block] Fair Value Measurements Fair Value Measurement, Policy [Policy Text Block] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Inventories and Contracts in Progress Inventory, Policy [Policy Text Block] Property, Plant and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Evaluation of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Goodwill and Other Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Investments in Affiliates Equity Method Investments [Policy Text Block] Cost Method Investments Cost Method Investments, Policy [Policy Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Leases Lessee, Leases [Policy Text Block] Pensions and Other Postretirement Benefits Pension and Other Postretirement Plans, Pensions, Policy [Policy Text Block] Self-Insurance Self Insurance Reserve [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Foreign Currency Translation Foreign Currency Transactions and Translations Policy [Policy Text Block] Equity-Based Compensation Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Mandatorily Redeemable Noncontrolling Interest Mandatorily Redeemable Noncontrolling Interest [Policy Text Block] Mandatorily Redeemable Noncontrolling Interest [Policy Text Block] Redeemable Noncontrolling Interest Redeemable Noncontrolling Interest [Table Text Block] Comprehensive Income Comprehensive Income, Policy [Policy Text Block] Discontinued Operations Discontinued Operations, Policy [Policy Text Block] Recently Adopted and Issued Accounting Pronouncemets New Accounting Pronouncements, Policy [Policy Text Block] Inventories and Contracts in Progress [Abstract] Inventories and Contracts in Progress [Abstract] Schedule of Inventories and Contracts in Progress [Table Text Block] Schedule of Inventory, Current [Table Text Block] Property, Plant and Equipment [Abstract] Property, Plant and Equipment Property, Plant and Equipment Disclosure [Text Block] Raw materials Inventory, Raw Materials, Net of Reserves Work-in-process Inventory, Work in Process, Net of Reserves Finished goods Inventory, Finished Goods, Net of Reserves Contracts in Progress Inventory for Long-term Contracts or Programs, Gross Inventories and contracts in progress Inventory, Net of Allowances, Customer Advances and Progress Billings Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Forney [Member] Forney [Member] Forney [Member] Goodwill [Line Items] Goodwill [Line Items] Asset Impairment Charges Number of businesses recorded impairment of goodwill Number Of Businesses Recorded Impairment Of Goodwill The number of businesses that recorded impairment of goodwill. Goodwill, Impairment Loss Goodwill and Intangible Asset Impairment Goodwill and Intangible Asset Impairment Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Interest Costs Capitalized Interest Costs Capitalized Property plant and equipment impairment charges Leases And Other Commitments [Abstract] -- None. No documentation exists for this element. -- Leases and Other Commitments Commitments Disclosure [Text Block] Debt Disclosure [Abstract] Debt [Table] Debt [Table] Schedule of all debt, including both short term and long term. Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] 7.25% Unsecured Notes due February 1, 2019 [Member] Seven Point Two Five Percent Unsecured Notes Due February One Two Thousand And Nineteen [Member] Seven Point Two Five Percent Unsecured Notes due February One, Two Thousand and Nineteen [Member] Kaplan Four Year Credit Agreement Dated July 14, 2016 [Member] Kaplan Four Year Credit Agreement Dated July 14, 2016 [Member] Kaplan Four Year Credit Agreement Dated July 14, 2016 [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Unamortized Debt Issuance Expense Unamortized Debt Issuance Expense Unsecured notes Unsecured Debt Line of Credit Long-term Line of Credit Other indebtedness Other Long-term Debt Total Debt Debt, Long-term and Short-term, Combined Amount Less: current portion Debt, Current Total Long-Term Debt Long-term Debt, Excluding Current Maturities Schedule of Restructuring Costs Restructuring and Related Costs [Table Text Block] Summary of Segment Reporting Information, by Operating Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Acquisitions and Dispositions of Businesses Mergers, Acquisitions and Dispositions Disclosures [Text Block] Income Tax Disclosure [Abstract] Deferred Income Tax Liabilities [Table] Deferred Income Tax Liabilities [Table] Deferred Income Tax Liabilities [Table] Pension Plan [Member] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] non-U.S. [Member] Foreign Tax Authority [Member] U.S. Federal [Member] Domestic Tax Authority [Member] Deferred Income Tax Liabilities [Line Items] Deferred Income Tax Liabilities [Line Items] [Line Items] for Deferred Income Tax Liabilities [Table] Accrued postretirement benefits Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Other benefit obligations Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Other Accounts receivable Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts State income tax loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards, State and Local U.S. Federal income tax loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards, Domestic U.S Federal foreign income tax credit carryforwards Deferred Tax Assets, Tax Credit Carryforwards, Foreign Non-U.S. income tax loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards, Foreign Non-U.S. capital loss carryforwards Deferred Tax Assets, Capital Loss Carryforwards Other Deferred Tax Assets, Tax Deferred Expense, Other Deferred tax assets Deferred Tax Assets, Gross Valuation allowance Deferred Tax Assets, Valuation Allowance Deferred tax assets, net Deferred Tax Assets, Net of Valuation Allowance Property, plant and equipment Deferred Tax Liabilities, Property, Plant and Equipment Prepaid pension cost Deferred Tax Liabilities, Prepaid Expenses Unrealized gain on available-for-sale securities Deferred Tax Liabilities, Unrealized Gains on Available-for-sale Securities Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on available-for-sale securities. Goodwill and other intangible assets Deferred Tax Liabilities, Goodwill and Intangible Assets Non-U.S. withholding tax Deferred Tax Liabilities, Undistributed Foreign Earnings Deferred tax liabilities Deferred Tax Liabilities, Gross Deferred Income Tax Liabilities, Net Deferred Income Tax Liabilities, Net Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Network affiliation agreements [Member] Contract-Based Intangible Assets [Member] Amortized Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Useful Life (in years) Gross Carrying Amount Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Net Carrying Amount Finite-Lived Intangible Assets, Net Schedule of Indefinite-Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] FCC licenses [Member] Operating and Broadcast Rights [Member] Licensure and Accreditation [Member] Licensure and Accreditation [Member] Licensure And Accreditation [Member] Indefinite-lived Intangible Assets [Line Items] Indefinite-lived Intangible Assets [Line Items] Net Carrying Amount Indefinite-Lived Intangible Assets (Excluding Goodwill) Business Segments Segment Reporting Disclosure [Text Block] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Common Class B [Member] Common Class B [Member] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Discontinued Operations, Disposed of by Means Other than Sale, Spinoff [Member] Discontinued Operations, Disposed of by Means Other than Sale, Spinoff [Member] Spin-off Stock Compensation Expense Period [Axis] Spin-off Stock Compensation Expense Period [Axis] Spin-off Stock Compensation Expense Period [Axis] Spin-off Stock Compensation Expense Period [Domain] Spin-off Stock Compensation Expense Period [Domain] [Domain] for Spin-off Stock Compensation Expense Period [Axis] Q3 2015 [Member] Q3 2015 [Member] Q3 2015 [Member] July 2015 through December 2018 [Member] July 2015 through December 2018 [Member] July 2015 through December 2018 [Member] Employee Stock Option [Member] Restricted Stock [Member] Restricted Stock [Member] Operating Activities [Axis] Operating Activities [Axis] Operating Activities [Domain] Operating Activities [Domain] Discontinued Operations [Member] Discontinued Operations [Member] Cable Spin-Off [Member] Cable Spin-Off [Member] Cable Spin-Off [Member] Sale Of Publishing Subsidiaries [Member] Sale Of Publishing Subsidiaries [Member] The sale of the Publishing Subsidiaries, which is comprised of WP Company LLC, Express Publications Company, LLC, El Tiempo Latino, LLC, Robinson Terminal Warehouse, LLC, Greater Washington Publishing, LLC and Post-Newsweek Media, LLC. Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Group Name [Domain] Disposal Group Name [Domain] WPLG [Member] WPLG [Member] WPLG [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Cable [Member] Cable [Member] Cable [Member] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Corporate office [Member] Corporate, Non-Segment [Member] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] GHC dividend received from Cable ONE Proceeds from Contributions from Affiliates Cable ONE, unsecured notes Debt Instrument, Face Amount Number of shares modified Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Number Of Shares The number of shares modified of an equity-based compensation plan. Number of employees affected by modification Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Number of Employees Affected Number of share awards with accelerated vesting Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number Number of shares forfeited due to modification Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Incremental stock compensation from modification Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost Curtailment gain Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment Net assets divested Disposal Group, Including Discontinued Operation, Assets Liabilities Net Net assets attributable to disposal group held for sale or disposed of, expected to be disposed within one year or the normal operating cycle, if longer. Net assets divested, net of cash Disposal Group, Including Discontinued Operations, Net Assets Net of Cash Net assets, net of cash, attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Net Cash Provided by Operating Activities Cash Provided by (Used in) Operating Activities, Discontinued Operations Net Cash Used in Investing Activities Cash Provided by (Used in) Investing Activities, Discontinued Operations Spin-off Costs Spin-off Costs Costs incurred as a direct cost to transact a spin-off. Pre-tax gain (loss) on sale and/or disposition Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax After-tax gain (loss) on sale and/or disposition Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Class A Common Stock [Member] Common Class A [Member] Class B Common Stock [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Capital in Excess of Par Value [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Retained Earnings [Member] AOCI Attributable to Parent [Member] AOCI Attributable to Parent [Member] Treasury Stock [Member] Treasury Stock [Member] Noncontrolling Interest [Member] Noncontrolling Interest [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] As of Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Net income (loss) for the year Acquisition of redeemable noncontrolling interest Equity Effect of Acquisition of Redeemable Noncontrolling Interest Equity Effect of Acquisition of Redeemable Noncontrolling Interest Contribution of noncontrolling interest to a joint venture Contribution of Noncontrolling Interest to a Joint Venture The value of the noncontrolling interest contributed to a joint venture. Net income attributable to noncontrolling interest Net income attributable to redeemable noncontrolling interests Net Income (Loss) Attributable to Redeemable Noncontrolling Interest Distribution to noncontrolling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Change in redemption value of redeemable noncontrolling interests Noncontrolling Interest, Change in Redemption Value Dividends paid on common stock Dividends, Common Stock Dividends paid on redeemable preferred stock Repurchase of Class B common stock Treasury Stock, Value, Acquired, Cost Method Issuance of Class B common stock, net of restricted stock award forfeitures Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Amortization of unearned stock compensation and stock option expense Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Other Comprehensive Income (Loss), Net of Tax Other Comprehensive Income (Loss), Net of Tax Reclassification From Accumulated Other Comprehensive Income To Retained Earnings Tax Cuts and Jobs Act 2017, Reclassification From Accumulated Other Comprehensive Income To Retained Earnings Amount of reclassification adjustments of stranded tax effects from accumulated other comprehensive income to retained earnings as a result of tax reform. Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax, Non-spinoff related Amount after tax and reclassification adjustments of other comprehensive income (loss) not related to a spin-off.. Reclassification of stranded tax effects as a result of tax reform Stock Issued During Period, Value, Conversion of Convertible Securities Spin-Off of Cable ONE Stockholders' Equity Note, Spinoff Transaction Taxes arising from employee stock plans Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Purchase of redeemable noncontrolling interest Equity effect of purchase of redeemable noncontrolling interest The equity effect of the purchase of redeemable noncontrolling interest Other Stockholders' Equity, Other Exchange of redeemable noncontrolling interest Exchange of Redeemable Noncontrolling Interest Effect of exchanging a redeemable noncontrolling interest for a mandatorily redeemable noncontrolling interest with entities under common control. As of Increase (Decrease) in Temporary Equity [Roll Forward] Increase (Decrease) in Temporary Equity [Roll Forward] As of Redeemable Noncontrolling Interest, Equity, Carrying Amount Acquisition of redeemable noncontrolling interest Acquisition of Redeemable Noncontrolling Interest The fair value of the creation of a redeemable noncontrolling interest due to the acquisition of less than 100% of an entity. Net income attributable to redeemable noncontrolling interests Temporary Equity, Net Income Change in redemption value of redeemable noncontrolling interests Temporary Equity, Change in Redemption Value Change in temporary equity during the period as a result of a change in the redemption value of redeemable noncontrolling interest. Other Temporary Equity, Other Changes Purchase of redeemable noncontrolling interest Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Exchange of redeemable noncontrolling interest Conversion of Redeemable Noncontrolling Interest The effect on the conversion of redeemable noncontrolling interest to mandatorily redeemable noncontrolling interest. As of Income Taxes [Table] Income Taxes [Table] -- None. No documentation exists for this element. -- Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] Capital loss carryforwards to 2013 tax year [Member] Capital Loss Carryforwards To 2013 Tax Year [Member] Capital loss carryforwards to the 2013 tax year [Member] Capital loss carryforward [Member] Capital Loss Carryforward [Member] State [Member] State and Local Jurisdiction [Member] U.S. Federal and State [Member] Domestic And State [Member] -- None. No documentation exists for this element. -- Australian Taxation Office [Member] Australian Taxation Office [Member] Carryforwards Period [Axis] CarryforwardsPeriod [Axis] -- None. No documentation exists for this element. -- Carryforward Period [Domain] Carryforward Period [Domain] Carryforward Period Domain Through 2022 [Member] Loss Carryforwards Expirations Range One [Member] -- None. No documentation exists for this element. -- After 2022 [Member] Loss Carryforwards Expirations Range Two [Member] -- None. No documentation exists for this element. -- Expire in 2024 [Member] Foreign Tax Credit Expiration Range 1 [Member] Foreign Tax Credit Expiration Range 1 [Member] Expire in 2025 [Member] Foreign Tax Credit Expiration Range 2 [Member] Foreign Tax Credit Expiration Range 2 [Member] Expire in 2026 [Member] Foreign Tax Credit Expiration Range 3 [Member] Foreign Tax Credit Expiration Range 3 [Member] Expire in 2027 [Member] Foreign Tax Credit Expiration Range 4 [Member] Foreign Tax Credit Expiration Range 4 [Member] Adjustment [Member] Scenario, Adjustment [Member] Forecast [Member] Scenario, Forecast [Member] Valuation Allowance by Deferred Tax Asset [Axis] Valuation Allowance by Deferred Tax Asset [Axis] Deferred Tax Asset [Domain] Deferred Tax Asset [Domain] Other [Member] Other [Member] Other [Member] Tax Credit Carryforwards, Foreign [Member] Tax Credit Carryforwards, Foreign [Member] Tax Credit Carryforwards, Foreign [Member] Internal Revenue Service (IRS) [Member] Internal Revenue Service (IRS) [Member] Tax Act [Axis] Tax Act [Axis] Tax Act [Axis] Tax Act [Domain] Tax Act [Domain] [Domain] for Tax Act [Axis] Reduction In Federal Tax Rate [Member] Reduction In Federal Tax Rate [Member] Reduction In Federal Tax Rate [Member] Change in Tax on non-US Subsidiary Earnings [Member] Change in Tax On Non-US Subsidiary Earnings [Member] Change in Non-US Subsidiary Earnings [Member] Recognition Period [Axis] Recognition Period [Axis] Recognition Period [Axis] Recognition Period [Domain] Recognition Period [Domain] [Domain] for Recognition Period [Axis] 2018 [Member] Recognition Period 1 [Member] Recognition Period 1 [Member] After 2018 [Member] Recognition Period 2 [Member] Recognition Period 2 [Member] Income Taxes [Line Items] Income Taxes [Line Items] Income Taxes [Line Items] Federal statutory income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Income Tax Expense (Benefit), Adjustment of Deferred Tax (Asset) Liability Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability Write-off of deferred taxes related to intercompany loans Income Tax Reconciliation Deferred Tax Assets Write-off Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to a deferred tax asset or liability write-off. Deferred income tax expense (benefit) Deferred Income Tax Expense (Benefit) Tax expenses with respect to losses from discontinued operations Discontinued Operation, Tax Effect of Discontinued Operation Income tax loss carryforwards to expire Income Tax Loss Carryforwards Subject to Expiration Income tax loss carryforwards subject to expiration. Deferred state income tax asset Income tax loss carryforwards obtained as a result of prior stock acqusitions Tax Loss Carryforward Prior Stock Acquisition Utilized Income tax loss carryforwards obtained as a result of prior stock acqusitions to be fully utilized. Deferred tax assets with respect to U.S. Federal income tax loss carryforwards Foreign tax credit carryforwards Foreign Tax Credit Carryforwards Foreign tax credits available to be credited against future U.S. Federal income tax liabilities. Valuation allowance on deferred tax asset related to foreign tax credit carryforwards Deferred Tax Assets, Valuation Allowance, Tax Credit Carryforwards, Foreign Valuation allowance of deferred tax asset attributable to foreign tax credit carryforward. Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount Amount of excess tax benefit booked as a discrete item related to the vesting of stock-based compensation under the adoption of ASU 2016-09. Deferred tax assets with respect to U.S. Federal foreign tax credit carryforwards Tax loss carryforwards as a result of operating losses and prior stock acquisitions Operating Losses And Prior Stock Acqusitions Carryforward Tax loss carryforwards as a result of operating losses and prior stock acquisitions Deferred tax assets with respect to non U.S. income tax loss carryforwards Valuation allowance against the deferred tax assets recorded for the tax losses carryforward Deferred Tax Asset Operating Losses And Prior Stock Acquisitions Carryforward Valuation Allowance Valuation allowance against the deferred tax assets recorded for the tax losses carryforward. Tax loss carryforwards from operating losses and prior stock acquisitions that can be carried forward indefinitely Operating Losses And Prior Stock Acqusitions Carryforward Indefinitely Tax loss carryforwards from operating losses and prior stock acquisitions that can be carried forward indefinitely. Tax loss carryforwards subject to expiration Operating Losses And Prior Stock Acqusitions Carryforward Subject To Expiration Tax loss carryforward resulting from operating losses and prior stock acquisitions subject to expiration. Carryforward amount Tax Credit Carryforward, Amount Non-U.S.deferred tax asset related to capital loss carryforwards Valuation Allowance, Amount Valuation allowance related to operating loss carryforwards Operating Loss Carryforwards, Valuation Allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Deferred income tax liabilities related to undistributed earnings of investments in non-U.S. subsidiaries Excess of book value over tax basis of investment Excess Of Book Value Over Tax Basis Of Investment Excess of book value over tax basis of investment in non-U.S. subsidiaries. Valuation allowance released Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Refund from Settlement with Taxing Authority Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority Decrease in Unrecognized Tax Benefits is Reasonably Possible Decrease in Unrecognized Tax Benefits is Reasonably Possible Unrecognized tax benefit that would impact the effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Federal tax impact of unrecognized tax benefits that would impact the effective tax rate Federal Tax Impact Of Unrecognized Tax Benefits that Would Impact Effective Tax Rate The federal tax impact of the total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Interest accrued related to unrecognized tax benefits Unrecognized Tax Benefits, Interest on Income Taxes Accrued Penalties accrued related to unrecognized tax benefits Unrecognized Tax Benefits, Income Tax Penalties Accrued Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Before Spin-off of Cable ONE [Member] Before Spin-off of Cable ONE [Member] Before Spin-off of Cable ONE [Member] After Spin-Off of Cable ONE [Member] After Spin-Off of Cable ONE [Member] After Spin-Off of Cable ONE [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Beginning, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Exercised, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Expired or forfeited, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period End, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning, Average Option Price (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted, Average Option Price (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised, Average Option Price (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Expired or forfeited, Average Option Price (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price End, Average Option Price (in dollars per share) Schedule of Income From Continuing Operations Before Income Taxes, Domestic and Foreign Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Schedule of Provision for Income Taxes on Income From Continuing Operations Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Income Tax Loss Carryforwards Summary of Operating Loss Carryforwards [Table Text Block] Schedule of Changes in Deferred Tax Valuation Allowance Summary of Valuation Allowance [Table Text Block] Schedule of Unrecognized Tax Benefits Roll Forward Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Income (Loss) from Continuing Operations before Income Taxes [Abstract] Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest [Abstract] U.S. Income (Loss) from Continuing Operations before Income Taxes, Domestic Non-U.S. Income (Loss) from Continuing Operations before Income Taxes, Foreign Disposal Groups, Including Discontinued Operations, Cash Flows [Table Text Block] Disposal Groups, Including Discontinued Operations, Cash Flows [Table Text Block] Tabular disclosure of cash flow information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component. Summarized Income (Loss) from Discontinued Operations, Net Of Tax Disposal Groups, Including Discontinued Operations [Table Text Block] Temporary Equity [Abstract] Redeemable Preferred Stock, par value per share Temporary Equity, Par or Stated Value Per Share Redeemable Preferred Stock, liquidation value per share Temporary Equity, Liquidation Preference Per Share Redeemable preferred shares outstanding Temporary Equity, Shares Outstanding Redeemable Preferred Stock, redemption value per share Temporary Equity, Redemption Price Per Share Redeemable preferred stock redemption amount Payments for Repurchase of Redeemable Preferred Stock Dividends payable per share Dividends Payable, Amount Per Share Number of times dividends payable in a year per share Preferred Stock, Number of Payments Per Year The number of payments preferred stock holders receive from dividends in a year. Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Equity Components [Axis] Foreign Currency Translation Adjustments [Member] Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Unrealized Gains (Losses) on Available- for- Sale Securities [Member] Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Pension and Other Postretirement Plans [Member] Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Net Actuarial Loss [Member] Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Net Prior Service Cost [Member] Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] Curtailment (Gains) Losses Included in Net Income [Member] AccumulatedDefinedBenefitPlansAdjustmentCurtailmentGainsIncludedInNetIncome [Member] Accumulated other comprehensive (income) loss related to the curtailment gains included in net income component of defined benefit plans attributable to the parent. Cash Flow Hedge [Member] Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Other (expense) income, net Interest expense Reclassifications, before tax Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Provision for income taxes Reclassification from AOCI, Current Period, Tax Reclassifications, net of tax Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Income from continuing operations before income taxes Income Net of Tax Other Postretirement Benefits Plan [Member] Benefit obligation at end of year, 1% Increase Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation Benefit obligation at end of year, 1% Decrease Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation Service cost plus interest cost, 1% Increase Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components Service cost plus interest cost, 1% Decrease Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components Accounts Receivable Accounts Payable And Accrued Liabilities [Abstract] -- None. No documentation exists for this element. -- Accounts Receivable Accounts Payable And Accrued Liabilities Accounts Receivable Accounts Payable And Accrued Liabilities [Text Block] The entire disclosure of Accounts Receivable Accounts Payable And Accrued Liabilities Schedule of Quantifying Prior Year Misstatement Corrected in Current Year Financial Statements [Table] Schedule of Quantifying Prior Year Misstatement Corrected in Current Year Financial Statements [Table] Periods from Q3 2016 to Q3 2017 [Member] Periods from Q3 2016 to Q3 2017 [Member] Periods from Q3 2016 to Q3 2017 [Member] [Member] Quantifying Misstatement in Current Year Financial Statements [Line Items] Quantifying Misstatement in Current Year Financial Statements [Line Items] Prior Period Reclassification Adjustment Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Noncurrent asset Assets for Plan Benefits, Defined Benefit Plan Current liability Liability, Defined Benefit Plan, Current Noncurrent liability Liability, Defined Benefit Plan, Noncurrent Recognized asset (liability) Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Valuation and Qualifying Accounts Disclosure [Table] Valuation and Qualifying Accounts Disclosure [Table] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves [Domain] Valuation Allowances and Reserves [Domain] Allowance for doubtful accounts[Member] Allowance for Doubtful Accounts [Member] Valuation and Qualifying Accounts Disclosure [Line Items] Valuation and Qualifying Accounts Disclosure [Line Items] Movement in Valuation Allowances and Reserves [Roll Forward] Movement in Valuation Allowances and Reserves [Roll Forward] Balance at Begining of Period Valuation Allowances and Reserves, Balance Additions - Charged to Costs and Expenses Valuation Allowances and Reserves, Additions for Charges to Cost and Expense Deductions Valuation Allowances and Reserves, Deductions Balance at End of Period Accounts Receivable, Net [Abstract] Accounts Receivable, Net [Abstract] Trade accounts receivable, less doubtful accounts and allowances Accounts Receivable, Net, Current Other receivables Other Receivables Accounts receivable, net Accounts and Other Receivables, Net, Current Allowance for Doubtful Accounts Receivable Allowance for Doubtful Accounts Receivable Accounts Payable, Current [Abstract] Accounts Payable, Current [Abstract] Accounts payable and accrued liabilities Accounts Payable and Other Accrued Liabilities, Current Accrued compensation and related benefits Employee-related Liabilities, Current Total accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities, Current Total cost Available-for-sale Equity Securities, Amortized Cost Basis Gross unrealized gains Available-for-sale Equity Securities, Accumulated Gross Unrealized Gain, before Tax Gross unrealized losses Available-for-sale Equity Securities, Accumulated Gross Unrealized Loss, before Tax Total Fair Value Available-for-sale Securities, Equity Securities Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Benefit obligation at begining of year Defined Benefit Plan, Benefit Obligation Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Amendments Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Actuarial (gain) loss Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Acquisitions Defined Benefit Plan, Benefit Obligation, Business Combination Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Curtailment Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment Special termination benefits Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits Benefits paid, net of Medicare subsidy Defined Benefit Plan Benefits Paid Net The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets. This amount is net of Medicary subsidies. Settlement Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement Benefit obligation at end of year Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer Benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Benefits paid, net of Medicare subsidy Settlement Defined Benefit Plan, Plan Assets, Payment for Settlement Funded status Defined Benefit Plan, Funded (Unfunded) Status of Plan Expected life (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Interest rate, minimum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Interest rate, maximum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum Volatility, minimum (percentage) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Volatility (percentage) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Volatility, maximum (percentage) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Early Retirment Program Expense [Axis] Early Retirment Program Expense [Axis] -- None. No documentation exists for this element. -- Early Retirement Program Expense [Domain] Early Retirement Program Expense [Domain] -- None. No documentation exists for this element. -- Special Incentive Program [Member] Special Incentive Program [Member] Special Incentive Program [Member] Separation Incentive Program [Member] Separation Incentive Program [Member] Separation Incentive Program [Member] Voluntary Retirement Incentive Program [Member] Voluntary Retirement Incentive Program [Member] -- None. No documentation exists for this element. -- Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Defined Benefit Plan Assets Total [Member] Defined Benefit Plan Assets Total [Member] -- None. No documentation exists for this element. -- Concentration Risk by Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Concentration In Single Entity, Type Of Industry, Foreign Country Or Individual Fund [Member] Concentration In Single Entity, Type Of Industry, Foreign Country Or Individual Fund [Member] Concentration In Single Entity, Type Of Industry, Foreign Country Or Individual Fund [Member] Geographic Concentration [Member] Geographic Concentration Risk [Member] Single Equity Concentration [Member] Single Equity Concentration [Member] Information about an entity's defined benefit plan's significant investment concentrations in either a single entity, type of industry, foreign country and/or individual fund. Defined Benefit Plan by Plan Asset Categories [Axis] Defined Benefit Plan, Asset Categories [Axis] Plan Asset Categories [Domain] Plan Asset Categories [Domain] Foreign Investments [Member] Foreign Investments [Member] Information about the entity's defined pension plan foreign investments. Fixed income securities [Member] Fixed Income Securities [Member] Equity securities [Member] Equity Securities [Member] Equity funds [Member] Equity Funds [Member] Schedule Of Marketable Securities Equity Securities Investee Name [Axis] Schedule Of Marketable Securities Equity Securities Investee Name [Axis] -- None. No documentation exists for this element. -- Marketable Securities Equity Securities Investee, Name [Domain] Marketable Securities Equity Securities Investee, Name [Domain] -- None. No documentation exists for this element. -- Berkshire Hathaway Common Stock [Member] Berkshire Hathaway Common Stock [Member] Berkshire Hathaway Common Stock [Member] Corporate Office [Member] Corporate Office [Member] Corporate Office [Member] Defined Benefit Plan Health Care Cost Trend Groups [Axis] Defined Benefit Plan Health Care Cost Trend Groups [Axis] Defined Benefit Plan Health Care Cost Trend Groups [Axis] Defined Benefit Plan Health Care Cost Trend Groups [Domain] Defined Benefit Plan Health Care Cost Trend Groups [Domain] Defined Benefit Plan Health Care Cost Trend Groups [Domain] Pre-Age 65 [Member] Pre-Age 65 [Member] Pre-Age 65 [Member] Post-Age 65 [Member] Post Age 65 [Member] Post Age 65 [Member] Multiemployer Plan Type [Axis] Multiemployer Plan Type [Axis] Multiemployer Plans Type [Domain] Multiemployer Plans Type [Domain] Multiemployer Pension Plans [Member] Multiemployer Plans, Pension [Member] Retirement Benefits Disclosure [Line Items] Retirement Benefits Disclosure [Line Items] Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Early retirement and special separation benefit program expense Defined Benefit Plan, Cost of Providing Special and Contractual Termination Benefits Settlement Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement Accumulated benefit obligation Defined Benefit Plan, Accumulated Benefit Obligation Company contributions Estimated employer contributions in next fiscal year Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year Net Periodic Cost (Benefit) for the Year Net Periodic Benefit For Defined Benefit Pension Plans Excluding Early Retirement Program, Special Separation Benefit Expense, Curtailment And Settlement The net periodic benefit or expense for defined benefit pension plans excluding the early retirement program and special separation benefit expense, curtailment, settlement and other programs separately disclosed in the financial statements. Curtailment Percent of Plan Assets Managed Internally by Company Percent of Plan Assets Managed Internally by Company The percentage of plan assets managed internally by the Company. Percent Of Plan Assets Managed By Investment Companies Percent Of Plan Assets Managed By Investment Companies The percentage of plan assets managed by investment companies. Number of investment companies actively managing plan assets Number Of Investment Companies Managing Plan Assets The number of investment companies actively managing plan assets. Defined benefit plan, target allocation maximum percentage of assets, singular equity security, without prior approval by plan administrator Defined Benefit Plan Target Allocation Percentage Of Assets Singular Equity Security Limit Without Approval Of Plan Administrator Target allocation maximum percentage of investment in a single equity security to total plan assets without prior approval of plan administrator. Defined benefit plan, target allocation percentage of assets Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Minimum percentage of plan assets considered as significant concentrations in pension plans Concentration Risk, Percentage Number of investments the company's pension plan held which individually exceed 10% of total plan assets Number Of Investments Companys Pension Plan Held Which Individually Exceed 10 Percent Of Total Plan Assets Number Of Investments The Companys Pension Plan Held Which Individually Exceed 10 Percent Of Total Plan Assets Number of foreign countries for which the companys pension plan holds investments that exceed 10% of total plan assets Number Of Foreign Countries For Which Companys Pension Plan Holds Investments That Exceed 10 Percent Of Total Plan Assets Number of foreign countries for which the companys pension plan holds investments that exceed 10% of total plan assets Value of investments Investments Percentage of total plan assets Defined Benefit Plan, Actual Plan Asset Allocations Discount rate to determine benefit obligation Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Assumed health care cost trend rate Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year Direction of change for assumed health care cost trend rate Defined Benefit Plan, Assumed Health Care Cost Trend Rate, Description Ultimate health care cost trend rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Year that rate reaches ultimate trend rate Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate Discount rate to determine periodic cost Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Number of multiemployer plans contributed to Number Of Multiemployer Plans Contributed To Number of multiemployer pension plans to which the Company contributed. Contributions to multiemployer pension plans Multiemployer Plan, Contributions by Employer Expense associated with the retirement benefits provided under incentive savings plans Defined Contribution Plan, Cost Accounting Changes and Error Corrections [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Domain] Adjustments for Change in Accounting Principle [Domain] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Schedule of Prospective Adoption of New Accounting Pronouncements [Table Text Block] Schedule of Prospective Adoption of New Accounting Pronouncements [Table Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Income Taxes Income Tax Disclosure [Text Block] Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] U.S. Federal taxes at statutory rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount State and local taxes, net of U.S. Federal tax Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Valuation allowance against tax benefits Deferred taxes on future distributions of unremitted non-U.S. subsidiary earnings Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount Stock based compensation Goodwill impairments and dispositions Effective Income Tax Rate Reconciliation, Impairment Losses and Disposition of Business Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible impairment loss and the disposition of a business not qualifying as a discontinued operation. U.S. Federal Manufacturing Deducation tax benefits Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Amount Deferred tax impact of U.S. Federal tax rate reduction to 21%, net of state tax impact Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Deferred tax benefit on unremitted non-U.S. subsidiary earnings Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Total provision for income tax Changes in Carrying Amount of Goodwill Schedule of Goodwill [Table Text Block] Other Intangible Assets Schedule of Finite and Indefinite Lived Intangible Assets [Table Text Block] Schedule of Finite and Indefinite Lived Intangible Assets [Table Text Block] Operating Segments [Member] Operating Segments [Member] Intersegment Elimination [Member] Intersegment Eliminations [Member] Healthcare [Member] Healthcare [Member] Healthcare [Member] Other Segments [Member] Other Segments [Member] Subsegments Consolidation Items [Axis] Subsegments Consolidation Items [Axis] Subsegments Consolidation Items [Domain] Subsegments Consolidation Items [Domain] Reportable Subsegments [Member] Reportable Subsegments [Member] Intersubsegment Eliminations [Member] Intersubsegment Eliminations [Member] Professional (U.S.) [Member] Professional (U.S.) [Member] Professional (U.S.) [Member] Operating Revenues Income (loss) from operations Interest expense, net Interest Income (Expense), Net Non-operating pension and postretirement benefit income, net Income (Loss) from Continuing Operations Before Income Taxes Amortization of intangible assets and impairment of goodwill and other long-lived assets Amortization Of Intangible Assets And Impairment Of Goodwill And Other Long-Lived Assets Amortization of intangible assets and impairment of goodwill and other long-lived assets during the period. Pension Expense - Service Cost Pension Expense - Service Cost Defined Benefit Plan, Service Cost, for Continuing Operations Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan, for continuing operations. Impairment of goodwill and other long-lived assets Impairment Of Goodwill And Other Long-Lived Assets Total loss recognized during the period from the impairment of goodwill, intangible assets and other long-lived assets. Capital expenditures Payments To Acquire Property, Plant, And Equipment From Continuing Operations The cash flow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale of continuing operations; includes cash outflows to pay for construction of self-constructed assets. Identifiable Assets Identifiable Assets Identifiable assets by segment are those assets used in the Company's operations in each business segment. Investments in Marketable equity securities Investments in Affiliates Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Prepaid Pension Cost Total Assets Assets Defined Benefit Plans [Member] Defined Benefit Plans [Member] Defined benefit plans consisting of various pension plans and a Supplemental Executive Retirement Plan (SERP). Defined Benefit Plans Disclosures Defined Benefit Plans Assumption [Axis] Defined Benefit Plans Disclosures Defined Benefit Plans Assumption [Axis] Reflects the description and required disclosures pertaining to the entity's defined benefits pension, by plan or groupings of similar plans. Defined Benefit Plans Disclosures Defined Benefit Plans Assumption [Domain] Defined Benefit Plans Disclosures Defined Benefit Plans Assumption [Domain] Defined Benefit Plans Disclosures Defined Benefit Plans Assumption [Domain] Periodic Cost [Member] Periodic Cost [Member] Periodic cost assumptions. Benefit Obligation [Member] Benefit Obligation [Member] Benefit obligation assumptions. Schedule of Obligation, Asset and Funding Information Schedule of Net Funded Status [Table Text Block] Schedule of Amounts Recognized in Balance Sheet Schedule of Amounts Recognized in Balance Sheet [Table Text Block] Schedule of Assumptions Used Schedule of Assumptions Used [Table Text Block] Schedule of Estimated Benefit Payments Schedule of Expected Benefit Payments [Table Text Block] Schedule of Net (Benefit) Costs Schedule of Net Benefit Costs [Table Text Block] Schedule of Amounts Recognized in Accumulated Other Comprehensive Income (Loss) Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Schedule of Expected Net Periodic Cost to be Recognized in Accumulated Other Comprehensive Income (Loss) Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block] Allocation of the Assets of the Company's Pension Plans Schedule of Allocation of Plan Assets [Table Text Block] Fair Value, Assets Measured on Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block] Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Impairment of intangible assets Impairment of Intangible Assets, Finite-lived Number of businesses that recorded impairment of intangible and other long-lived assets Number of Businesses Recorded Impairment of Intangible And Other Long-Lived Assets Number of businesses that recorded impairment of intangible and other long-lived assets. Impairment of intangible and other long-lived assets Impairment Of Intangible And Other Long-Lived Assets The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of intangible and other long-lived assets. Amortization of Intangible Assets Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Estimated amortization of intangible assets, 2018 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Estimated amortization of intangible assets, 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Two Estimated amortization of intangible assets, 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Three Estimated amortization of intangible assets, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Four Estimated amortization of intangible assets, 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Five Estimated amortization of intangible assets, after 2022 Finite-Lived Intangible Assets, Amortization Expense, after Year Five Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Schedule of Non-Operating Income (Expense) [Table] Schedule of Non-Operating Income (Expense) [Table] Schedule of Non-Operating Income (Expense) [Table] Classified Ventures LLC [Member] Classified Ventures Llc [Member] Classified Ventures LLC [Member] Schedule of Non-Operating (Expense) Income [Line Items] Schedule of Non-Operating Income (Expense) [Line Items] [Line Items] for Schedule of Non-Operating Income (Expense) [Table] Foreign currency gain (losses), net Foreign Currency Transaction Gain (Loss), before Tax Net (loss) gain on sales of businesses Gain (Loss) on Disposition of Business Net losses on sales or write-downs of cost method investments Cost-method Investments, Realized Gain (Loss) Gain on sale of property, plant and equipment Gain (Loss) on Disposition of Property Plant Equipment Gain on formation of a joint venture Deconsolidation, Gain (Loss), Amount Gain on sale of Classified Ventures Equity Method Investment, Realized Gain (Loss) on Disposal Net losses on sales or write-down of marketable equity securities Marketable Securities, Realized Gain (Loss) Other, net Other Nonoperating Gains (Losses) Other Comprehensive Income (Loss) [Table] Other Comprehensive Income (Loss) [Table] Other Comprehensive Income (Loss) [Table] Foreign Currency Translation Adjustment [Member] Curtailments and settlements Included in Net Income [Member] Curtailment And Settlement Included in Distribution [Member] AccumulatedDefinedBenefitPlansAdjustmentCurtailmentAndSettlementIncludedInDistribution [Member] Accumulated other comprehensive (income) loss related to the curtailment and settlement included in distribution to affiliate component of defined benefit plans attributable to the parent. Other Comprehensive Income (Loss) [Line Items] Other Comprehensive Income (Loss) [Line Items] [Line Items] for Other Comprehensive Income (Loss) [Table] Other Comprehensive Income (Loss), before Reclassifications, before Tax Other Comprehensive Income (Loss), before Reclassifications, before Tax Other Comprehensive Income (Loss) before Reclassifications, Tax Other Comprehensive Income (Loss) before Reclassifications, Tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Reclassification from AOCI, Current Period, Tax Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Other Comprehensive Income (Loss), Before Tax Other Comprehensive Income (Loss), before Tax Other Comprehensive Income (Loss), Income Tax Other Comprehensive Income (Loss), Tax Other Comprehensive Income (Loss), Net of Tax Pro Forma Operating revenues Business Acquisition, Pro Forma Revenue Pro Forma Net income (loss) Business Acquisition, Pro Forma Net Income (Loss) Statement of Financial Position [Abstract] Redeemable Preferred Stock, shares authorized Temporary Equity, Shares Authorized Redeemable Preferred Stock, shares issued Temporary Equity, Shares Issued Redeemable Preferred Stock, shares outstanding Preferred Stock, par value per share Preferred Stock, Par or Stated Value Per Share Preferred Stock, shares authorized Preferred Stock, Shares Authorized Preferred Stock, shares issued Preferred Stock, Shares Issued Common Stock, par value per share Common Stock, Par or Stated Value Per Share Common Stock, shares authorized Common Stock, Shares Authorized Common Stock, shares issued Common Stock, Shares, Issued Common Stock, shares outstanding Common Stock, Shares, Outstanding Treasury Stock Treasury Stock, Shares Cash held for sale Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Accelerated depreciation Restructuring and Related Cost, Accelerated Depreciation Lease obligation losses Restructuring Reserve Lease Obligation Losses Amount of lease obligations charged against earnings associated with exit from or disposal of business activities or restructuring plan. Severance Severance Costs Other Other Restructuring Costs Total restructuring costs Future minimum lease payments for 2018 Operating Leases, Future Minimum Payments Due, Next Twelve Months Future minimum lease payments for 2019 Operating Leases, Future Minimum Payments, Due in Two Years Future minimum lease payments for 2020 Operating Leases, Future Minimum Payments, Due in Three Years Future minimum lease payments for 2021 Operating Leases, Future Minimum Payments, Due in Four Years Future minimum lease payments for 2022 Operating Leases, Future Minimum Payments, Due in Five Years Future minimum lease payments after 2022 Operating Leases, Future Minimum Payments, Due Thereafter Operating leases, future minimum payments due, total Operating Leases, Future Minimum Payments Due Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract] Cash and cash equivalents Accounts receivable, net Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net Other current assets Disposal Group, Including Discontinued Operation, Prepaid and Other Assets, Current Total current assets Disposal Group, Including Discontinued Operation, Current Assets, Current Amount classified as current assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Property, plant and equipment, net Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Current Goodwill, net Disposal Group, Including Discontinued Operation, Goodwill, Current Indefinite-lived intangible assets, net Disposal Group, Including Discontinued Operation, Indefinite-lived Intangible Assets Excluding Goodwill For the disposal group, including a component of the entity (discontinued operation), amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. Amortized intangible assets, net Disposal Group, Including Discontinued Operation, Amortizable Intangibles, Current Amount classified as amortizable intangible assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Deferred charges and other assets Disposal Group, Including Discontinued Operation, Other Assets, Current Total Assets Disposal Group, Including Discontinued Operation, Assets, Current Accounts payable and accrued liabilities Disposal Group, Including Discontinued Operation, Accounts Payable and Accrued Liabilities, Current Income taxes payable Disposal Group, Including Discontinued Operation, Accrued Income Tax Payable, Current Deferred revenue Disposal Group, Including Discontinued Operation, Deferred Revenue, Current Short-term borrowings Disposal Group, Including Discontinued Operations, Current Maturities of Long-Term Debt Amount classified as current maturities of long-term debt attributable to disposal group held for sale of disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Total current liabilities Disposal Group, Including Discontinued Operations, Current Liabilities, Current Amount classified as current liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Accrued compensation and related benefits Disposal Group, Including Discontinued Operations, Accrued Compensation and Related Benefits Amount classified as accrued compensation and other related benefits attributable to disposal group held for sale of disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Other liabilities Disposal Group, Including Discontinued Operation, Other Liabilities, Current Deferred income taxes Disposal Group, Including Discontinued Operation, Deferred Tax Liabilities, Current Long-term debt Disposal Group, Including Discontinued Operations, Long-term Debt Amount of long-term debt attributable to disposal group held for sale of disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Total Liabilities Disposal Group, Including Discontinued Operation, Liabilities, Current Net assets divested in the Spin-Off Discount rate (percent) Expected return on plan assets (percent) Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Rate of compensation increase (percent) Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Schedule of Future Minimum Rental Payments for Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Schedule of assets acquired and liabilities assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Acqusition Pro Forma Financial Information Business Acquisition, Pro Forma Information [Table Text Block] Information related to a Disposal Group Schedule Of Disposal Groups Excluding Discontinued Operations Income Statement Balance Sheet And Additional Disclosures [Table Text Block] Tabular disclosure of information related to a disposal group. Excludes a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component. Other Income and Expenses (Narrative) [Abstract] Other Income and Expenses (Narrative) [Abstract] Vocational School Company [Member] Vocational School Company [Member] Vocational School Company [Member] Residential Healthcare Group Inc [Member] Residential Healthcare Group Inc [Member] Residential Healthcare Group Inc [Member] Celtic Healthcare Inc [Member] Celtic Healthcare Inc [Member] -- None. No documentation exists for this element. -- Berkshire Hathaway Inc [Member] Berkshire Hathaway Inc [Member] Berkshire Hathaway Inc.[Member] Colloquy [Member] Colloquy [Member] Colloquy [Member] Common Class A [Member] Residential And Michigan Hospital Joint Venture [Member] Residential And Michigan Hospital Joint Venture [Member] Residential and a Michigan hospital joint venture [Member] Berkshire Exchange Transaction [Member] Berkshire Exchange Transaction [Member] Berkshire Exchange Transaction [Member] Write-downs of cost method investment Cost-method Investments, Other than Temporary Impairment Ownership percentage of investment in affiliate Equity Method Investment, Ownership Percentage Gain (loss) on sale of business Number Of Businesses Disposed Number Of Businesses Disposed The number of businesses disposed of by the entity during the period. Favorable out of period adjustment Proceeds from sale of equity method investment, including amount held in escrow Proceeds From Sale Of Equity Method Investments Including Escrow The total cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence, including amount held in escrow and to be received at a later date. Amount of cash proceeds held in escrow Amount Of Equity Method Investment Sale Cash Proceeds Held In Escrow Relating to the sale of an equity method investment, the amount of the remaining cash proceeds held by a third party on behalf of the other two parties until all remaining sale agreement obligations have been fulfilled. Proceeds from sale of equity method investment Proceeds from Sale of Equity Method Investments Gain on sale of an equity affiliate Number of shares exchanged Number of Shares Exchanged Number of shares exchanged in a transaction. Gain on share exchange Gain on Share Exchange This item represents the total realized gain included in earnings for the period as a result of exchanging marketable securities. Proceeds from sale of headquarters building Proceeds from Sale of Property, Plant, and Equipment Gain on sale of headquarters building Gain (Loss) On Sale of Building Amount of gain (loss) on sale of disposal of building. Capital Stock, Stock Awards And Stock Options Capital Stock, Stock Awards And Stock Options [Text Block] -- None. No documentation exists for this element. -- Cash overdrafts Bank Overdrafts Components of Debt Schedule of Long-term Debt Instruments [Table Text Block] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Beginning of year, unvested, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Awarded, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited, Number of Shares End of year, unvested, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Beginning of year, Average Grant-Date Fair Value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Awarded, Average Grant-Date Fair Value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Vested, Average Grant-Date Fair Value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeited, Average Grant-Date Fair Value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value End of year, Average Grant-Date Fair Value (in dollars per share) Schedule of Quarterly Results of Operations and Comprehensive Income Quarterly Financial Information [Table Text Block] Schedule Of Quarterly Impact From Certain Items Schedule Of Quarterly Impact From Certain Items [Table Text Block] Tabular disclosure Quarterly Impact From Certain Items. Kaplan University Transaction [Member] Kaplan University Transaction [Member] Kaplan University Transaction [Member] Group Dekko [Member] Group Dekko [Member] Group Dekko [Member] Mander Portman Woodward [Member] Mander Portman Woodward [Member] Mander Portman Woodward [Member] Osborne Books [Member] Osborne Books [Member] Osborne Books [Member] Electri-Cable Assemblies [Member] Electri-Cable Assemblies [Member] Electri-Cable Assemblies [Member] SmartPros [Member] SmartPros [Member] SmartPros [Member] VNA-TIP Healthcare [Member] VNA-TIP Healthcare [Member] VNA-TIP Healthcare [Member] Joyce/Dayton Corp [Member] Joyce/Dayton Corp [Member] Joyce/Dayton Corp [Member] Residential Hospice Illinois [Member] Residential Hospice Illinois [Member] Residential Hospice Illinois [Member] Residential Home Health Illinois [Member] Residential Home Health Illinois [Member] Residential Home Health Illinois [Member] Disposal Group, Not Discontinued Operation, Revenue Disposal Group, Not Discontinued Operation, Revenue Amount of revenue attributable to disposal group. Excludes discontinued operations. Cost of acquisition Business Combination, Consideration Transferred Pension and other post retirement benefits liabilities Number of businesses acquired Number of Businesses Acquired Percentage of interest acquired Business Acquisition, Percentage of Voting Interests Acquired Payments to Acquire Businesses, Net of Cash Acquired Payments to Acquire Businesses, Net of Cash Acquired Fair value of redeemable noncontrolling interest acquired Business Combination Acquisition Of Less than 100 Percent Redeemable Noncontrolling Interest Fair Value This element represents the fair value of the redeemable noncontrolling interest in the acquiree at the acquisition date. Acquisition-related costs Business Acquisition, Transaction Costs Goodwill expected to be deductible for income tax purposes Business Acquisition, Goodwill, Expected Tax Deductible Amount Measurement period adjustment Goodwill, Purchase Accounting Adjustments Revenues of acquired companies since acquisition date Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual Operating income of acquired companies since acquisition date Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual Impairment Of Long Lived Assets Impairment Of Long Lived Assets The aggregate amount of write-downs recognized during the period for long-lived assets. Percentage of joint venture sold Percentage Of Joint Venture Sold The percentage of a joint venture sold. Noncontrolling interest purchased Noncontrolling Interest Purchased Percent of noncontrolling interest purchased during the period. Redeemable Noncontrolling Interest, Equity, Common, Redemption Value Redeemable Noncontrolling Interest, Equity, Common, Redemption Value Noncontrolling interest exchanged Noncontrolling Interest Exchanged The percentage of redeemable noncontrolling interest exchanged. Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners Payments to acquire businesses per agreement Payments To Acquire Businesses Per Agreement The payments to be paid to acquire businesses per agreement. Number of television stations included in agreement to acquire Number Of Television Stations Included In Agreement To Acquire The number of television stations included in agreement to acquire. Number of business lines Number of Business Lines The number of business lines. Amount of Cash Exchanged Amount of Cash Exchanged Amount of cash paid in a transaction Number of Shares Received in Exchange Number of Shares Received in Exchange The number of shares received in an exchange transaction Fair value of available-for-sale equity securities exchanged Available For Sale Securities Equity Securities Exchanged Fair Value Fair value of of available-for-sale equity securities exchanged. Estimated fair value of business exchanged Estimated Fair Value of Business Exchanged Estimated fair value of business exchanged. Treasury stock increase Percentage of Celtic Revenue Percentage of Celtic Revenue The percentage of total Celtic revenue that is now part of the joint venture. Transition and Operations Support Agreement Initial Term Transition and Operations Support Agreement Initial Term Transition and Operations Support Agreement Initial Term Transition and Operations Support Agreement Buy-Out Option Eligible Year Transition and Operations Support Agreement Buy-Out Option Eligible Year Transition and Operations Support Agreement Buy-Out Option Eligible Year Disposal Groups, Including Discontinued Operations [Table] Disposal Group, Not Discontinued Operation, Operating Loss Disposal Group, Not Discontinued Operation, Operating Income (Loss) Amount of operating income (loss) attributable to disposal group. Excludes discontinued operations. Goodwill [Roll Forward] Goodwill [Roll Forward] Goodwill, beginning balance Goodwill, Gross Accumulated impairment losses, beginning balance Goodwill, Impaired, Accumulated Impairment Loss Goodwill, net, beginning balance Acquisitions Goodwill, Acquired During Period Impairment Dispositions Goodwill, Written off Related to Sale of Business Unit Foreign currency exchange rate changes Goodwill, Foreign Currency Translation Gain (Loss) Goodwill, ending balance Accumulated impairment losses, ending balance Goodwill, net, ending balance Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table] Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2012 Incentive Compensation Plan [Member] 2012 Incentive Compensation Plan [Member] 2012 Incentive Compensation Plan which authorizes the awarding of Class B common stock to key employees in the form of stock awards, stock options and other awards involving the actual transfer of shares. [Member] Kaplan Stock Option and Restricted Stock [Member] Kaplan Stock Option and Restricted Stock [Member] Kaplan Stock Option and Restricted Stock [Member] Exercise Price Range [Axis] Exercise Price Range [Axis] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain] Exercise Price Range of $244-$284 [Member] Price Range One [Member] Exercise Price Range of $244-284 Exercise Price $325 [Member] Price Range Two [Member] Exercise Price of $325 Exercise Price $719 [Member] Price Range Three [Member] Exercise Price of $719 Exercise Price Range of $805-$872 [Member] Price Range Four [Member] Exercise Price of $805-872 Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] Low Exercise Price Range Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit High Exercise Price Range Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit Options Outstanding, Shares Outstanding Options Outstanding, Weighted Average Remaining Contractual Life (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Options Outstanding, Weighted Average Exercise Price (in dollars per share) Options Exercisable, Shares Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Options Exercisable, Weighted Average Remaining Contractual Life (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Options Exercisable, Weighted Average Exercise Price (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization and Nature of Operations Nature of Operations [Text Block] Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Accounting Standards Update 2017-07 [Member] Accounting Standards Update 2017-07 [Member] Accounting Standards Update 2017-07 [Member] As Previously Reported [Member] Scenario, Previously Reported [Member] Adjustment [Member] Restatement Adjustment [Member] Operating expenses Selling, general and administrative expenses Income (Loss) from Operations Income before Income Taxes Land Land Buildings Buildings and Improvements, Gross Machinery, equipment and fixtures Machinery and Equipment, Gross Leasehold improvements Leasehold Improvements, Gross Construction in progress Construction in Progress, Gross Property, plant and equipment, gross Property, Plant and Equipment, Gross Less accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, plant and equipment, net Property, Plant and Equipment, Net Debt Debt Disclosure [Text Block] Schedule of Operating Leased Assets [Table] Schedule of Operating Leased Assets [Table] Operating Leased Assets [Line Items] Operating Leased Assets [Line Items] Future minimum sublease payments due Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals Rent expense for operating leases Operating Leases, Rent Expense Sublease rental income Operating Leases, Income Statement, Sublease Revenue Secondarily liable leases Secondarily Liable Leases Amount of lease obligations for which the Company is secondarily liable. Long-term programming purchase commitment Long-term Purchase Commitment, Amount Statement of Comprehensive Income [Abstract] Net Income (Loss) Other Comprehensive Income (Loss), Before Tax Other Comprehensive Income (Loss), before Tax [Abstract] Foreign currency translation adjustments: Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax, Portion Attributable to Parent [Abstract] Translation adjustments arising during the year Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss), before Reclassification and Tax Adjustment for sales of businesses with foreign operations Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax Total foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax Unrealized gains on available-for-sale securities: Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, [Abstract] Unrealized gains for the year Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Reclassification adjustment for realization of loss (gain) on sale of available-for-sale securities included in net income Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Total unrealized gains on available-for-sale securities Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax Pension and other postretirement plans: Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract] Actuarial gain (loss) Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Prior service cost Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax Amortization of net actuarial (gain) loss included in net income Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Amortization of net prior service cost included in net income Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax Curtailments and settlements included in net income Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), before Tax Curtailments and settlements included in distribution to Cable ONE Other Comprehensive Income (Loss), Finalization of Pension and Other Postretirement Benefit Plan Valuation, Spin-off, Before Tax Amount before tax of gain (loss) adjustment to other comprehensive income (loss) resulting from settlement or curtailment of defined benefit pension and other postretirement defined benefit plans due to a spin-off. Total pension and other postretirement plans Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Cash flow hedge gain (loss) Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax Other Comprehensive Income (Loss), Before Tax Income tax (expense) benefit related to items of other comprehensive income (loss) Comprehensive Income (Loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive income attributable to noncontrolling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Total Comprehensive Income (Loss) Attributable to Graham Holdings Company Schedule of Investments [Table] Schedule of Investments [Table] York University [Member] York University [Member] York University [Member] Markel Corporation [Member] MarkelCorporation [Member] Markel Corporation [Member] Intersection [Member] Intersection [Member] Intersection Holdings,LLC [Member] Classified Ventures' sale of apartments.com [Member] Classified Ventures' sale of apartments.com [Member] Classified Ventures' sale of apartments.com [Member] York Joint Venture [Member] York Joint Venture [Member] York Joint Venture [Member] HomeHero [Member] HomeHero [Member] HomeHero [Member] Schedule of Investments [Line Items] Schedule of Investments [Line Items] Commercial paper and money market investments Commercial Paper And Money Market Investments Unsecured short-term debt instrument issued by corporations which are highly liquid investments that are readily convertible to know amounts of cash and interest-bearing accounts that typically pay a higher interest rate and are FDIC insured. Number of shares held in investment Number Of Shares Held In Investment The number of shares held in an investment. Cash paid for new marketable equity securities Payments to Acquire Available-for-sale Securities, Equity Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds Marketable equity securities purchased Available For Sale Securities Equity Acquired Equity securities classified as available-for-sale securities acquired. Loss on sales of marketable equity securities Marketable Securities, Realized Loss, Excluding Other than Temporary Impairments This item represents the total realized loss included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Gain on sales of marketable equity securities Marketable Securities, Realized Gain (Loss), Excluding Other than Temporary Impairments Equity Method Investment, Ownership Percentage Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions Revenue from Related Parties Revenue from Related Parties Other Commitment Other Commitment Loan Receivable, Payment Term Loan Receivable, Payment Terms Description of the payment terms of the debt instrument (for example whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment. Related Party Transaction, Rate Related Party Transaction, Rate Advances to Affiliate Advances to Affiliate Equity Method Investment, Other than Temporary Impairment Equity Method Investment, Other than Temporary Impairment Loan receivable, Fixed Rate of Interest Loan Receivable Fixed Interest Rate Loan Receivable Fixed Interest Rate Accounts Receivable, Related Parties, Noncurrent Notes Receivable, Related Parties, Noncurrent Pre-tax gain on equity method investment Pre-tax gain (loss) on sale of equity method investment Cash distribution from equity method investment Equity Method Investment, Cash Distributions Amount of gross cash distributions received from an equity method investment. Face amount of debt issued Debt Instrument, Term Debt Instrument, Term Exercise Price Above Fair Market Value Of Common Stock [Member] Exercise Price Above Fair Market Value Of Common Stock [Member] -- None. No documentation exists for this element. -- Kaplan Restricted Stock [Member] Kaplan Restricted Stock [Member] -- None. No documentation exists for this element. -- Kaplan Stock Option [Member] Kaplan Stock Option [Member] -- None. No documentation exists for this element. -- 2003 Employee Stock Option Plan [Member] 2003 Employee Stock Option Plan [Member] 2003 Employee Stock Option Plan reserves shares of the Company's Class B common stock for options to be granted under the plan. [Member] Dividends [Axis] Dividends [Axis] Dividends [Domain] Dividends [Domain] Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits, by Title of Individual [Axis] Title of Individual [Axis] Title of Individual with Relationship to Entity [Domain] Relationship to Entity [Domain] Senior Manager [Member] Senior Manager [Member] Senior Manager Stock Compensation Plan [Member] Stock Compensation Plan [Member] 2017 and 2015 Options Granted [Member] 2017 and 2015 Options Granted [Member] 2017 and 2015 Options Granted [Member] Right to elect Board of Directors percentage Right To Elect Board Of Directors Percentage Right To Elect Board Of Directors Percentage Shares repurchased by company Treasury Stock, Shares, Acquired Cost of shares repurchased by company Payments for Repurchase of Common Stock Number of shares authorized to be repurchased Stock Repurchase Program, Number of Shares Authorized to be Repurchased Number of shares authorized to be repurchased remaining under previous authorization StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchasedUnderPreviousAuthorization Number of shares authorized to be repurchased remaining under previous authorization. Authorized shares remaining for repurchase Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased Shares reserved for stock awards granted under the plan Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Individual award limit authorization Share-based compensation Arrangement by Share-based Payment Award, Number of Shares Authorized to an Individual The maximum number of shares per individual by year (or other type of equity) originally approved (usually by shareholders and board of directors), not of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to an individual, the shares or units remain authorized and become reserved for issuance under outstanding awards. Shares reserved for issuance Common Stock, Capital Shares Reserved for Future Issuance Shares subject to award outstanding Shares available for future awards Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Number of shares affected by modification of terms Number of employees affected by modification of terms of share awards Incremental stock compensation expense, net of forfeitures, due to modification Share awards outstanding, restriction will lapse in 2018 Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year One Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year One Share awards outstanding, restriction will lapse in 2019 Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year Two Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year Two Share awards outstanding, restriction will lapse in 2020 Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year Three Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year Three Share awards outstanding, restriction will lapse in 2021 Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year Four Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Year Four Number of shares awarded in 2018 Stock-based compensation expense Allocated Share-based Compensation Expense Total unrecognized compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Years over which cost expected to be recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Number of stock options forfeited due to modification Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Options outstanding exercisable now Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Now Options outstanding exercisable now. Options outstanding exercisable in 2018 Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year One Options outstanding exercisable in year one. Options outstanding exercisable in 2019 Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year Two Options outstanding exercisable in year two. Options outstanding exercisable in 2020 Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year Three Options outstanding exercisable in year three. Options outstanding exercisable in 2021 Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year Four Options outstanding exercisable in year four. Options outstanding exercisable in 2022 Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year Five Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year Five Options outstanding exercisable in 2023 Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year Six Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Exercisable Year Six Intrinsic value of options outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Intrinsic value of options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Intrinsic value of options unvested Share Based Compensation Arrangement By Share Based Payment Award Options Unvested Intrinsic Value Share Based Compensation Arrangement By Share Based Payment Award Options Unvested Intrinsic Value Market value of company's stock Common Stock Stated Market Value Per Share Common Stock Stated Market Value Per Share Options unvested, shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares Options unvested, average exercise price Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Nonvested Weighted Average Exercise Price The weighted average price as of the end of the year at which grantees can acquire the shares reserved for issuance under the stock option plan which are not vested. Options unvested, weighted average remaining contractual term, years Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Nonvested Weighted Average Remaining Contractual Term The weighted average period between the balance sheet date and expiration for all awards outstanding but not vested under the plan, which may be expressed in a decimal value for number of years. Exercised, Number of Shares Intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Tax benefit from stock option exercises Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options Number of shares granted Weighted average fair value, granted options Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Fair value of company common stock Fair Value Of Company Common Stock Fair value of company common stock Stock options outstanding Accrual balance related to stock based compensation Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent Stock compensation payouts Deferred Compensation Arrangement with Individual, Distribution Paid Shares excluded from earnings per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Dividends declared per common share Common Stock, Dividends, Per Share, Declared Conversion of stock from Class A to Class B, percentage Percentage Of Conversion From One Class Of Stock To Another Percentage Of Conversion From One Class Of Stock To Another Conversion of Class A shares to Class B Conversion of Stock, Shares Converted Document and Entity Information [Abstract] Document and Entity Information [Abstract] Entities [Table] Entities [Table] Entity Information [Line Items] Entity Information [Line Items] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Schedule of Product Information [Table] Schedule of Product Information [Table] JacksonvilleFL [Member] JacksonvilleFL [Member] JacksonvilleFL [Member] Product Information [Line Items] Product Information [Line Items] Number of education business categories Number Of Education Business Categories Number of categories that comprise Kaplan's businesses Activity Related to Stock Awards Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Activity Related to Stock Options Share-based Compensation, Stock Options, Activity [Table Text Block] Information related to Stock Options Outstanding and Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding and Exercisable [Table Text Block] Fair Value of Options Assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Summary of Earnings Per Share from Continuing Operations, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Antidilutive Weighted Average Restricted Stock and Options [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Axis] Operating Loss Carryforward Period [Domain] 2018 [Member] Loss Carry Forwards Expirations Year One [Member] Loss Carry Forwards Expirations Year One Member 2019 [Member] Loss Carry Forwards Expirations Year Two [Member] Loss Carry Forwards Expirations Year Two [Member] 2020 [Member] Loss Carry Forwards Expirations Year Three [Member] Loss Carry Forwards Expirations Year Three Member 2021 [Member] Loss Carry Forwards Expirations Year Four [Member] Loss Carry Forwards Expirations Year Four Member 2022 [Member] Loss Carry Forwards Expirations Year Five [Member] Loss Carry Forwards Expirations Year Five Member 2023 and after [Member] Loss Carry Forwards Expirations After Year Five [Member] Loss Carry Forwards Expirations After Year Five Member Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Income tax loss carryforwards to be fully utilized Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] AOCI Including Portion Attributable to Noncontrolling Interest [Member] AOCI Including Portion Attributable to Noncontrolling Interest [Member] Unrealized Gain (Loss) on Pensions and Other Postretirement Plans [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Other comprehensive (loss) income before reclassifications Net amount reclassified from accumulated other comprehensive income Reclassification of stranded tax effects to retained earnings as a result of tax reform Deferred Tax Valuation Allowance [Member] Valuation Allowance of Deferred Tax Assets [Member] Valuation Allowance [Line Items] Valuation Allowance [Line Items] Tax Expense and Revaluation Valuation Allowances And Reserves, Charged To Cost And Expense And Other Charges Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, charged to costs and expenses and other charges. Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Cash equivalents and other short-term investments [Member] Cash Equivalents And Other Short Term Investments [Member] -- None. No documentation exists for this element. -- U S Federal agency mortgage- backed securities [Member] U S Federal Agency Mortgage Backed Securities [Member] U S Federal Agency Mortgage Backed Securities Member Corporate debt securities [Member] Corporate Debt Securities [Member] Other fixed income securities [Member] Total investments [Member] Total Investments [Member] -- None. No documentation exists for this element. -- Receivables [Member] Receivables [Member] -- None. No documentation exists for this element. -- Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring [Member] Fair Value, Measurements, Recurring [Member] Plan Asset Location [Domain] U.S. [Member] UNITED STATES International [Member] Pension plan assets at fair value Defined Benefit Plan Assets Allocation (Percent) Summary of Other Comprehensive Income (Loss) Comprehensive Income (Loss) [Table Text Block] Summary of Changes in Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Summary of Amounts and Line Items of Reclassifications out of Accumulated Other Comprehensive Income (Loss) Disclosure of Reclassification Amount [Text Block] Summary of Other Non-Operating Income (Expense) Schedule of Other Nonoperating Income (Expense) [Table Text Block] Operating revenues Disposal Group, Including Discontinued Operation, Revenue Operating costs and expenses Disposal Group, Including Discontinued Operation, Operating Expense Operating income Disposal Group, Including Discontinued Operation, Operating Income (Loss) Non-operating expense Disposal Group, Including Discontinued Operation, Other Non-Operating Income (Expense) Amount of other non-operating income (expense) attributable to disposal group, including, but not limited to, discontinued operation. Income from discontinued operations Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax Provision for income taxes Discontinued Operation, Tax Effect of Income (Loss) from Discontinued Operation During Phase-out Period Net Income from Discontinued Operations Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax Loss on disposition of discontinued operations Provision for income taxes on disposition of discontinued operations Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation Income from Discontinued Operations, Net of Tax Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Beginning unrecognized tax benefits Unrecognized Tax Benefits Increases related to current year tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Increases related to prior year tax positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Decrease related to prior year tax positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Decreases related to settlement with tax authorities Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Decreases due to lapse of applicable statute of limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Ending unrecognized tax benefits Quarterly Impact of Certain Items [Table] Quarterly Impact of Certain Items [Table] Quarterly Impact of Certain Items [Table] Quarterly Impact of Certain Items [Line Items] Quarterly Impact of Certain Items [Line Items] Quarterly Impact of Certain Items [Line Items] Restructuring and Non-Operating Separation Incentive Program Charges, after tax Restructuring And Related Charges, Net of Tax Restructuring costs and related charges, including early retirement program expenses, after tax. Earnings Per Share, Diluted, Restructuring And Non-Operating Separation Incentive Program Charges Earnings Per Share, Diluted, Restructuring And Related Charges Earnings Per Share, Diluted, Restructuring and Related Charges Net Goodwill and other long-lived assets impairment, after tax Impairment Of Goodwill And Other Long-Lived Assets, Net of Tax Goodwill and other long-lived asset impairment, after tax Earnings Per Share, Diluted, Impairment of Goodwill and other long-lived assets Earnings Per Share, Diluted, Impairment Of Goodwill And Other Long-Lived Assets Earnings Per Share, Diluted, Impairment Of Goodwill And Other Long-Lived Assets Non-operating unrealized foreign currency gains (losses), after tax Foreign Currency Transaction Gain (Loss), Unrealized, Net of Tax Foreign Currency Transaction Gain (Loss), After Tax Earnings Per Share, Diluted, Foreign Currency Transaction Gain (Loss), Unrealized Earnings Per Share, Diluted, Foreign Currency Transaction Gain (Loss), Unrealized Earnings Per Share, Diluted, Foreign Currency Transaction Gain (Loss), Unrealized Net nonrecurring deferred tax benefit adjustment Net Deferred Tax Benefit Net nonrecurring deferred tax benefit adjustment. Earnings Per Share, Diluted, Net Deferred Tax Benefit Earnings Per Share, Diluted, Net Deferred Tax Benefit Net nonrecurring deferred tax benefit adjustment, per share. Earnings Per Share, Diluted, Effective Income Tax Rate Reconciliation, share-based compensation Earnings Per Share, Diluted, Effective Income Tax Rate Reconciliation, Share-based Compensation Excess Tax Benefit Earnings Per Share, Diluted, Effective Income Tax Rate Reconciliation, share-based compensation, excess tax benefit amount Non-operating Settlement Gain, after tax Settlement Gain Net Of Tax Settlement gain related to a bulk lump sum pension offering, net of tax. Earnings Per Share, Diluted, Non-operating Settlement Gain Earnings Per Share Diluted Settlement Gain Settlement gain related to a bulk lump sum pension offering, per share. Net non-operating gain (loss) from the sales of land and marketable equity securities, after tax Nonoperating Gain Loss From Sales Of Land And Marketable Equity Securities Net Of Tax Non-operating gain (loss) from sales of land and marketable equity securities, net of tax. Earnings Per Share, Diluted, Nonoperating Gain Loss From Sales Of Land And Marketable Equity Securities Earnings Per Share, Diluted, Nonoperating Gain Loss From Sales Of Land And Marketable Equity Securities No-noperating gain (loss) from the sales of land and marketable equity securities, per share. Net Non-operating Gain (Loss) Sale Of Businesses And Investments And Formation Of Joint Venture, after tax Net Non-operating Gain (Loss) Sale Of Businesses And Investments And Formation Of Joint Venture Net Of Tax The net non-operating gain (loss) on the sale of five businesses and an Investment and on the formation of a joint venture, net of tax. Earnings Per Share, Diluted, Net Non-operating Gain (Loss) Sale of Businesses And Investments And Formation Of Joint Venture Earnings Per Share, Diluted, Net Non-operating Gain (Loss) Sale of Businesses And Investments And Formation Of Joint Venture The net non-operating gain (loss) on the sale of give businesses and an investment and on the formation of a joint venture, per share. Non-operating expense from the write-down of cost and equity method investments, after tax Nonoperating Expense Writedown Of Cost And Equity Method Investments Net Of Tax The non-operating expense from the write-down of cost and equity method investments, net of tax. Earnings Per Share, Diluted, Nonoperating Expense Writedown Of Cost And Equity Method Investments Earnings Per Share, Diluted, Nonoperating Expense Writedown Of Cost And Equity Method Investments The non-operating expense from the write-down of cost and equity method investments, per share. Gain on sale of land, after tax Gain On Sale Of Land Net Of Tax The gain on sale of land, after tax. Redeemable Preferred Stock Temporary Equity [Text Block] Reedemable Preferred Stock Text Block Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Accounting Standards Update 2016-01 [Member] Accounting Standards Update 2016-01 [Member] Accounting Standards Update 2018-02 [Member] Accounting Standards Update 2018-02 [Member] ASU 2018-02 Income Statement - Reporting Comprehensive Income (Topic 220) Accounting Standards Update 2014-09 [Member] Accounting Standards Update 2014-09 [Member] Reclassification of stranded tax effects to retained earnings as a result of tax reform Cumulative Effect of New Accounting Principle in Period of Adoption Cumulative Effect of New Accounting Principle in Period of Adoption Summary of Quarterly Operating Results and Comprehensive Income (Unaudited) Quarterly Financial Information [Text Block] Schedule of Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Axis] Schedule of Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Axis] Financial Instruments Subject to Mandatory Redemption, Financial Instrument [Domain] Financial Instruments Subject to Mandatory Redemption, Financial Instrument [Domain] Securities Subject to Mandatory Redemption [Member] Securities Subject to Mandatory Redemption [Member] Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, First Anniversary [Member] Debt Instrument, Redemption, Period One [Member] Debt Instrument, Redemption, Second Anniversary [Member] Debt Instrument, Redemption, Period Two [Member] Debt Instrument, Redemption, Third Anniversary [Member] Debt Instrument, Redemption, Period Three [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] London Interbank Offered Rate (LIBOR) [Member] London Interbank Offered Rate (LIBOR) [Member] Eurodollar [Member] Eurodollar [Member] Federal Funds Effective Swap Rate [Member] Federal Funds Effective Swap Rate [Member] Four-Year Revolving Credit Agreement Dated, June 17, 2011 [Member] Four Year Revolving Credit Agreement Dated June Seventeenth Two Thousand Eleven [Member] Four-Year Revolving Credit Agreement Dated, June Seventeenth Two Thousand Eleven [Member]. Five-Year Revolving Credit Agreement Dated June 29, 2015 [Member] Five Year Revolving Credit Agreement Dated June Twenty-nine Two Thousand Fifteen [Member] Five-year Revolving Credit Agreement dated June 29, 2015 [Member] USD $450 million portion of Revolver [Member] Four Hundred Fifty Million U S Dollar Portion Of Revolver [Member] -- None. No documentation exists for this element. -- AUD $50 million portion of Revolver [Member] Fifty Million Australian Dollar Portion Of Revolver [Member] AUS $50 Million Borrowing Interest Rate Swap [Member] Interest Rate Swap [Member] Other Indebtedness [Member] Other Indebtedness [Member] Other Indebtedness [Member] Interest rate of debt instrument Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Maturity year, start Debt Instrument, Maturity Date Range, Start Debt Instrument, Maturity year, end Debt Instrument, Maturity Date Range, End Debt Instrument Price Percentage Of Outstanding Balance Redeemed Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Covenant, Leverage Ratio, Maximum Debt Instrument, Covenant, Leverage Ratio, Maximum Maximum leverage ratio required to be maintained under Credit Agreement. Covenant, Interest Coverage Ratio, Minimum Debt Instrument, Covenant, Interest Coverage Ratio, Minimum Minimum consolidated interest coverage ratio based upon the ratio of consolidated adjusted EBITDA to consolidated interest expense as determined pursuant to the Credit Agreement. Line of Credit Notional amount of cash flow hedge Derivative, Notional Amount Derivative, Fixed Interest Rate Derivative, Fixed Interest Rate Interest rate swap percentage rate Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate Basis Spread on Variable Rate Debt Instrument, Basis Spread on Variable Rate Debt Instrument, Maturity date Debt Instrument, Maturity Date Notes repurchase percentage of principal amount to be eligible for redemption Notes repurchase percentage of principal amount to be eligible for redemption Notes Repurchase Percentage Of Principal Amount To Be Eligible For Redemption Current borrowing capacity Line of Credit Facility, Current Borrowing Capacity Unused Capacity, Commitment Fee Percentage Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Average borrowings outstanding Average Outstanding Debt Amount Average borrowings outstanding during the period, both short and long term. Weighted average interest rate of borrowings Debt Instrument, Interest Rate During Period Net interest expense incurred Interest Expense, Debt Fair value of debt instrument Debt Instrument, Fair Value Disclosure Carrying value of debt instrument Types of interest rate derivatives used Types of Interest Rate Derivatives Used Proceeds from (Repayments of) Lines of Credit Proceeds from (Repayments of) Lines of Credit Notional amount of derivative matured Notional Amount Of Derivative Matured The notional amount of a derivative that matured. Expressed in absolute value. Termination Of Credit Agreement Termination Of Credit Agreement Reflects the amount of the credit facility terminated by the Company. Statement of Cash Flows [Abstract] Cash Flows from Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation, amortization and goodwill and other long-lived asset impairment Depreciation, Depletion, Amortization And Impairment The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets, including write-downs for impairments. Net pension benefit Net pension benefit Net Periodic Benefit For Defined Benefit Pension Plans Excluding Early Retirement Program, Special Separation Benefit Expense And Settlement Including Spinoff Curtailment The net periodic benefit or expense for defined benefit pension plans excluding the early retirement program and special separation benefit expense, curtailment, settlement and other programs separately disclosed in the financial statements. This element includes the curtailment related to the spin-off of a business. Stock-based compensation expense, net Share-based Compensation Foreign exchange (gain) loss Net loss (gain) on sales and disposition of businesses Net Gain Loss On Sales And Disposition of Businesses Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment. Net loss on dispositions, sales or write-downs of marketable equity securities and cost method investments Gain (Loss) on Disposition of Assets Net loss on dispositions, sales or write-downs of marketable equity securities and cost method investments Marketable Securities And Cost Method Investments Realized Gain Loss This item represents the net total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting. This item also includes losses recognized for other than temporary impairments (OTTI) of the marketable securities and cost method investments. Gain on sale of an equity affiliate Equity in losses of affiliates, net of distributions Income (Loss) from Equity Method Investments, Net of Dividends or Distributions Equity in losses of affiliates, net of distributions Income Loss From Equity Method Investments Net Of Dividends Or Distributions Including Impairment This element represents the undistributed income (or loss) of equity method investments, net of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations; such investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities. This element also includes impairment charges recorded. (Benefit from) provision for deferred income taxes Deferred Income Tax Expense Benefit Including Discontinued Operations The component of income tax expense for the period representing the increase (decrease) in the entity's deferred tax assets and liabilities. Net loss (gain) on sales or write-downs of property, plant and equipment GainLossOnSaleOrWritedownOfPropertyPlantEquipment Amount of gain (loss) on sale, disposal or write-down of property, plant and equipment assets. Change in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable, net Increase (Decrease) in Accounts Receivable Inventories Increase (Decrease) in Inventories Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Income taxes receivable/payable Increase (Decrease) in Income Taxes Other assets and other liabilities, net Increase (Decrease) in Other Operating Assets and Liabilities, Net Other Other Operating Activities, Cash Flow Statement Net Cash Provided by Operating Activities Net Cash Provided by (Used in) Operating Activities Cash Flows from Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Investments in certain businesses, net of cash acquired Investments in equity affiliates, cost method and other investments Payments To Acquire Equity Method Cost Method Investments And Other Investments The cash outflow associated with the purchase of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence, cost method investments or other investments, not including marketable equity securities. Purchases of property, plant and equipment Payments to Acquire Property, Plant, and Equipment Disbursement of loan to affiliate Payments to Fund Long-term Loans to Related Parties Return of investment in equity affiliate Proceeds from Equity Method Investment, Distribution, Return of Capital Net proceeds from sales of businesses, property, plant and equipment and other assets Net Proceeds From Sale Of Businesses Property Plant And Equipment And Other Assets The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period. Also included is the cash inflow from the sale of long-lived, physical assets and other assets. Purchases of marketable equity securities Investments in equity affiliates and cost method investments Payments To Acquire Equity Method And Cost Method Investments The cash outflow associated with the purchase of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence or cost method investments. Investments in commercial paper Investments In Commercial Paper Cash outflow from investments in commercial paper. Proceeds from maturities of commercial paper Proceeds From Maturities Of Commercial Paper Cash inflow from maturities of commercial paper. Other Payments for (Proceeds from) Other Investing Activities Net Cash Used in Investing Activities Net Cash Provided by (Used in) Investing Activities Cash Flows from Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Common shares repurchased Dividends paid Payments of Ordinary Dividends Proceeds from (repayments of) bank overdrafts Proceeds from (Repayments of) Bank Overdrafts Repayments of borrowings Proceeds from (Repayments of) Debt Deferred payments of acquisition and noncontrolling interest Deferred Payments Of Acquisition And Noncontrolling Interest Deferred payments made related to acquisitions and noncontrolling interest. Proceeds from exercise of stock options Proceeds from Stock Options Exercised Issuance of borrowings Proceeds from Issuance of Long-term Debt Cash distributed to Cable ONE in spin-off Payment Of Distribution To Affiliate Cash distribution from the Company to an affiliate. Purchase of noncontrolling interest Payments for Repurchase of Redeemable Noncontrolling Interest Excess tax benefit on share-based payment awards Excess Tax Benefit from Share-based Compensation, Financing Activities Redemption of redeemable preferred stock Payments of financing costs Payments of Financing Costs Other Proceeds from (Payments for) Other Financing Activities Net Cash (Used in) Provided by Financing Activities Net Cash Provided by (Used in) Financing Activities Effect of Currency Exchange Rate Change Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Net Decrease in Cash and Cash Equivalents and Restricted Cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash and Cash Equivalents and Restricted Cash at Beginning of Year Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash and Cash Equivalents and Restricted Cash at Beginning of Year, Including Discontinued Operations Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations Cash and Cash Equivalents and Restricted Cash at End of Year Cash and Cash Equivalents and Restricted Cash at End of Year, Including Discontinued Operations Supplemental Cash Flow Information Supplemental Cash Flow Information [Abstract] Cash paid during the year for: Cash Paid During The Year For: [Abstract] -- None. No documentation exists for this element. -- Income taxes Income Taxes Paid, Net Interest Interest Paid Summary of Fair Value, Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Schedule of Accounts Receivable Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Schedule of Changes in Allowance for Doubtful Accounts and Returns and Allowance for Advertising Rate Adjustments and Discounts Schedule Of Changes In Allowance For Doubtful Accounts And Returns Allowance For Advertising Rate Adjustments And Discounts [Table Text Block] Tabular disclosure of Changes in Allowance for Doubtful Accounts and Returns Allowance for Advertising Rate Adjustments and Discounts Schedule of Accounts Payable and Accrued Liabilities Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Assets Assets [Abstract] Money market investments Money Market Funds, at Carrying Value Commercial paper Commercial Paper Total Unsecured short-term debt instrument issued by corporations which are highly liquid investments that are readily convertible to know amounts of cash. Other current investments Other Short-term Investments Total Financial Assets Investments, Fair Value Disclosure Liabilities Liabilities [Abstract] Deferred compensation plan liabilities Deferred Compensation Liability, Current and Noncurrent Interest rate swap Interest Rate Cash Flow Hedge Liability at Fair Value Mandatorily Redeemable Noncontrolling Interest Mandatorily Redeemable Noncontrolling Interest Fair Value Disclosure Fair value of the Noncontrolling interest that an entity is required to redeem for cash or other assets at a fixed or determinable date or upon the occurrence of an event. Total Financial Liabilities Financial Liabilities Fair Value Disclosure Expected return on assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Amortization of prior service cost (credit) Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Recognized actuarial loss (gain) Defined Benefit Plan, Amortization of Gain (Loss) Net Periodic Cost (Benefit) for the Year Curtailment Settlement Early retirement programs and special separation benefit expense Total Cost (Benefit) for the Year Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Current year actuarial gain (loss) Current year prior service cost Amortization of prior service credit (cost) Recognized net actuarial gain (loss) Curtailments and settlements Total Recognized in Other Comprehensive Income (Before Tax Effects) Total Recognized in Total (Benefit) Cost and Other Comprehensive Income (Before Tax Effects) Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax Fair Value Measurements [Abstract] Fair Value Measurements [Abstract] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Actuarial (gain) loss recognition Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year Prior service cost (credit) recognition Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Contingencies Commitments and Contingencies Disclosure [Text Block] Discount rate (percent) Rate of compensation increase (percent) Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Inventory Disclosure [Text Block] Inventory Disclosure [Text Block] Impairment of intangible assets Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill) Income Tax Expense (Benefit), Continuing Operations [Abstract] Income Tax Expense (Benefit), Continuing Operations [Abstract] U.S. Federal, Current Current Federal Tax Expense (Benefit) State and Local, Current Current State and Local Tax Expense (Benefit) Non-U.S. Current Foreign Tax Expense (Benefit) Total income tax, Current Current Income Tax Expense (Benefit) U.S. Federal, Deferred Deferred Federal Income Tax Expense (Benefit) State and Local, Deferred Deferred State and Local Income Tax Expense (Benefit) Non-U.S. Deferred Foreign Income Tax Expense (Benefit) Total income tax, Deferred U.S. Federal, Total Federal Income Tax Expense (Benefit), Continuing Operations State and Local, Total State and Local Income Tax Expense (Benefit), Continuing Operations Non-U.S. Foreign Income Tax Expense (Benefit), Continuing Operations Current Assets Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash Restricted Cash and Cash Equivalents Investments in marketable equity securities and other investments Investments In Marketable Equity Securities And Other Investments Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale which are intended to be held for less than one year or the normal operating cycle, whichever is longer. Also includes other current investments such as mutual funds. Accounts receivable, net Income taxes receivable Income Taxes Receivable, Current Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Current Inventories and contracts in progress Other current assets Other Assets, Current Total Current Assets Assets, Current Property, Plant and Equipment, Net Goodwill, Net Indefinite-Lived Intangible Assets Amortized Intangible Assets, Net Deferred Income Taxes Deferred Tax Assets, Net Total Assets Liabilities and Equity Liabilities and Equity [Abstract] Current Liabilities Liabilities, Current [Abstract] Accounts payable and accrued liabilities Deferred revenue Deferred Revenue, Current Income taxes payable Accrued Income Taxes, Current Current portion of long-term debt Total Current Liabilities Liabilities, Current Deferred income taxes Deferred Tax Liabilities, Net, Current Postretirement Benefits Other Than Pensions Liability, Other Postretirement Defined Benefit Plan, Noncurrent Accrued Compensation and Related Benefits Deferred Compensation Liability, Classified, Noncurrent Other Liabilities Other Liabilities, Noncurrent Deferred Income Taxes Deferred Tax Liabilities, Net Mandatorily Redeemable Noncontrolling Interest Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value, Amount, Noncurrent Long-Term Debt Total Liabilities Liabilities Commitments and Contingencies (Notes 18 and 19) Commitments and Contingencies Redeemable Noncontrolling Interests Redeemable Preferred Stock, Series A, $1 par value, with a redemption and liquidation value of $1,000 per share; 23,000 shares authorized; none and 10,510 shares issued and outstanding Temporary Equity, Carrying Amount, Attributable to Parent Preferred Stock, $1 par value; 977,000 shares authorized, none issued Preferred Stock, Value, Issued Common Stockholders’ Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Common stock Common Stock, Value, Issued Capital in excess of par value Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income, net of taxes Cumulative foreign currency translation adjustment Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Unrealized gain on available-for-sale securities Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Unrealized gain on pensions and other postretirement plans Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Cash flow hedge Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax Cost of 14,495,506 and 14,423,564 shares of Class B common stock held in treasury Treasury Stock, Value Total Common Stockholders’ Equity Stockholders' Equity Attributable to Parent Noncontrolling Interests Stockholders' Equity Attributable to Noncontrolling Interest Total Equity Total Liabilities and Equity Liabilities and Equity Income Statement [Abstract] Income from Discontinued Operations, Net of Tax Net Income Attributable to Noncontrolling Interests Net income (loss) attributable to Graham Holdings Company common stockholders Investments in Marketable Equity Securities Marketable Securities [Table Text Block] Unrecognized actuarial (gain) loss Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax Unrecognized prior service cost Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax Gross amount Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax Deferred tax liability (asset) Defined Benefit Plan Accumulated Other Comprehensive Income Tax Tax recorded on the defined benefit plan accumulated other comprehensive income. Net amount