Other Restructuring Reserve, Other Adjustment Restructuring Reserve, Other Adjustment Other items, net Other Nonoperating Income (Expense) Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] 3.45% Senior Notes due 2026 [Member] Senior Notes due October 2026 [Member] Senior Notes due October 2026 at a discount rate of 3.450% Related Party [Axis] Related Party [Axis] Treasury Stock [Member] Treasury Stock [Member] Commitment to invest over next five years Business Combination Five Year Commitment, Total Business Combination Five Year Commitment, Total Segments [Axis] Segments [Axis] Pension and Other Postretirement Benefits Retirement Benefits [Text Block] Cash, cash equivalents and restricted cash at beginning of period (includes $202 (2020) and $120 (2019) of restricted cash) Cash, cash equivalents and restricted cash at end of period (includes $138 (2020) and $122 (2019) of restricted cash, and $6 (2020) of assets held for sale) Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Proceeds from sale of marketable securities Proceeds from Sale and Maturity of Marketable Securities Operating expenses Related Party Transaction, Expenses from Transactions with Related Party Statistical Measurement [Domain] Statistical Measurement [Domain] 5.85% Senior Debentures due 2043 [Member] Senior Debentures Sep 2043 [Member] Senior debentures due in 2043 with a discount rate of 5.850%. LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Credit Facility [Member] Line of Credit [Member] Total purchase price Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Decrease (increase) in the carrying value of debt relating to previously settled fair value hedges Deferred (Gain) Loss on Discontinuation of Fair Value Hedge Number of trustees Number of Trustees Number of Trustees of Chairman Emeritus Trust Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Investments Payments to Acquire Interest in Subsidiaries and Affiliates Deferred income tax liabilities, net Deferred Income Tax Liabilities, Net Revenues by Segment Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Current Fiscal Year End Date Current Fiscal Year End Date Intangible assets, net Intangible Assets, Net (Excluding Goodwill) 2.90% Senior Notes due 2027 [Member] Senior Notes Due 2027 [Member] Senior Notes Due 2027 [Member] Operating income Operating income Operating Income (Loss) Entity Address, Postal Zip Code Entity Address, Postal Zip Code Total current liabilities Liabilities, Current Redeemable Noncontrolling Interest Noncontrolling Interest Disclosure [Text Block] 2.50% Senior Notes due 2023 [Member] Senior Notes Due 2023 2.50 Percent [Member] Senior Notes Due 2023 2.50 Percent [Member] Prepaid and other current assets Prepaid Expense and Other Assets, Current Variable Rate [Domain] Variable Rate [Domain] Variable Rate [Axis] Variable Rate [Axis] 6.875% Senior Debentures due 2036 [Member] Senior Debentures Apr 2036 [Member] Senior debentures due in 2036 with a discount rate of 6.875%. Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Commitments and contingencies Commitments and Contingencies Purchase of Company common stock Payments for Repurchase of Common Stock ASSETS Assets [Abstract] Noncurrent receivables Accounts Receivable, before Allowance for Credit Loss, Noncurrent Period for Consolidated EBITDA Debt Instrument, Period for Consolidated EBITDA Debt Instrument, Period for Consolidated EBITDA Entity Shell Company Entity Shell Company Accounts payable Due to Related Parties, Current Cover [Abstract] Cover [Abstract] Accounts payable Accounts Payable, Current Document Type Document Type 4.85% Senior Debentures due 2034 [Member] Senior Debentures December 2034 [Member] Senior debentures due in December 2034 with a discount rate of 4.850%. Retained earnings Retained Earnings (Accumulated Deficit) Provision for gain on sale of assets Income Tax Expense (Benefit) From Gain On Sale Of Assets Income Tax Expense (Benefit) From Gain On Sale Of Assets Operating lease assets Operating Lease, Right-of-Use Asset NAI ownership of CBS Corp. Class A and Class B Common Stock on a combined basis (percentage) Ownership Percent Of Class A And Class B Stock By Controlling Stockholder Percent of Company Corp. Class A and Class B Common Stock, on a combined basis, owned by controlling stockholder as of the financial statement date Loss on extinguishment of debt Loss on extinguishment of debt Gain (Loss) on Extinguishment of Debt Weighted average useful life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 4.25% Senior Notes due 2023 [Member] Senior Notes Sep 2023 [Member] Senior notes due in 2023 with a discount rate of 4.250%. Released Film, Monetized in Film Group, Capitalized Cost, Released Class B Common Stock purchased (shares) Class B Common Stock purchased (shares) Treasury Stock, Shares, Acquired Common Class B [Member] Common Class B [Member] ViacomCBS stockholders’ equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Fair Value Measurements Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Additional Financial Information Disclosure [Abstract] Additional Financial Information Disclosure [Abstract] Additional Financial Information Disclosure [Abstract] Depreciation of abandoned technology Restructuring and Related Cost, Accelerated Depreciation Long-term debt Total long-term debt, net of current portion Long-term Debt and Lease Obligation New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] AOCI Attributable to Parent, Net of Tax AOCI Attributable to Parent, Net of Tax [Roll Forward] Long Lived Assets Held-for-sale [Line Items] Long Lived Assets Held-for-sale [Line Items] 6.75% Senior Debentures due 2037 [Member] Senior Debentures Oct 2037 [Member] Senior debentures due in Oct 2037 with a discount rate of 6.750%. Net earnings from continuing operations (in dollars per share) Income (Loss) from Continuing Operations, Per Diluted Share Net earnings from discontinued operations (in dollars per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Document Quarterly Report Document Quarterly Report Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Contributions to grantor trust Contributions To Grantor Trust Contributions To Grantor Trust Marketable securities Marketable Securities Other liabilities Other Liabilities, Noncurrent Deferred income tax assets, net Deferred Income Tax Assets, Net Other investing activities Payments for (Proceeds from) Other Investing Activities 4.3% Senior Notes due 2021 [Member] Senior Notes 2021 [Member] Non-designated foreign exchange contracts Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments Released Film, Monetized on Its Own, Capitalized Cost, Released Stock-based compensation activity APIC, Share-based Payment Arrangement, Increase for Cost Recognition Effect of exchange rate changes on cash, cash equivalents and restricted cash Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Segment Reconciling Items [Member] Segment Reconciling Items [Member] Programming and other inventory Less current portion Inventory, Net ViacomCBS Credit Facility [Member] ViacomCBS Credit Facility [Member] ViacomCBS Credit Facility [Member] Revenues Revenue from Contract with Customer, Excluding Assessed Tax Inventory [Line Items] Inventory [Line Items] Net earnings from continuing operations Net earnings from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest 5.25% Senior Debentures due 2044 [Member] Senior Debentures Apr 2044 [Member] Senior Debentures Apr 2044 [Member] Stock-Based Compensation Expense [Member] Stock-Based Compensation Expense [Member] Stock-Based Compensation Expense [Member] Entity File Number Entity File Number Business Acquisition [Axis] Business Acquisition [Axis] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Inventory [Axis] Inventory [Axis] Deferred revenues Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Statement [Line Items] Statement [Line Items] Forecast [Member] Forecast [Member] Class of Stock [Domain] Class of Stock [Domain] Debt maturity, less than Debt Instrument, Term Document Fiscal Period Focus Document Fiscal Period Focus Other liabilities (noncurrent) Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Merger-related costs Business Combination, Acquisition Related Costs 3.50% Senior Notes due 2025 [Member] Senior Notes Due 2025 [Member] Senior Notes Due 2025 [Member] Statement [Table] Statement [Table] Interest cost Defined Benefit Plan, Interest Cost Statistical Measurement [Axis] Statistical Measurement [Axis] Junior Subordinated Notes Junior Subordinated Notes Type of Restructuring [Domain] Type of Restructuring [Domain] 5.90% Senior Notes due 2040 [Member] Senior Notes 2040 [Member] Credit Facility [Axis] Credit Facility [Axis] Programming costs, acquired programming Entertainment, License Agreement for Program Material, Amortization Expense Fair value of debt Debt Instrument, Fair Value Disclosure Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Film group monetization Film, Monetized in Film Group, Amortization Expense Reconciliation from Basic to Diluted Shares Schedule of Weighted Average Number of Shares [Table Text Block] Deferred compensation Deferred Compensation Liability, Current and Noncurrent Interest income Interest Income, Other Advertising [Member] Advertising [Member] Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Business Combinations [Abstract] Business Combinations [Abstract] Publishing [Member] Publishing [Member] Publishing [Member] Individual Monetization: Film, Capitalized Cost [Abstract] Credit from sale Disposal Group, Not Discontinued Operation, Credit From Sale Disposal Group, Not Discontinued Operation, Credit From Sale Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Noncurrent Asset [Member] Noncurrent Asset [Member] Noncurrent Asset [Member] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Unamortized deferred financing costs Unamortized Debt Issuance Expense Debt Debt Disclosure [Text Block] Acquired libraries Acquired Television Library Carrying amount as of the balance sheet date of acquired television library. SG&A Expenses [Member] Selling, General and Administrative Expenses [Member] In process and other Film, Monetized in Film Group, Capitalized Cost, Production Stock-based Compensation Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Weighted average number of common shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Acquired television program rights, including prepaid sports rights Entertainment, License Agreement for Program Material, Capitalized Cost Noncontrolling interests Noncontrolling Interest Noncontrolling Interest Schedule of Allocation of Purchase Price Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Corporate [Member] Corporate, Non-Segment [Member] Amendment Flag Amendment Flag Tax provision on net actuarial gain (loss) and prior service costs related to pension and other postretirement benefit plans Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Amount borrowed under credit facility Long-term Line of Credit Programming inventory Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory Repayment of notes and debentures Repayments of Debt Reclassifications to net earnings Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent 4.85% Senior Notes due 2042 [Member] Senior Notes 2042 [Member] Number of law firms retained Number Of Law Firms Retained Number Of Law Firms Retained Total programming and other inventory Inventory Total Total current and noncurrent inventory. Net cash flow provided by operating activities Net Cash Provided by (Used in) Operating Activities Related Party [Domain] Related Party [Domain] Restructuring, Impairment, and Other Corporate Matters Restructuring and Related Activities Disclosure [Text Block] Internally produced television programming: Direct-to-television Film Costs [Abstract] Program rights obligations Program Rights Obligations, Noncurrent Number of reporting units tested for goodwill impairment Number of Reporting Units Long Lived Assets Held-for-sale, Name [Domain] Long Lived Assets Held-for-sale, Name [Domain] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Derivative Instrument [Axis] Derivative Instrument [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Total liabilities Disposal Group, Including Discontinued Operation, Liabilities Senior Notes [Member] Senior Notes [Member] Restructuring and other corporate matters Restructuring and other corporate matters Restructuring and other corporate matters Restructuring Charges And Other Restructuring and other corporate matters Programming charges Programming charges Programming Charges Programming Charges Local Phone Number Local Phone Number Lease Income Lease Income [Abstract] Segments [Domain] Segments [Domain] Completed, not yet released Theatrical Film Costs, Completed and Not Released Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] 4.95% Senior Notes due 2031 [Member] Senior Notes Due 2031 [Member] Senior Notes Due 2031 [Member] National Amusements, Inc. [Member] Majority Shareholder [Member] Income Statement Location [Axis] Income Statement Location [Axis] Intangible assets, net Disposal Group, Including Discontinued Operation, Intangible Assets Noncurrent receivables origination in 2018 Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year Income Statement Location [Domain] Income Statement Location [Domain] Average price per share repurchased (in dollars per share) Treasury Stock Acquired, Average Cost Per Share Indefinite-lived Intangible Assets [Line Items] Indefinite-lived Intangible Assets [Line Items] Titles added to existing library Business Combination, Addition Of Titles To Library Business Combination, Addition Of Titles To Library Financing Activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Selling, general and administrative Selling, General and Administrative Expense Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Notional amount of derivative Derivative, Notional Amount Foreign exchange contract [Member] Foreign Exchange Contract [Member] Line of Credit Facility [Table] Line of Credit Facility [Table] 4.375% Senior Debentures due 2043 [Member] Senior Debentures Mar 2043 [Member] Senior debentures due in 2043 with a discount rate of 4.375%. Entity Current Reporting Status Entity Current Reporting Status Other assets Other Assets, Noncurrent Reportable Segments Segment Reporting Disclosure [Text Block] Net earnings from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Cable Networks [Member] Cable Networks Segment [Member] Cable Networks Segment Total Assets Assets Assets Related Parties Related Party Transactions Disclosure [Text Block] Impairment charges Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill) Scenario [Axis] Scenario [Axis] Reclassification of income tax effect of the Tax Reform Act Tax effects reclassified to retained earnings Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Disposal Group Classification [Axis] Disposal Group Classification [Axis] Dispositions costs Business Exit Costs Gain on disposition Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal Subsequent Event Type [Axis] 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Rate Benefit from preparation of tax return Income Tax Expense (Benefit), Preparation Of Tax Return Income Tax Expense (Benefit), Preparation Of Tax Return Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Document Fiscal Year Focus Document Fiscal Year Focus Dividends paid per common share (in dollars per share) Common Stock, Dividends, Per Share, Cash Paid Debt Instrument [Axis] Debt Instrument [Axis] Additional Paid-In Capital [Member] Additional Paid-in Capital [Member] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Operating Segments [Member] Operating Segments [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Number of continuing trusts Number Of Continuing Trusts Number Of Continuing Trusts Variable Interest Entities Variable Interest Entities [Abstract] Variable Interest Entities [Abstract] Class of Stock [Line Items] Class of Stock [Line Items] Class B Common Stock purchased Class B Common Stock purchased Treasury Stock, Value, Acquired, Cost Method Change in assets and liabilities Increase (Decrease) in Operating Capital Balance, beginning of year (shares) Balance, end of year (shares) Shares, Issued Adjustments to reconcile net earnings from continuing operations to net cash flow provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Net earnings from continuing operations (in dollars per share) Income (Loss) from Continuing Operations, Per Basic Share Litigation Case [Axis] Litigation Case [Axis] Foreign currency hedges Foreign Currency Contract, Asset, Fair Value Disclosure Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Revolving Credit Facility [Member] Revolving Credit Facility [Member] Maximum derivative contract term Derivative, Term of Contract 3.375% Senior Notes due 2028 [Member] Senior Notes Due 2028 [Member] Senior Notes Due 2028 [Member] Translation adjustment Temporary Equity, Foreign Currency Translation Adjustments Net earnings Temporary Equity, Net Income Transfer of intangible assets Income Tax Reconciliation, Reorganization Of Foreign Operations Income Tax Reconciliation, Reorganization Of Foreign Operations Subsequent Event [Member] Subsequent Event [Member] Other Bank Borrowings [Member] Notes Payable to Banks [Member] Outstanding letters of credit and surety bonds Letters of Credit Outstanding, Amount Acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Common stock, shares authorized (in shares) Common Stock, Shares Authorized Percentage of interest acquired Business Acquisition, Percentage of Voting Interests Acquired Dilutive effect of shares issuable under stock-based compensation plans Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Less current portion of long-term debt Long-term Debt and Lease Obligation, Current Average market share period Impaired Intangible Asset, Average Market Share Period Impaired Intangible Asset, Average Market Share Period Assets held for sale Assets Held-For-Sale, Noncurrent Assets Held-For-Sale, Noncurrent Released Direct-to-television Film Costs, Released Operating Expense [Member] Operating Expense [Member] Percentage point decrease in effective tax rate Increase (Decrease) In Effective Income Tax Rate Reconciliation, Percent Increase (Decrease) In Effective Income Tax Rate Reconciliation, Percent Document Period End Date Document Period End Date Entity Registrant Name Entity Registrant Name Foreign currency hedges Foreign Currency Contracts, Liability, Fair Value Disclosure Income Statement [Abstract] Income Statement [Abstract] Accumulated Other Comprehensive Loss [Member] AOCI Attributable to Parent [Member] Gain on sale of assets Gain (Loss) on Disposition of Assets 3.375% Senior Notes due 2022 [Member] Senior Notes 2022 [Member] Repayments of short-term debt borrowings, net Proceeds from (Repayments of) Short-term Debt, Maturing in Three Months or Less Operating lease liabilities Operating Lease, Liability, Noncurrent 4.20% Senior Notes due 2032 [Member] Senior Notes Due 2032 [Member] Senior Notes Due 2032 [Member] Net actuarial loss and prior service costs Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Improvements to Accounting for Costs of Films and License Agreements for Program Materials [Member] Accounting Standards Update 2019-02 [Member] Participants’ share and royalties payable Accrued Royalties, Current Variable Interest Entity, Primary Beneficiary [Member] Variable Interest Entity, Primary Beneficiary [Member] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Number of consolidated class action lawsuits Number Of Consolidated Class Action Lawsuits Number Of Consolidated Class Action Lawsuits Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Use of Estimates Use of Estimates, Policy [Policy Text Block] Schedule of Long Lived Assets Held-for-sale [Table] Schedule of Long Lived Assets Held-for-sale [Table] Current Assets: Assets, Current [Abstract] Decrease in uncertain tax positions Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Remaining authorization under repurchase program Stock Repurchase Program, Remaining Authorized Repurchase Amount Consolidated Entities [Axis] Consolidated Entities [Axis] Comprehensive income attributable to ViacomCBS Comprehensive Income (Loss), Net of Tax, Attributable to Parent Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] CNET Media Group [Member] CNET Media Group [Member] CNET Media Group Provision (benefit) from restructuring and other corporate matters, depreciation on abandoned technology and other discrete tax items Income Tax Expense (Benefit) From Restructuring And Other Corporate Matters, Depreciation On Abandoned Technology And Other Discrete Tax Items Income Tax Expense (Benefit) From Restructuring And Other Corporate Matters, Depreciation On Abandoned Technology And Other Discrete Tax Items Payments for debt redemption Early Repayments Of Senior Debt And Subordinated Debt Early Repayments Of Senior Debt And Subordinated Debt Scenario [Domain] Scenario [Domain] Other comprehensive income before reclassifications OCI, before Reclassifications, Net of Tax, Attributable to Parent Number of markets lower than carrying value Number Of Television Markets, Impaired Number Of Television Markets, Impaired Capital expenditures Payments to Acquire Property, Plant, and Equipment Consolidation Items [Domain] Consolidation Items [Domain] Document Information [Line Items] Document Information [Line Items] Entity Tax Identification Number Entity Tax Identification Number Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Accounts receivable Due from Related Parties, Current Depreciation and Amortization [Member] Depreciation And Amortization [Member] Depreciation And Amortization [Member] Equity in loss of investee companies, net of tax Income (Loss) from Equity Method Investments Net earnings (ViacomCBS and noncontrolling interests) Net earnings (ViacomCBS and noncontrolling interests) Net earnings Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Earnings from continuing operations before income taxes and equity in loss of investee companies Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Trading Symbol Trading Symbol In process and other Direct-to-television Film Costs, Production Viacom Credit Facility [Member] Viacom Credit Facility [Member] Viacom Credit Facility [Member] Intangible assets, written down to fair value Indefinite-lived Intangible Assets (Excluding Goodwill), Fair Value Disclosure 5.875% Junior Subordinated Debentures due 2057 [Member] Junior Subordinated Debentures February 2057, 5-Year Hybrid [Member] Junior Subordinated Debentures February 2057, 5-Year Hybrid [Member] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Proceeds from issuance of senior notes Proceeds from Issuance of Senior Long-term Debt Current Programming and Other Inventory Schedule of Inventory, Current [Table Text Block] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Stock-based compensation Stock-based compensation expense, before income taxes Stock-based compensation Share-based Payment Arrangement, Noncash Expense Legal Entity [Axis] Legal Entity [Axis] Equity securities Equity Securities, FV-NI Other financing activities Proceeds from (Payments for) Other Financing Activities Payment of payroll taxes in lieu of issuing shares for stock-based compensation Payment, Tax Withholding, Share-based Payment Arrangement Programming and other inventory Total noncurrent programming and other inventory Inventory, Noncurrent Accounts payable and accrued expenses Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Viacom [Member] Viacom [Member] Viacom Entity [Domain] Entity [Domain] 4.20% Senior Notes due 2029 [Member] Senior Notes Due 2029 [Member] Senior Notes Due 2029 [Member] Unrealized gain Equity Securities, FV-NI, Unrealized Gain Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Total debt Debt and Lease Obligation Service cost Defined Benefit Plan, Service Cost Restricted cash Restricted Cash and Cash Equivalents Maximum Consolidated Leverage Ratio, potential increase Line of Credit Facility, Covenant, Maximum Consolidated Leverage Ratio, Accordion Feature, Increase Line of Credit Facility, Covenant, Maximum Consolidated Leverage Ratio, Accordion Feature, Increase City Area Code City Area Code SMR Trust ownership in NAI Chairman Emeritus Trust Ownership Percentage In Controlling Stockholder Chairman Emeritus trust ownership percentage in controlling stockholder Net earnings from discontinued operations, net of tax Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Total costs and expenses Costs and Expenses NAI ownership of CBS Corp. 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Financial Instruments Derivative Instruments, Gain (Loss) [Table Text Block] Amortization of actuarial loss (gain) Defined Benefit Plan, Amortization of Gain (Loss) RSUs and PSUs Restricted Stock or Unit Expense Net periodic cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Financial Instruments and Fair Value Measurements Fair Value Disclosures [Text Block] Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Derivatives [Line Items] Derivatives, Fair Value [Line Items] Current assets Disposal Group, Including Discontinued Operation, Assets, Current Unusual or Infrequent Item, or Both [Axis] Unusual or Infrequent Item, or Both [Axis] 2.90% Senior Notes due 2023 [Member] Senior Notes Due 2023 2.90 Percent [Member] Senior Notes Due 2023 2.90 Percent [Member] Additional paid-in capital Additional Paid in Capital, Common Stock 4.875% Senior Debentures due 2043 [Member] Senior Debentures June 2043 [Member] Senior debentures due June 2043 with a discount rate of 4.875%. Subsequent Event Type [Domain] Subsequent Event Type [Domain] Derivative [Table] Derivative [Table] Business Acquisition [Line Items] Business Acquisition [Line Items] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Assets: Assets, Fair Value Disclosure [Abstract] Number of beneficiary trustees Number Of Beneficiary Trustees Number Of Beneficiary Trustees Intersegment Eliminations [Member] Intersegment Eliminations [Member] Segment Operating Income (Loss) and Reconciliation to Net Earnings (Loss) Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Proceeds from dispositions Proceeds from Sale of Property, Plant, and Equipment Exit costs [Member] Contract Termination [Member] Released Theatrical Film Costs, Released Retirement Plan Type [Domain] Retirement Plan Type [Domain] 7.875% Senior Debentures due 2030 [Member] Senior Debentures Due 2030 [Member] Senior Debentures Due 2030 Dividends Payments of 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