Statement of Comprehensive Income [Abstract]
Statement [Table]
Statement [Table]
Legal Entity [Axis]
Legal Entity [Axis]
Entity [Domain]
Entity [Domain]
NBCUniversal Media LLC [Member]
NBCUniversal Media LLC [Member]
NBCUniversal Media LLC [Member]
Statement [Line Items]
Statement [Line Items]
Net income
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest
Unrealized gains (losses) on marketable securities, net of deferred taxes
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax
Deferred gains (losses) on cash flow hedges, net of deferred taxes
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax
Amounts reclassified to net income:
Amounts Reclassified To Net Income [Abstract]
Realized (gains) losses on marketable securities, net of deferred taxes
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax
Realized (gains) losses on cash flow hedges, net of deferred taxes
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax
Employee benefit obligations, net of deferred taxes
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax
Currency translation adjustments, net of deferred taxes
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax
Comprehensive income
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock
Net Income (Loss) Attributable To Noncontrolling Interests And Redeemable Subsidiary Preferred Stock
Amount of net (income) loss attributable to noncontrolling interest and dividends on redeemable subsidiary preferred stock.
Net (income) loss attributable to noncontrolling interests
Net Income (Loss) Attributable to Noncontrolling Interest
Other comprehensive (income) loss attributable to noncontrolling interests
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest
Comprehensive income (loss) attributable to Comcast Corporation
Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements or Change in Accounting Principle [Table]
New Accounting Pronouncements or Change in Accounting Principle [Table]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Basis of Presentation
Basis of Accounting, Policy [Policy Text Block]
Recent Accounting Pronouncements
New Accounting Pronouncements, Policy [Policy Text Block]
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table]
Schedule of Business Acquisitions, by Acquisition [Table]
Business Acquisition [Axis]
Business Acquisition [Axis]
Business Acquisition, Acquiree [Domain]
Business Acquisition, Acquiree [Domain]
DreamWorks Animation [Member]
DreamWorks Animation [Member]
Consideration Transferred By Comcast [Axis]
Consideration Transferred By Comcast [Axis]
Consideration Transferred By Comcast [Axis]
Cash Consideration Transferred By Comcast [Domain]
Cash Consideration Transferred By Comcast [Domain]
[Domain] for Cash Consideration Transferred By Comcast [Axis]
Consideration Transferred By Comcast [Member]
Consideration Transferred By Comcast [Member]
Consideration Transferred By Comcast [Member]
Business Acquisition [Line Items]
Business Acquisition [Line Items]
Cash consideration transferred
Business Combination, Consideration Transferred
Business acquisition, price paid per share (in dollars per share)
Business Acquisition, Share Price
Significant Transactions
Significant Transactions [Text Block]
The disclosure of significant transactions entered into or completed during the period.
Supplemental Financial Information [Abstract]
Statement Of Cash Flows Supplemental Information Abstract
Supplemental Financial Information [Table]
Supplemental Financial Information [Table]
Supplemental Financial Information [Table]
Supplemental Financial Information [Line Items]
Supplemental Financial Information [Line Items]
[Line Items] for Supplemental Financial Information [Table]
Capital expenditures incurred but not yet paid
Capital Expenditures Incurred but Not yet Paid
Dividends payable
Dividends Payable
Dividends payable (in dollars per share)
Dividends Payable, Amount Per Share
Share-based Compensation [Abstract]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Award Type [Axis]
Award Type [Axis]
Equity Award [Domain]
Equity Award [Domain]
Restricted share units [Member]
Restricted Stock Units (RSUs) [Member]
Stock options [Member]
Employee Stock Option [Member]
Employee stock purchase plans [Member]
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense
Allocated Share-based Compensation Expense
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Schedule of Long-term Debt Instruments [Table]
Schedule of Long-term Debt Instruments [Table]
Debt Instrument [Axis]
Debt Instrument [Axis]
Debt Instrument, Name [Domain]
Debt Instrument, Name [Domain]
NBCUniversal Enterprise Senior Debt Securities [Member]
Senior Notes [Member]
NBCUniversal Enterprise Credit Facility [Member]
NBCUniversal Enterprise Credit Facility [Member]
Universal Studios Japan Term Loan Maturing March 2022 [Member]
Universal Studios Japan Term Loan Maturing March 2022 [Member]
Universal Studios Japan Term Loan Maturing March 2022 [Member]
Comcast Holdings' ZONES due October 2029 [Member]
Comcast Holdings' ZONES due October 2029 [Member]
Comcast Holdings' ZONES due October 2029 [Member]
Comcast Holdings' ZONES due November 2029 [Member]
Comcast Holdings' ZONES due November 2029 [Member]
Comcast Holdings' ZONES due November 2029
Debt Instrument [Line Items]
Debt Instrument [Line Items]
Principal amount of debt securities subject to guarantee
Guarantee Obligations Current Principal Balance
Principal amount of debt securities subject to guarantee.
Revolving credit facility subject to guarantee
Guarantee Obligations, Line Of Credit Facility
Guarantee Obligations, Line Of Credit Facility
Principal amount of debt securities not subject to guarantee
Non Guarantee Obligations Current Principal Balance
Principal amount of debt instruments not guaranteed by Comcast Corporation, the cable guarantors nor NBCUniversal Media, LLC.
Term loans subject to guarantee
Guarantee Obligations, Term Loans
Guarantee Obligations, Term Loans
Investments [Abstract]
Schedule of Equity Method Investments [Table]
Schedule of Equity Method Investments [Table]
Investment, Name [Axis]
Investment, Name [Axis]
Investment, Name [Domain]
Investment, Name [Domain]
Atairos [Member]
Atairos [Member]
Atairos [Member]
The Weather Channel [Member]
The Weather Channel [Member]
The Weather Channel [Member]
Schedule of Equity Method Investments [Line Items]
Schedule of Equity Method Investments [Line Items]
Purchases of investments
Capital Contribution To VIE
The cash outflow associated with a capital contribution to a VIE accounted for as an equity method investment
Equity in net income (losses) of investees
Income (Loss) from Equity Method Investments
Pretax gain, sale of business
Gain (Loss) on Disposition of Business
Gain on sale of The Weather Channel product and technology businesses
Pretax Gain On Sale Of Business By Investee
Pretax gain recognized as a result of the sale of The Weather Channel's product and technology business to IBM
Other Industries [Abstract]
Film And Television Cost [Table]
Film And Television Cost [Table]
Film And Television Cost [Table]
Film And Television Cost [Line Items]
Film And Television Cost [Line Items]
[Line Items] for Film And Television Cost [Table]
Film And Television Costs
Film And Television Costs Disclosure [Text Block]
Film and Television costs Disclosure [Text Block]
Statement of Financial Position [Abstract]
Class of Stock [Axis]
Class of Stock [Axis]
Class of Stock [Domain]
Class of Stock [Domain]
Class A Common Stock [Member]
Common Class A [Member]
Class B Common Stock [Member]
Common Class B [Member]
Assets
Assets [Abstract]
Current Assets:
Assets, Current [Abstract]
Cash and cash equivalents
Cash and Cash Equivalents, at Carrying Value
Receivables, net
Accounts Receivable, Net, Current
Programming rights
Programming Rights, Current
The current portion of acquired television and cable networks programming rights recorded on the balance sheet. Includes multi-year programming arrangements, acquired movies, series and other programs. Carrying amount is stated at the lower of cost, less accumulated amortization, or net realizable value at the balance sheet date.
Other current assets
Other Assets, Current
Total current assets
Assets, Current
Film and television costs
Film And Television Costs
The carrying amount of owned films, television series and other television productions and noncurrent acquired television and cable networks programming rights recorded on the balance sheet. Owned films, television series and other television production costs include capitalizable production costs, including direct costs, production overhead, print costs, development costs and interest. Film and television rights include multi-year programming arrangements, acquired movies, series and other programs. The carrying amount is stated at the lower of cost, less accumulated amortization, or net realizable/fair value at the balance sheet date.
Investments
Long-term Investments
Property and equipment, net
Property, Plant and Equipment, Net
Franchise rights
Indefinite-Lived Franchise Rights
Goodwill
Goodwill
Other intangible assets, net
Other Intangible Assets, Net
Intangible assets, net
Intangible Assets, Net (Excluding Goodwill)
Other noncurrent assets, net
Other Assets, Noncurrent
Total assets
Assets
Liabilities and Equity
Liabilities and Equity [Abstract]
Current Liabilities:
Liabilities, Current [Abstract]
Accounts payable and accrued expenses related to trade creditors
Accounts Payable, Current
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.
Program obligations
Program Rights Obligations, Current
Deferred revenue
Deferred Revenue, Current
Accrued expenses and other current liabilities
Accrued Liabilities, Current
Note payable to Comcast
Note Payable To Parent
The total amount due to Parent, with respect to cash management arrangements under the matching revolving credit notes, as of the balance sheet date.
Current portion of long-term debt
Debt, Current
Total current liabilities
Liabilities, Current
Long-term debt, less current portion
Long-term Debt and Capital Lease Obligations
Accrued participations, residuals and program obligations
Accrued Participations Residuals And Program Obligations, Noncurrent
The noncurrent amount of participations, residual, royalty expenses and program obligations due to another party. 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.
Deferred income taxes
Deferred Income Tax Liabilities, Net
Other noncurrent liabilities
Other Liabilities, Noncurrent
Commitments and contingencies (Note 10)
Commitments and Contingencies
Redeemable noncontrolling interests
Redeemable Noncontrolling Interest, Equity, Carrying Amount
Equity:
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Preferred stock—authorized, 20,000,000 shares; issued, zero
Preferred Stock, Value, Issued
Common stock
Common Stock, Value, Issued
Additional paid-in capital
Additional Paid in Capital
Retained earnings
Retained Earnings (Accumulated Deficit)
Treasury stock, 872,791,028 Class A common shares
Treasury Stock, Value
Member’s capital
Members' Capital
Accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax
Total NBCUniversal member’s equity
Members' Equity
Total Comcast Corporation shareholders’ equity
Stockholders' Equity Attributable to Parent
Noncontrolling interests
Members' Equity Attributable to Noncontrolling Interest
Noncontrolling interests
Stockholders' Equity Attributable to Noncontrolling Interest
Total equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest
Total equity
Limited Liability Company (LLC) Members' Equity, Including Portion Attributable to Noncontrolling Interest
Total liabilities and equity
Liabilities and Equity
Document and Entity Information [Abstract]
DocumentAndEntityInformationAbstract
Document And Entity Information [Table]
Document And Entity Information [Table]
Document And Entity Information [Table]
Document And Entity Information [Line Items]
Document And Entity Information [Line Items]
[Line Items] for Document And Entity Information [Table]
Entity Registrant Name
Entity Registrant Name
Entity Central Index Key
Entity Central Index Key
Trading Symbol
Trading Symbol
Current Fiscal Year End Date
Current Fiscal Year End Date
Entity Filer Category
Entity Filer Category
Document Type
Document Type
Document Period End Date
Document Period End Date
Document Fiscal Year Focus
Document Fiscal Year Focus
Document Fiscal Period Focus
Document Fiscal Period Focus
Amendment Flag
Amendment Flag
Entity Common Stock, Shares Outstanding
Entity Common Stock, Shares Outstanding
Debt Disclosure [Abstract]
Universal Studios Japan Term Loan Maturing March 2022 [Member]
Former Universal Studios Japan Term Loans [Member]
Former Universal Studios Japan Term Loans [Member]
Former Universal Studios Japan Term Loans [Member]
Total debt
Debt and Capital Lease Obligations
Fair value of debt
Long-term Debt, Fair Value
Debt face amount
Debt Instrument, Face Amount
Repayments of debt
Repayments of Debt
Line of Credit Facility [Table]
Line of Credit Facility [Table]
Credit Facility [Axis]
Credit Facility [Axis]
Credit Facility [Domain]
Credit Facility [Domain]
Revolving Credit Facility [Member]
Revolving Credit Facility [Member]
NBCUniversal Enterprise [Member]
NBCUniversal Enterprise [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility [Line Items]
Amounts available under revolving credit facilities
Line of Credit Facility, Remaining Borrowing Capacity
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment [Table]
Schedule of Segment Reporting Information, by Segment [Table]
Segment Reporting Information [Line Items]
Segment Reporting Information [Line Items]
Financial Data by Business Segment
Segment Reporting Disclosure [Text Block]
Condensed Financial Statements [Table]
Condensed Financial Statements [Table]
Comcast Holdings [Member]
Comcast Holdings [Member]
Comcast Holdings
CCCL Parent [Member]
CCCL Parent [Member]
CCCL Parent
NBCUniversal Media Parent [Member]
NBCUniversal Media Parent [Member]
Consolidated Entities [Axis]
Consolidated Entities [Axis]
Consolidated Entities [Domain]
Consolidated Entities [Domain]
Comcast Parent [Member]
Parent Company [Member]
Subsidiary Issuer [Member]
Subsidiary Issuer [Member]
Guarantor Subsidiaries [Member]
Guarantor Subsidiaries [Member]
Non-Guarantor Subsidiaries [Member]
Non-Guarantor Subsidiaries [Member]
Consolidation Items [Axis]
Consolidation Items [Axis]
Consolidation Items [Domain]
Consolidation Items [Domain]
Reportable Legal Entities [Member]
Reportable Legal Entities [Member]
Elimination and Consolidation Adjustments [Member]
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net cash provided by operating activities
Net Cash Provided by (Used in) Operating Activities
Investing Activities
Net Cash Provided by (Used in) Investing Activities [Abstract]
Net transactions with affiliates
Net transactions with affiliates
Net transactions with affiliates.
Capital expenditures
Payments to Acquire Property, Plant, and Equipment
Cash paid for intangible assets
Payments to Acquire Intangible Assets
Acquisitions and construction of real estate properties
Payments For Acquisitions And Construction Of Real Estate Properties
The cash outflow for the acquisition and construction of buildings (properties) whether for investment or use.
Acquisitions, net of cash acquired
Payments to Acquire Businesses, Net of Cash Acquired
Proceeds from sales of investments
Proceeds From Sales Of Businesses And Investments
The cash inflow associated with the sale of businesses and investments, if any, during the period.
Purchases of investments
Payments to Acquire Investments
Deposits
Deposit
Cash paid for deposits
Other
Payments for (Proceeds from) Other Investing Activities
Net cash provided by (used in) investing activities
Net Cash Provided by (Used in) Investing Activities
Financing Activities
Net Cash Provided by (Used in) Financing Activities [Abstract]
Proceeds from (repayments of) short-term borrowings, net
Proceeds from (Repayments of) Short-term Debt
Proceeds from borrowings
Proceeds from Issuance of Long-term Debt
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
Dividends paid
Payments of Dividends
Purchase of Universal Studios Japan noncontrolling interests
Payments to Acquire Additional Interest in Subsidiaries
Issuances of common stock
Proceeds from Issuance of Common Stock
Distributions to noncontrolling interests and dividends for redeemable subsidiary preferred stock
Distributions To Noncontrolling Interests And Dividends For Redeemable Subsidiary Preferred Stock
The cash outflow related to distributions to noncontrolling interests and dividends for redeemable subsidiary preferred stock.
Other
Proceeds from (Payments for) Other Financing Activities
Net cash provided by (used in) financing activities
Net Cash Provided by (Used in) Financing Activities
Increase (decrease) in cash and cash equivalents
Cash and Cash Equivalents, Period Increase (Decrease)
Cash and cash equivalents, beginning of period
Cash and cash equivalents, end of period
Earnings Per Share [Abstract]
Net Income Attributable to Comcast Corporation
Net Income (Loss) Attributable to Parent
Basic EPS attributable to Comcast Corporation shareholders (in shares)
Weighted Average Number of Shares Outstanding, Basic
Basic earnings per common share attributable to Comcast Corporation shareholders (in dollars per share)
Earnings Per Share, Basic
Effect of dilutive securities:
Dilutive Securities, Effect on Basic Earnings Per Share [Abstract]
Assumed exercise or issuance of shares relating to stock plans (in shares)
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements
Diluted EPS attributable to Comcast Corporation shareholders (in shares)
Weighted Average Number of Shares Outstanding, Diluted
Diluted earnings per common share attributable to Comcast Corporation shareholders (in dollars per share)
Earnings Per Share, Diluted
Cash Payments for Interest and Income Taxes
Supplemental Cash Flow Information [Abstract]
Interest
Interest Paid, Net
Income taxes
Income Taxes Paid, Net
Accumulated Other Comprehensive Income (Loss) [Table]
Accumulated Other Comprehensive Income (Loss) [Table]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on marketable securities
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax
Deferred gains (losses) on cash flow hedges
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax
Unrecognized gains (losses) on employee benefit obligations
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax
Cumulative translation adjustments
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax
Accumulated other comprehensive income (loss), net of deferred taxes
Schedule of Business Acquisitions, by Acquisition
Schedule of Business Acquisitions, by Acquisition [Table Text Block]
Long-term Debt, Type [Axis]
Long-term Debt, Type [Axis]
Long-term Debt, Type [Domain]
Long-term Debt, Type [Domain]
Senior Notes [Member]
Senior 8.875% Notes Due 2017 [Member]
Senior 8.875% Notes Due 2017 [Member]
Senior 8.875% Notes Due 2017 [Member]
Senior 6.50% Notes Due 2017 [Member]
Senior 6.5% Notes Due 2017 [Member]
Senior 6.5% Notes Due 2017 [Member]
Repurchases and repayments of debt
Interest rate
Debt Instrument, Interest Rate, Stated Percentage
Gains (losses) on sales and exchanges of investments, net
Realized Investment Gains (Losses)
Investment impairment losses
Other than Temporary Impairment Losses, Investments
Interest and dividend income
Investment Income, Interest and Dividend
Other, net
Other Investment Income Loss Net
Nonoperating income (losses), net from investment holdings recorded in the income statement that are not separately stated.
Investment income (loss), net
Investment Income, Nonoperating
Related Party Transactions [Abstract]
Schedule of Related Party Transactions, by Related Party [Table]
Schedule of Related Party Transactions, by Related Party [Table]
Related Party Transaction [Line Items]
Related Party Transaction [Line Items]
Related Party Transactions Condensed Financial Statements
Schedule of Related Party Transactions [Table Text Block]
Reconciliation of Adjusted EBITDA from Segments to Consolidated [Table]
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table]
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]
FCC Spectrum [Member]
Licensing Agreements [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Adjusted EBITDA
Adjusted EBITDA
The measure used to evaluate the profitability of operating segments.
Adjustment for legal settlement
Gain (Loss) Related to Litigation Settlement
Depreciation
Depreciation
Amortization
Amortization of Intangible Assets
Other operating gains
Gain (Loss) on Disposition of Assets
Operating costs and expenses
Nonoperating Income (Expense)
Equity And Cost Method Investments [Table]
Equity And Cost Method Investments [Table]
Equity And Cost Method Investments [Table]
Snap [Member]
Snap [Member]
Snap [Member]
Other Fair Value Method Investments [Member]
Other Fair Value Method Investments [Member]
Other Fair Value Method Investments [Member]
Hulu [Member]
Hulu [Member]
Hulu member.
Other Equity Method Investments [Member]
Other Equity Method Investments [Member]
Other Equity Method Investments [Member]
AirTouch [Member]
Air Touch [Member]
Air Touch [Member]
BuzzFeed [Member]
BuzzFeed [Member]
Other Cost Method Investments [Member]
Other Cost Method Investments [Member]
Other Cost Method Investments [Member]
Fair Value, Equity And Cost Method Investments [Line Items]
Fair Value, Equity And Cost Method Investments [Line Items]
[Line Items] for Fair Value, Equity And Cost Method Investments [Table]
Fair value method
Marketable Securities
Equity method
Equity Method Investments
Cost method
Cost Method Investments
Total Investments
Investments
Less: Current investments
Short-term Investments
Noncurrent Investments
Operating Segments [Member]
Operating Segments [Member]
Corporate, Non-Segment [Member]
Corporate, Non-Segment [Member]
Eliminations [Member]
Segment Reconciling Items [Member]
Segments [Axis]
Segments [Axis]
Segments [Domain]
Segments [Domain]
Cable Communications [Member]
Cable Communications [Member]
Cable Communications Member
Cable Networks [Member]
Cable Networks [Member]
Cable Networks Member
Broadcast Television [Member]
Broadcast Television [Member]
Broadcast Television Member
Filmed Entertainment [Member]
Filmed Entertainment [Member]
Filmed Entertainment Member
Theme Parks [Member]
Theme Parks [Member]
Theme Parks Member
NBCUniversal Segments [Member]
NBCUniversal Segments [Member]
Products and Services [Axis]
Products and Services [Axis]
Products and Services [Domain]
Products and Services [Domain]
Residential Video Products And Services [Member]
Residential Video Products And Services [Member]
Residential Video Products And Services [Member]
Residential High-speed Internet Products And Services [Member]
Residential High-speed Internet Products And Services [Member]
Residential High-speed Internet Products And Services [Member]
Residential Voice Products And Services [Member]
Residential Voice Products And Services [Member]
Residential Voice Products And Services [Member]
Business Products And Services [Member]
Business Products And Services [Member]
Business Products And Services [Member]
Advertising Products And Services [Member]
Advertising Products And Services [Member]
Advertising Products And Services [Member]
Other Products And Services [Member]
Other Products And Services [Member]
Other Products And Services [Member]
Franchise And Other Regulatory Fees [Member]
Franchise And Other Regulatory Fees [Member]
Franchise And Other Regulatory Fees [Member]
Number of reportable segments
Number of Reportable Segments
Financial Data by Business Segment
Segment Reporting Information, Profit (Loss) [Abstract]
Revenue
Revenues
Depreciation, Amortization and Other
Depreciation, Amortization And Other
Depreciation, amortization and other. Other includes items included in operating income but excluded from the definition of Adjusted EBITDA.
Operating income
Operating Income (Loss)
Capital Expenditures
Cash Paid for Intangible Assets
Cable segment revenue types as percentage of total cable revenue
Cable Segment Revenue Types As Percentage Of Total Cable Revenue
Cable segment revenue types as percentage of total cable revenue
Gain on sale of spectrum rights
Gain (Loss) on Disposition of Intangible Assets
Charge related to a legal settlement
Commitments and Contingencies Disclosure [Abstract]
Temporary Equity, by Class of Stock [Table]
Temporary Equity, by Class of Stock [Table]
Redeemable Preferred Stock [Member]
Redeemable Preferred Stock [Member]
Fair Value, Hierarchy [Axis]
Fair Value, Hierarchy [Axis]
Fair Value Hierarchy [Domain]
Fair Value Hierarchy [Domain]
Level 2 [Member]
Fair Value, Inputs, Level 2 [Member]
Temporary Equity [Line Items]
Temporary Equity [Line Items]
Fair Value of Redeemable subsidiary preferred stock
Temporary Equity, Fair Value Of Redeemable Subsidiary Preferred Stock
Temporary Equity, Fair Value of our redeemable subsidiary preferred stock.
Loss Contingencies [Table]
Loss Contingencies [Table]
Litigation Status [Axis]
Litigation Status [Axis]
Litigation Status [Domain]
Litigation Status [Domain]
Settled Litigation [Member]
Settled Litigation [Member]
Litigation Case [Axis]
Litigation Case [Axis]
Litigation Case [Domain]
Litigation Case [Domain]
Sprint Communications Company L.P. Lawsuit [Member]
Sprint Communications Company L.P. Lawsuit [Member]
Sprint Communications Company L.P. Lawsuit [Member]
Loss Contingencies [Line Items]
Loss Contingencies [Line Items]
Schedule of Fair Value Method Investments [Table]
Schedule of Fair Value Method Investments [Table]
Schedule of Fair Value Method Investments [Table]
Schedule of Fair Value Method Investments [Line Items]
Schedule of Fair Value Method Investments [Line Items]
[Line Items] for Schedule of Fair Value Method Investments [Table]
Payments to acquire available-for-sale securities
Payments to Acquire Available-for-sale Securities
Contributed investment from Comcast
Member Contribution
Contribution from member including, but not limited to, a business, investment or asset.
Related Party [Axis]
Related Party [Axis]
Related Party [Domain]
Related Party [Domain]
Comcast and Consolidated Subsidiaries [Member]
Comcast And Consolidated Subsidiaries [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business And Basis Of Presentation [Table]
Business And Basis Of Presentation [Table]
Business And Basis Of Presentation [Table]
Condensed Consolidated Financial Statements [Line Items]
Business And Basis Of Presentation [Line Items]
Business And Basis Of Presentation
Condensed Consolidated Financial Statements
Business Description and Basis of Presentation [Text Block]
Income Statement [Abstract]
Costs and Expenses:
Costs and Expenses [Abstract]
Programming and production
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.
Other operating and administrative
Other Operating And Administrative
Other operating and administrative expense recognized in the period not presented separately.
Advertising, marketing and promotion
Marketing and Advertising Expense
Depreciation
Amortization
Other operating gains
Total costs and expenses
Costs and Expenses
Other Income (Expense):
Nonoperating Income (Expense) [Abstract]
Interest expense
Interest Expense
Investment income (loss), net
Equity in net income (losses) of investees, net
Other income (expense), net
Other Nonoperating Income (Expense)
Total other income (expense)
Income tax expense
Income Tax Expense (Benefit)
Net income
Net (income) loss attributable to noncontrolling interests
Net income attributable to Comcast Corporation
Basic earnings per common share attributable to Comcast Corporation shareholders (in dollars per share)
Diluted earnings per common share attributable to Comcast Corporation shareholders (in dollars per share)
Dividends declared per common share (in dollars per share)
Common Stock, Dividends, Per Share, Declared
Schedule Of Intangible Assets [Table]
Schedule Of Intangible Assets [Table]
FCC Spectrum Auction [Line Items]
FCC Spectrum Auction [Line Items]
FCC Spectrum Auction [Line Items]
Proceeds from FCC spectrum auction
Proceeds from Sale of Intangible Assets
Amount of spectrum acquired
Indefinite-Lived Intangible Assets (Excluding Goodwill)
Deposit to acquire intangible asset
Deposit To Acquire Intangible Asset
Deposit paid in a prior period for the right to an intangible asset in a future period.
Supplemental Financial Information
Additional Financial Information Disclosure [Text Block]
Schedule of Cost-method Investments [Table]
Schedule of Cost-method Investments [Table]
AirTouch [Member]
Schedule of Cost-method Investments [Line Items]
Schedule of Cost-method Investments [Line Items]
Number of series of preferred stock
Number of Preferred Stock Series
Number of Preferred Stock Series
Fair value of cost method investment redeemable preferred shares
Fair Value Of Cost Method Investment Redeemable Preferred Shares
The fair value of a cost method investment related to redeemable preferred shares.
Fair value of redeemable preferred shares
Fair Value Of Redeemable Preferred Shares
Fair value of our redeemable subsidiary preferred shares and/or stock
Plan Name [Axis]
Plan Name [Axis]
Plan Name [Domain]
Plan Name [Domain]
Management Grant [Member]
Management Grant [Member]
Management Grant [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
Number of stock options granted (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
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
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
Unrecognized pretax compensation expense on nonvested awards
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized
Statement of Stockholders' Equity [Abstract]
Equity Components [Axis]
Equity Components [Axis]
Equity Component [Domain]
Equity Component [Domain]
Redeemable Noncontrolling Interests and Redeemable Subsidiary Preferred Stock [Member]
Redeemable Noncontrolling Interests And Redeemable Subsidiary Preferred Stock [Member]
Redeemable Noncontrolling Interests and Redeemable Subsidiary Preferred Stock [Member]
Redeemable Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Member]
Member's Capital [Member]
Member's Capital [Member]
Common Stock [Member]
Common Stock [Member]
Additional Paid-in Capital [Member]
Additional Paid-in Capital [Member]
Retained Earnings [Member]
Retained Earnings [Member]
Treasury Stock at Cost [Member]
Treasury Stock [Member]
Accumulated Other Comprehensive Income (Loss) [Member]
AOCI Attributable to Parent [Member]
Noncontrolling Interest [Member]
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance
Beginning balance
Stock compensation plans
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition
Repurchases of common stock under repurchase program and employee plans
Stock Repurchased and Retired During Period, Value
Employee stock purchase plans
Stock Issued During Period, Value, Employee Stock Purchase Plan
Dividends declared
Dividends, Common Stock, Cash
Other comprehensive income (loss)
Other Comprehensive Income (Loss), Net of Tax
Contributions from (distributions to) noncontrolling interests, net
Contributions From And Distributions To Noncontrolling Interests
Contributions from and distributions to noncontrolling interests
Contribution from member
Purchase of Universal Studios Japan noncontrolling interests
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests
Other
Stockholders' Equity, Other
Net income (loss)
Equity Profit Loss
Profit or loss as represented on the statement of changes in equity.
Ending balance
Ending balance
Increase (Decrease) in Temporary Equity [Roll Forward]
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance
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.
Other
Temporary Equity, Other Changes
Net income (loss)
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest
Ending balance
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 other operating gains
Depreciation And Amortization And Gain (Loss) On Disposition Of Assets
Depreciation And Amortization Expense And (Gain) Loss On Disposition Of Assets
Share-based compensation
Share-based Compensation
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.
Equity in net (income) losses of investees, net
Cash received from investees
Proceeds from Equity Method Investment, Distribution
Net (gain) loss on investment activity and other
Gain (Loss) On Investments And Noncash Other Income (Expense) Net
The net realized gain or loss on investments sold during the period and other income (expense), net, which, for cash flow reporting, is a component of proceeds from continuing operations.
Deferred income taxes
Deferred Income Tax Expense (Benefit)
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures:
Increase (Decrease) in Operating Capital [Abstract]
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.
Film and television costs, net
Film And Television Costs Net
Amount of net increase (decrease) in film and television costs.
Accounts payable and accrued expenses related to trade creditors
Increase (Decrease) in Accounts Payable and Accrued Liabilities
Other operating assets and liabilities
Increase (Decrease) in Other Operating Assets and Liabilities, Net
Net cash provided by operating activities
Share-Based Compensation
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]
Statement of Cash Flows [Abstract]
Operating Activities
Acquisitions of real estate properties
Payments to Acquire Buildings
Proceeds from (repayments of) borrowings from Comcast, net
Proceeds From Note Receivable Issued To And Borrowings From Comcast
Represents the cash inflow from borrowings from Comcast for a note receivable issued to Comcast.
Distributions to member
Payments of Capital Distribution
Distributions to noncontrolling interests
Distributions To Noncontrolling Interest Holders
The cash outflow related to distributions to noncontrolling interests.
Unrealized gains (losses) on marketable securities, deferred taxes
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax
Deferred gains (losses) on cash flow hedges, deferred taxes
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax
Realized (gains) losses on marketable securities, deferred taxes
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax
Realized (gains) losses on cash flow hedges, deferred taxes
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax
Employee benefit obligations, deferred taxes
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax
Currency translation adjustments, deferred taxes
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax
Senior 3.15% Notes Due 2028 [Member]
Senior 3.15% Notes Due 2028 [Member]
Senior 3.15% Notes Due 2028 [Member]
Senior 4.00% Notes Due 2047 [Member]
Senior 4.00% Notes Due 2047 [Member]
Senior 4.00% Notes Due 2047 [Member]
Floating Rate Notes Due 2021 [Member]
Floating Rate Notes Due 2021 [Member]
Floating Rate Notes Due 2021 [Member]
Senior 4.45% Notes Due 2047 [Member]
Senior 4.45% Notes Due 2047 [Member]
Senior 4.45% Notes Due 2047 [Member]
Senior 3.0% Notes Due 2024 [Member]
Senior 3.0% Notes Due 2024 [Member]
Senior 3.0% Notes Due 2024 [Member]
Senior 3.3% Notes Due 2027 [Member]
Senior 3.3% Notes Due 2027 [Member]
Senior 3.3% Notes Due 2027 [Member]
Investments in and amounts due from subsidiaries eliminated upon consolidation
Investments in and amounts due from subsidiaries eliminated upon consolidation
Investments in and amounts due from subsidiaries eliminated upon consolidation
Other intangible assets, net
Accrued expenses and other current liabilities
Accrued Expenses And Other Current Liabilities Including Deferred Revenue
Accrued Expenses And Other Current Liabilities Including Deferred Revenue
Other shareholders’ equity
Other stockholders equity
Other stockholders equity.
Film Costs:
Theatrical Film Costs [Abstract]
Released, less amortization
Theatrical Film Costs, Released
Completed, not released
Theatrical Film Costs, Completed and Not Released
In production and in development
Theatrical Film Costs, In Production And In Development
The amount of direct negative costs incurred in the production and development of a theatrical film, as well as allocations of production overhead and capitalized interest. Examples of direct negative costs include costs of story and scenario; compensation of cast, directors, producers, extras, and miscellaneous staff; costs of set construction and operations, wardrobe, and accessories; costs of sound synchronization; rental facilities on location; and postproduction costs such as music, special effects, and editing.
Total film costs
Theatrical Film Costs
Television Costs:
Direct-to-television Film Costs [Abstract]
Released, less amortization
Direct-to-television Film Costs, Released
In production and in development
Direct-to-Television Film Costs, In Production and In Development
The amount of direct negative costs incurred in the production and development of a direct-to-television film, as well as allocations of production overhead and capitalized interest. Examples of direct negative costs include costs of story and scenario; compensation of cast, directors, producers, extras, and miscellaneous staff; costs of set construction and operations, wardrobe, and accessories; costs of sound synchronization; rental facilities on location; and postproduction costs such as music, special effects, and editing.
Total television costs
Direct-to-television Film Costs
Programming rights, less amortization
Programming Rights Less Amortization
The carrying amount of total acquired programming rights, less amortization
Total film costs, television costs and programming rights
Total Film And Television Costs And Programming Rights After Amortization
The carrying amount of owned films, television series and other television productions and the current and noncurrent portion of acquired television and cable networks programming rights recorded on the balance sheet. Owned films, television series and other television production costs include capitalizable production costs, production overhead, interest, development costs and acquired production costs. Film and television rights include multi-year programming arrangements, acquired movies, series and other programs. The carrying amount is stated at the lower of cost, less accumulated amortization, or net realizable/fair value at the balance sheet date.
Less: Current portion of programming rights
Receivables, gross
Accounts Receivable, Gross, Current
Less: Allowance for returns and customer incentives
Returns And Incentives Allowance, Current
A valuation allowance for sales returns and other incentives.
Less: Allowance for doubtful accounts
Allowance for Doubtful Accounts Receivable, Current
Receivables, net
Tax Receivable Agreement [Axis]
Tax Receivable Agreement [Axis]
Tax Receivable Agreement
Tax receivable agreement [Domain]
Tax receivable agreement [Domain]
Tax receivable agreement [Domain]
Tax Receivable Agreement [Member]
Tax Receivable Agreement [Member]
Tax Receivable Agreement [Member]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Axis]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Axis]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Axis]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Domain]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Domain]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Domain]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Member]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Member]
Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Member]
Allocation of Purchase Price
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest [Abstract]
Film and television costs
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Film and Television Costs
Amount of film and television costs acquired at the acquisition date.
Intangible assets
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill
Working capital
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Working Capital
The amount of working capital (current assets less current liabilities, including cash if any) acquired as of the acquisition date.
Debt
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt
Tax receivable agreement
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Tax Receivable Agreement
Amount of liability for a tax receivable agreement acquired at the acquisition date.
Deferred income taxes
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets
Other noncurrent assets and liabilities
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets and Liabilities
The amount of acquisition cost of a business combination allocated to other noncurrent assets and liabilities of the acquired entity not otherwise disclosed separately.
Identifiable net assets (liabilities) acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net
Noncontrolling interests
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value
Cash consideration transferred
Schedule of recognized share-based compensation expense
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]
Revenue:
Revenues [Abstract]
Service revenue
Sales Revenue, Services, Net
Management fee revenue
Management Fees Revenue
Revenue
Condensed Consolidating Balance Sheet
Condensed Balance Sheet [Table Text Block]
Condensed Consolidating Statement of Income
Condensed Income Statement [Table Text Block]
Condensed Consolidating Statement of Cash Flows
Condensed Cash Flow Statement [Table Text Block]
Operating costs and expenses
Other income (expense)
Other Income (Expense) Related Party
Represents all of the intercompany transactions with Comcast Corporation which are included in other income (expense) captions.
Investment Summary
Summary Investment Holdings [Table Text Block]
Investment Income (Loss), Net
Components Of Investment Income Loss Net [Table Text Block]
Tabular disclosure of investment income (loss), including, but not limited to gains on sales and exchanges of investments, other than temporary impairment losses and interest and dividend income.
Property and equipment - accumulated depreciation
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment
Other intangible assets - accumulated amortization
Finite-Lived Intangible Assets, Accumulated Amortization
Preferred stock, shares authorized (in shares)
Preferred Stock, Shares Authorized
Preferred stock, shares issued (in shares)
Preferred Stock, Shares Issued
Common stock, par value (in dollars per share)
Common Stock, Par or Stated Value Per Share
Common stock, shares authorized (in shares)
Common Stock, Shares Authorized
Common stock, shares issued (in shares)
Common Stock, Shares, Issued
Common stock, shares outstanding (in shares)
Common Stock, Shares, Outstanding
Treasury stock (in shares)
Treasury Stock, Shares
Investments
Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]
Computation of diluted EPS
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Film and Television Costs
Schedule Of Film And Television Costs [Table Text Block]
Schedule Of Film And Television Costs [Table Text Block]
Carrying Value of Related Party Contractual Obligation [Member]
Carrying Value Of Related Party Contractual Obligation [Member]
Earnings Per Share
Earnings Per Share [Text Block]
Subsequent Event Type [Axis]
Subsequent Event Type [Axis]
Subsequent Event Type [Domain]
Subsequent Event Type [Domain]
Subsequent Event [Member]
Subsequent Event [Member]
Comcast New Senior 3.969% Notes Due 2047 [Member]
Senior 3.969% Notes Due 2047 [Member]
Senior 3.969% Notes Due 2047 [Member]
Comcast New Senior 3.999% Notes Due 2049 [Member]
Senior 3.999% Notes Due 2049 [Member]
Senior 3.999% Notes Due 2049 [Member]
Comcast New Senior 4.049% Notes Due 2052 [Member]
Senior 4.049% Notes Due 2052 [Member]
Senior 4.049% Notes Due 2052 [Member]
Comcast and NBCUniversal Senior Notes [Member]
Comcast and NBCUniversal Senior Notes [Member]
Comcast and NBCUniversal Senior Notes [Member]
NBCUniversal Senior 6.400% Notes Due 2040 [Member]
Senior 6.400% Notes Due 2040 [Member]
Senior 6.400% Notes Due 2040 [Member]
NBCUniversal 3.999% Notes Due 2049 to Comcast [Member]
3.999% Notes Due 2049 To Comcast [Member]
3.999% Notes Due 2049 To Comcast [Member]
Debt Conversion Description [Axis]
Debt Conversion Description [Axis]
Debt Conversion, Name [Domain]
Debt Conversion, Name [Domain]
Senior Notes Exchange [Member]
Senior Notes Exchange [Member]
Senior Notes Exchange [Member]
Aggregate principal amount issued
Aggregate principal amount of certain series of outstanding notes
Debt Exchange, Amount
The aggregate principal amount of the debt being exchanged in a debt exchange transaction.
Condensed Consolidating Financial Information
Condensed Financial Information of Parent Company Only Disclosure [Text Block]
Stock split, conversion ratio
Stockholders' Equity Note, Stock Split, Conversion Ratio
Schedule of Short-term Debt [Table]
Schedule of Short-term Debt [Table]
Commercial Paper [Member]
Commercial Paper [Member]
Short-term Debt [Line Items]
Short-term Debt [Line Items]
Maximum borrowing under commercial paper programs
Line of Credit Facility, Maximum Borrowing Capacity
Commercial paper outstanding
Commercial Paper
Comcast and Comcast Cable Debt Securities [Member]
Comcast And Comcast Cable Debt Securities [Member]
Counterparty Name [Axis]
Counterparty Name [Axis]
Counterparty Name [Domain]
Counterparty Name [Domain]
Ownership in cable holding company subsidiaries
Ownership In Cable Holding Company Subsidiaries
Represents the Company's ownership in its cable holding company subsidiaries.
Guarantee obligations, maximum capacity
Guarantee Obligations Maximum Capacity Of Credit Facility
Maximum capacity of credit facility subject to cross-guarantee
Related party aggregate principal amount senior notes not subject to guarantee
Related Party Aggregate Principal Amount Senior Notes Not Subject To Guarantee
Represents the related party aggregate principal amount of senior notes not subject to guarantee by NBCUniversal.
Related party credit facility not subject to guarantee
Related Party Credit Facility Not Subject To Guarantee
Represents the related party credit facility not subject to guarantee by NBCUniversal.
Related party liquidation preference preferred stock not subject to guarantee
Related Party Liquidation Preference Preferred Stock Not Subject To Guarantee
Represents the related party liquidation preference of preferred stock not subject to guarantee by NBCUniversal.
Commitments and Contingencies
Commitments and Contingencies Disclosure [Text Block]
Recent Accounting Pronouncements
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]
Schedule of receivables, net
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]
Schedule of accumulated other comprehensive income (loss)
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]
Schedule of adjustments to reconcile net income to net cash provided by operating activities
Schedule Of Adjustments To Reconcile Net Income To Net Cash Provided By Operating Activities [Table Text Block]
Schedule Of Adjustments To Reconcile Net Income To Net Cash Provided By Operating Activities
Schedule of cash payments for interest and income taxes
Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]
Related Party Transactions
Related Party Transactions Disclosure [Text Block]
Universal Studios Japan [Member]
Universal Studios Japan [Member]
Payments to acquire additional interest in noncontrolling interest
Adjustments for New Accounting Pronouncements [Axis]
Adjustments for New Accounting Pronouncements [Axis]
Type of Adoption [Domain]
Type of Adoption [Domain]
Accounting Standards Update 2016-01 [Member]
Accounting Standards Update 2016-01 [Member]
Accounting Standards Update 2016-09 [Member]
Accounting Standards Update 2016-09 [Member]
New accounting pronouncement impact on net income if adopted
New Accounting Pronouncement Impact On Income Statement If Adopted
Represents the amount that would have increased (decreased) our net income attributable to the parent if the new accounting standard was adopted
Decrease in income tax expense
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount
Increase in diluted earnings per share (in dollars per share)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Diluted Earnings Per Share
Net cash provided by operating activities
Net cash provided by (used in) financing activities
Financial Data by Business Segment
Schedule of Segment Reporting Information, by Segment [Table Text Block]
Cable Communications Segment Revenue Sources
Revenue from External Customers by Products and Services [Table Text Block]
Reconciliation of Adjusted EBITDA from Segments to Consolidated
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]
Long-Term Debt
Debt Disclosure [Text Block]