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Commitments and Contingencies (Narrative) (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 USD ($) employee | Dec. 31, 2018 USD ($)
Commitment And Contingencies [Line Items] |  |
Operating lease expense inclusive of short-term and variable lease expenses | $ 1,100 |
Weighted average remaining lease term for operating leases | 10 years |
Weighted average discount rate used to calculate operating lease liabilities | 3.74% |
Cash payments for operating leases | $ 914 |
Carrying value of contractual obligation | 1,100 |
Contractual value of a potential obligation | 1,800 |
NBCUniversal Enterprise [Member] |  |
Commitment And Contingencies [Line Items] |  |
Preferred stock redemption value | $ 725 |
NBCUniversal Enterprise [Member] | Redeemable Subsidiary Preferred Stock [Member] |  |
Commitment And Contingencies [Line Items] |  |
Redeemable subsidiary preferred stock, put period | 30 days |
Redeemable subsidiary preferred stock, dividend rate | 5.25% |
Redeemable subsidiary preferred stock, call period | 1 year |
NBCUniversal Enterprise [Member] | Redeemable Subsidiary Preferred Stock [Member] | Level 2 [Member] |  |
Commitment And Contingencies [Line Items] |  |
Temporary equity, fair value of redeemable subsidiary preferred stock | $ 749 | $ 741
NBCUniversal Media LLC [Member] |  |
Commitment And Contingencies [Line Items] |  |
Operating lease expense inclusive of short-term and variable lease expenses | $ 443 |
Weighted average remaining lease term for operating leases | 15 years |
Weighted average discount rate used to calculate operating lease liabilities | 4.06% |
Cash payments for operating leases | $ 271 |
Carrying value of contractual obligation | 1,100 |
Contractual value of a potential obligation | $ 1,800 |
Workforce Subject to Collective Bargaining Arrangements [Member] |  |
Commitment And Contingencies [Line Items] |  |
Number of employees covered under collective bargaining agreements | employee | 9,400 |
Workforce Subject to Collective Bargaining Arrangements [Member] | NBCUniversal Media LLC [Member] |  |
Commitment And Contingencies [Line Items] |  |
Number of employees covered under collective bargaining agreements | employee | 9,400 |
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] |  |
Commitment And Contingencies [Line Items] |  |
Percentage of full-time equivalent employees covered by collective bargaining agreements that have expired or are schedule to expire during the next year | 12.00% |
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] | NBCUniversal Media LLC [Member] |  |
Commitment And Contingencies [Line Items] |  |
Percentage of full-time equivalent employees covered by collective bargaining agreements that have expired or are schedule to expire during the next year | 12.00% |
Sky Limited [Member] |  |
Commitment And Contingencies [Line Items] |  |
Future cash payments related to additional contracts determined to be operating leases |  | $ 804

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