0.750% Notes due 2032 Notes 0.750 percent due 2032 [Member] Notes 0.750% due 2032 [Member] Cash Payments for Interest and Income Taxes Supplemental Cash Flow Information [Abstract] In production and in development Film, Monetized On Its Own, Capitalized Cost, In Production And In Development Amounts of capitalized film cost incurred in production and in development of film predominantly monetized on its own Other Industries [Abstract] Other Industries [Abstract] Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Interest expense Interest expense Interest Expense Net income attributable to Comcast Corporation Net income (loss) Net Income (Loss) Attributable to Parent Consolidated Entities [Axis] Consolidated Entities [Axis] 1.875% Notes due 2036 Notes 1.875 percent due 2036 [Member] Notes 1.875% due 2036 [Member] 9.455% Guaranteed Notes due 2022 Guaranteed Notes 9.455 Percent Due 2022 [Member] Guaranteed Notes 9.455% Due 2022 [Member] Other intangible assets - accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Retained earnings Retained Earnings (Accumulated Deficit) Accrued participations and residuals Accrued Participations And Residuals, Current The total amount of participations, residual and royalty expenses due to another party in less than one year. Royalty expenses are due to content creators, including artists, authors and other talent; participations includes amounts to financial participants in films, including actors, directors, and producers, for contractually defined participations in a film's net profit or gross receipts; residuals include amounts due to unions and guilds. Operating Segments Operating Segments [Member] Restricted Share Units (RSUs) Restricted Stock Units (RSUs) [Member] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Entity Filer Category Entity Filer Category Dividends declared Dividends, Common Stock, Cash Security Exchange Name Security Exchange Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Currency translation adjustments, deferred taxes Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Restricted Cash Restrictions on Cash and Cash Equivalents [Table Text Block] Equity method Equity Method Investments Income Statement [Abstract] Income Statement [Abstract] Entity Registrant Name Entity Registrant Name Sky Sky Limited Segments [Member] Sky Limited [Member] Other noncurrent assets, net Other Assets, Noncurrent Contributions from (distributions to) noncontrolling interests, net Contributions From And Distributions To Noncontrolling Interests Attributable To Temporary Equity Contributions from and (distributions to) noncontrolling interests attributable to temporary equity. Lease Arrangements [Domain] Lease Arrangements [Domain] Lease Arrangements Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Investment, Name [Axis] Investment, Name [Axis] Segments [Axis] Segments [Axis] Less: Current investments Short-term Investments Increase (decrease) in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Entity File Number Entity File Number Total equity Beginning balance Ending balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Income tax expense Income Tax Expense (Benefit) 1.250% Notes due 2040 Notes 1.250 percent due 2040 [Member] Notes 1.250% due 2040 [Member] Theatrical Theatrical [Member] Theatrical [Member] Universal Beijing Resort Term Loans Universal Beijing Resort Term Loans [Member] Universal Beijing Resort Term Loans [Member] Stock compensation plans APIC, Share-based Payment Arrangement, Increase for Cost Recognition 1.500% Notes due 2029 Notes 1.500 percent Due 2029 [Member] Notes 1.500% Due 2029 [Member] Receivables, net Receivables, net Accounts Receivable, after Allowance for Credit Loss, Current Amendment Flag Amendment Flag Proceeds from borrowings Proceeds from Issuance of Long-term Debt Studios Studios Segments [Member] Studios Segments Equity Components [Axis] Equity Components [Axis] Entity Tax Identification Number Entity Tax Identification Number Programming and production Total programming and production costs Programming And Production Costs The amount of expense recognized in the period for costs associated with video programming and content acquisition and production costs. Programming expenses include the fees paid to license the programming distributed to video customers, such as the programming license fees charged by cable networks and fees charged for retransmission of the signals from local broadcast television stations. Production costs include the amortization of owned and acquired programming, sports rights, direct production costs, residual and participation payments, production overhead, costs associated with the distribution of programming to third-party networks and other distribution platforms, and on-air talent costs. It also includes the amortization of capitalized theatrical film production and acquisition costs and distribution expenses. Masergy Masergy [Member] Masergy Investment securing collateralized obligation Less: Investment securing collateralized obligation Investment Securing Collateralized Obligation Carrying amount of investment presented separately as investment securing collateralized obligation that is partially securing an obligation. Document Fiscal Period Focus Document Fiscal Period Focus Total current assets Assets, Current Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Other income (loss), net Other Income Loss Net Nonoperating income (losses), net recorded in the income statement that are not separately stated. Realized (gains) losses reclassified to net income, net of deferred taxes of $(5) and $— Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax Financial Data by Business Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Redemption of subsidiary preferred stock Temporary Equity, Redemption Of Preferred Stock Temporary Equity, Redemption Of Preferred Stock Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Amortization Amortization Amortization of Intangible Assets Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Long-term debt, less current portion Long-term Debt and Lease Obligation Product and Service [Axis] Product and Service [Axis] Cash and Cash Equivalents Schedule of Cash and Cash Equivalents [Table Text Block] Nonmarketable equity securities Equity Securities without Readily Determinable Fair Value, Amount Content licensing Content Licensing [Member] Content Licensing [Member] Business Combination and Asset Acquisition [Abstract] Weighted-average fair value of restricted share units granted (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 Business Acquisition [Axis] Business Acquisition [Axis] Weighted-average fair value of stock options granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Equity Component [Domain] Equity Component [Domain] Other Stockholders' Equity, Other Currency translation adjustments, net of deferred taxes of $247 and $(92) Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Award Type [Domain] Award Type [Domain] Local Phone Number Local Phone Number Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Assets Assets [Abstract] Investments [Abstract] Investments [Abstract] Statement [Line Items] Statement [Line Items] Deferred gains (losses), net of deferred taxes of $(37) and $(19) Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Restricted cash included in other noncurrent assets, net Restricted Cash, Noncurrent Segment Reconciling Items Segment Reconciling Items [Member] Number of restricted share units granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Total investments Investments Preferred stock Preferred Stock, Value, Issued Property and equipment and intangible assets accrued but not yet paid Capital Costs Incurred But Not Yet Paid Future cash outflow to pay for purchases of property and equipment and intangible assets that have occurred. Purchases of investments Payments to Acquire Investments Schedule of recognized share-based compensation expense Share-based Payment Arrangement, Cost by Plan [Table Text Block] Variable Interest Entity, Not Primary Beneficiary Variable Interest Entity, Not Primary Beneficiary [Member] Retained Earnings Retained Earnings [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Advertising, marketing and promotion Marketing and Advertising Expense NBCUniversal NBCUniversal Business Unit [Member] NBCUniversal Business Unit Ownership percentage in variable interest entity Noncontrolling Interest, Ownership Percentage by Parent Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Other Other [Member] Other [Member] Corporate and Other Corporate, Non-Segment [Member] Equity method investments and certain retained distributions Equity Method Investments and Certain Retained Distributions Equity Method Investments and Certain Retained Distributions Segment Reporting [Abstract] Segment Reporting [Abstract] Cash distribution received from equity method investments Proceeds from Equity Method Investment, Distribution Collateralized obligation Collateralized obligation Collateralized Obligation Carrying amount of obligation presented separately as collateralized obligation that is secured by assets. Repurchases of common stock under repurchase program and employee plans Stock Repurchased and Retired During Period, Value Issuances (repurchases) of common stock under repurchase program and employee plans Stock Issued (Repurchased) During Period, Value Stock Issued (Repurchased) During Period, Value Noncash interest expense (income), net Noncash Interest Expense (Income) Net Represents noncash interest expense (income) items as adjustments to reconcile net income (loss) to cash provided by (used in) operating activities. Operating lease assets and liabilities recognized Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Construction of Universal Beijing Resort Payments For Construction Of Theme Park The cash outflow associated with the construction of a theme park. Number of stock options granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Schedule of weighted average common shares outstanding Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Completed, not released Film, Monetized on Its Own, Capitalized Cost, Completed and Not Released Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Principal amount of term loan outstanding Other Long-term Debt Noncurrent deferred revenue (included in other noncurrent liabilities) Deferred Revenue, Noncurrent Comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Title of 12(b) Security Title of 12(b) Security Direct-to-consumer Direct To Consumer [Member] Direct To Consumer [Member] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Atairos Atairos [Member] Atairos [Member] Total assets Assets Assets Marketable equity securities Equity Securities, FV-NI Film and television costs Film, Monetized On Its Own Capitalized Cost, And Entertainment, License Agreement For Program Material, Including Sports Rights Advances Total amounts of capitalized film cost for film predominantly monetized on its own and capitalized cost for rights acquired by broadcaster under license agreement for program material, including sports rights advances. Investment, Name [Domain] Investment, Name [Domain] Plan Name [Domain] Plan Name [Domain] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Basic earnings per common share attributable to Comcast Corporation shareholders (in dollars per share) Earnings Per Share, Basic Interest Interest Paid, Excluding Capitalized Interest, Operating Activities Employee benefit obligations and other, net of deferred taxes of $3 and $2 Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Supplemental Financial Information [Line Items] Supplemental Financial Information [Line Items] Supplemental Financial Information Document Type Document Type Owned Film, Monetized on Its Own, Capitalized Cost Home entertainment and other Home Entertainment And Other [Member] Home Entertainment And Other Revenue Revenue from Contract with Customer [Text Block] Document And Entity Information [Line Items] Document Information [Line Items] Current and noncurrent receivables, net Change In Current And Noncurrent Receivables Net The increase (decrease) during the reporting period in the amount of current and noncurrent receivables. Product and Service [Domain] Product and Service [Domain] Noncontrolling Interests Noncontrolling Interest [Member] Management Grant Management Grant [Member] Management Grant [Member] Schedule of receivables, net Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Cash capital contributions for equity method investments Capital Contribution To VIE The cash outflow associated with a capital contribution to a VIE accounted for as an equity method investment Less: Net income (loss) attributable to noncontrolling interests Net income (loss) Net Income (Loss) Attributable to Noncontrolling Interest Released, less amortization Film, Monetized on Its Own, Capitalized Cost, Released Disaggregation of revenue Disaggregation of Revenue [Table Text Block] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Voice Residential, Voice [Member] Residential, Voice [Member] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Contract acquisition and fulfillment costs (included in other noncurrent assets, net) Capitalized Contract Cost, Net Other balance sheet accounts Schedule Of Other Balance Sheet Accounts [Table Text Block] Schedule Of Other Balance Sheet Accounts [Table Text Block] Film and television costs, net Film And Television Costs Net Amount of net increase (decrease) in film and television costs. Investment Summary Summary Investment Holdings [Table Text Block] Weighted average number of common shares outstanding – basic (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted earnings per common share attributable to Comcast Corporation shareholders (in dollars per share) Earnings Per Share, Diluted Segments [Domain] Segments [Domain] Contributions from (distributions to) noncontrolling interests, net Contributions From And Distributions To Noncontrolling Interests Contributions from and distributions to noncontrolling interests Net income (loss) Net Income (Loss) Attributable to Redeemable Noncontrolling Interest Income taxes Income Taxes Paid, Net Plan Name [Axis] Plan Name [Axis] Comprehensive income attributable to Comcast Corporation Comprehensive Income (Loss), Net of Tax, Attributable to Parent Media Media Segments [Member] Media Segments Business Unit [Domain] Business Unit [Domain] Business Unit [Domain] Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Proceeds from collateralized obligation Proceeds From Collateralized Obligation The cash inflow from amounts received from the issuance of an obligation that is secured by assets and is presented separately as proceeds from collateralized obligation. 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Liabilities and Equity Liabilities and Equity [Abstract] Employee benefit obligations, deferred taxes Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Condensed Consolidated Financial Statements Business Description and Basis of Presentation [Text Block] Dividends payable Dividends Payable Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Investments Noncurrent investments Long-term Investments Cable Communications Cable Communications Business Unit [Member] Cable Communications Business Unit Increase (Decrease) in Temporary Equity [Roll Forward] Increase (Decrease) in Temporary Equity [Roll Forward] Net (gain) loss on investment activity and other Gain (Loss) On Investments And Other Noncash Income (Loss) Net Net (gain) loss on investment activity, including cash received from investees, and other noncash income (loss), net. Realized and unrealized gains (losses) on equity securities, net Equity Securities, FV-NI, Gain (Loss) Entity Interactive Data Current Entity Interactive Data Current Revenues [Abstract] Revenues [Abstract] 2.0% Exchangeable Subordinated Debentures due 2029 Exchangeable Subordinated Debentures 2.0 Percent Due 2029 [Member] Exchangeable Subordinated Debentures 2.0% Due 2029 [Member] Corporate and Other Corporate, Non-Segment, Intersegment Revenue [Member] Corporate, Non-Segment, Intersegment Revenue 0.250% Notes due 2029 Notes 0.250 percent Due 2029 [Member] Notes 0.250 percent Due 2029 Supplemental Financial Information Additional Financial Information Disclosure [Text Block] Distribution Distribution [Member] Distribution Owned Film, Monetized On Its Own, Amortization Expense, Including Participations And Residuals Amount of amortization expense for capitalized film cost for film predominantly monetized on its own and participation and residuals expenses. Financial Data by Business Segment Segment Reporting Information, Profit (Loss) [Abstract] Document Period End Date Document Period End Date Class B Common Stock Common Class B [Member] Cash paid for intangible assets Cash Paid for Intangible Assets Payments to Acquire Intangible Assets Other operating assets and liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Entity Central Index Key Entity Central Index Key Impact of foreign currency on cash, cash equivalents and restricted cash Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Consolidated Entities [Domain] Consolidated Entities [Domain] Universal Beijing Resort Universal Beijing Resort [Member] Universal Beijing Resort [Member] Investments and Variable Interest Entities Investment [Text Block] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Remaining unfunded capital commitment Variable Interest Entity, Reporting Entity Involvement, Unfunded Capital Commitment Variable Interest Entity, Reporting Entity Involvement, Unfunded Capital Commitment Entity Address, State or Province Entity Address, State or Province Property and equipment, net of accumulated depreciation Property, Plant and Equipment, Net Business Unit [Axis] Business Unit [Axis] Business Unit Other noncurrent liabilities Other Liabilities, Noncurrent Current Liabilities: Liabilities, Current [Abstract] 5.50% Notes due 2029 Notes 5.50 Percent Due 2029 [Member] Notes 5.50% Due 2029 [Member] Unrecognized gains (losses) on employee benefit obligations and other Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan And Other, After Tax Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan And Other, After Tax Proceeds from sales of businesses and investments Proceeds From Sales Of Businesses And Investments The cash inflow associated with the sale of businesses and investments, if any, during the period. Acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Long-Term Debt Debt Disclosure [Text Block] Trading Symbol Trading Symbol Broadband Residential, Broadband [Member] Residential, Broadband [Member] Programming and Production Expense Schedule Of Programming And Production Cost [Table Text Block] Schedule Of Programming And Production Cost Unrealized gains (losses) recognized Equity Securities, FV-NI, Unrealized Gain (Loss) Deferred gains (losses) on cash flow hedges AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax Revenue Revenues Film and television content: Film And Television Content [Abstract] Film And Television Content Wireless Residential, Wireless [Member] Residential, Wireless [Member] Number of reportable segments Number of Reportable Segments Cable Communications Cable Communications Segments [Member] Cable Communications Member Redeemable noncontrolling interests Beginning balance Ending balance Redeemable Noncontrolling Interest, Equity, Carrying Amount Document Transition Report Document Transition Report Common stock Common Stock, Value, Issued Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Investment and other income (loss), net Investment and other income (loss), net Nonoperating Income (Expense) 0.000% Notes due 2026 Notes 0.000 percent Due 2026 [Member] Notes 0.000 percent Due 2026 Costs and Expenses: Costs and Expenses [Abstract] Deferred gains (losses) on cash flow hedges, deferred taxes Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax Total carrying value of debt Debt and Lease Obligation Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Commitments and contingencies Commitments and Contingencies Recognized share-based compensation expense Share-based Payment Arrangement, Expense Accumulated other comprehensive income (loss) Accumulated other comprehensive income (loss), net of deferred taxes Accumulated Other Comprehensive Income (Loss), Net of Tax Dividends payable (in dollars per share) Dividends Payable, Amount Per Share Entity Emerging Growth Company Entity Emerging Growth Company Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Supplemental Financial Information [Table] Supplemental Financial Information [Table] Supplemental Financial Information [Table] Programming and Production Costs Entertainment [Text Block] Less: Allowance for doubtful accounts Accounts Receivable, Allowance for Credit Loss, Current Entity Current Reporting Status Entity Current Reporting Status Film and television costs Film, Monetized On Its Own, And Entertainment, License Agreement For Program Material, Including Sports Rights Advances, Capitalized Costs, Noncurrent Amount of capitalized film cost for film predominantly monetized on its own and capitalized cost for rights acquired by broadcaster under license agreement for program material, including sports rights advances, noncurrent. Other investments Other Investments Net income Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Receivables, gross Accounts Receivable, before Allowance for Credit Loss, Current Current portion of long-term debt Debt, Current Restricted cash included in other current assets Restricted Cash, Current Amortization of owned film and television costs Film, Monetized on Its Own, Amortization Expense Ownership [Axis] Ownership [Axis] Class A Common Stock, $0.01 par value Common Class A [Member] Cover [Abstract] Cover [Abstract] Effect of dilutive securities (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Business Combination, Separately Recognized Transactions [Line Items] Business Combination, Separately Recognized Transactions [Line Items] Cash, cash equivalents and restricted cash, beginning of period Cash, cash equivalents and restricted cash, end of period Cash, cash equivalents and restricted cash, end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Total costs and expenses Costs and Expenses Class of Stock [Axis] Class of Stock [Axis] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Treasury stock (in shares) Treasury Stock, Shares Other Other Programming And Production Expense Other Programming And Production Expense Current Assets: Assets, Current [Abstract] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Licensed, including sports rights Entertainment, License Agreement For Program Material, Including Sports Rights Advances, Amortization Expense Amount of amortization expense for rights acquired by broadcaster under license agreement for program material, including sports rights advances. Other Proceeds from (Payments for) Other Financing Activities Investment and Other Income (Loss), Net Components Of Investment And Other Income (Loss), Net [Table Text Block] Tabular disclosure of investment and other income (loss), net, including, but not limited to, equity in net income (losses) of investees, net, realized and unrealized gains (losses) on equity securities, net, and other income (loss), net. Cash flow hedges: Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax [Abstract] Fair value of collateralized obligation Collateralized Obligation, Fair Value Fair value of obligation presented separately as collateralized obligation that is secured by assets. Deferred revenue Deferred Revenue, Current Entity Address, Postal Zip Code Entity Address, Postal Zip Code Weighted-average number of common shares outstanding – diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Cash dividends declared per common share (in dollars per share) Common Stock, Dividends, Per Share, Declared Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Accrued expenses and other current liabilities Accrued Liabilities, Current Hulu Hulu [Member] Hulu member. 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Treasury Stock at Cost Treasury Stock [Member] Ownership [Domain] Ownership [Domain] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Business Combination, Separately Recognized Transactions [Table] Business Combination, Separately Recognized Transactions [Table] Current Fiscal Year End Date Current Fiscal Year End Date 0.250% Notes due 2027 Notes 0.250 percent Due 2027 [Member] Notes 0.250% Due 2027 [Member] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Total fair value of debt Long-term Debt, Fair Value Other current assets Other Assets, Current Statement [Table] Statement [Table] Licensed, including sports advances Entertainment, License Agreement For Program Material, Including Sports Rights Advances, Capitalized Cost Amount of capitalized cost for rights acquired by broadcaster under license agreement for program material, including sports rights advances. Other Payments for (Proceeds from) Other Investing Activities Capital expenditures Capital Expenditures Payments to Acquire Property, Plant, and Equipment Significant Transactions Significant Transactions [Text Block] The disclosure of significant transactions entered into or completed during the period. Sky Sky Limited Business Unit [Member] Sky Limited Business Unit Unrecognized pretax compensation expense on nonvested awards Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Franchise rights Indefinite-Lived Franchise Rights Consolidated variable interest entity's liabilities included in condensed consolidated balance sheet Liabilities Adjusted EBITDA Adjusted EBITDA The measure used to evaluate the profitability of operating segments. Other Temporary Equity, Other Changes Award Type [Axis] Award Type [Axis] Goodwill Goodwill Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Advertising Advertising [Member] Noncontrolling interests Stockholders' Equity Attributable to Noncontrolling Interest Video distribution programming Video Distribution Programming Expense Video Distribution Programming Expense Consolidation Items [Axis] Consolidation Items [Axis] Total Comcast Corporation shareholders’ equity Stockholders' Equity Attributable to Parent Common stock, shares issued (in shares) Common Stock, Shares, Issued Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued City Area Code City Area Code Accounts payable and accrued expenses related to trade creditors Increase (Decrease) in Accounts Payable and Accrued Liabilities 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] Noncurrent receivables, net (included in other noncurrent assets, net) Accounts Receivable, after Allowance for Credit Loss, Noncurrent Schedule of cash payments for interest and income taxes Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Theme Parks Theme Parks Segments [Member] Theme Parks Member Entity Address, City or Town Entity Address, City or Town Repurchases and repayments of debt Repayments of Other Debt Repurchases of common stock under repurchase program and employee plans Payments for Repurchase of Common Stock Owned: Film, Capitalized Cost [Abstract] Schedule of accumulated other comprehensive income (loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Adjustments Adjustments for Items Excluded from Adjusted EBITDA Adjustments represent the impacts of certain events, gains, losses or other charges that are excluded from Adjusted EBITDA Deferred income taxes Deferred Income Tax Expense (Benefit)