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Employee Benefit Plans (Deferred Compensation Plans) (Details) - Deferred Compensation Plans [Member] - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Benefit obligation | $ 3,273 | $ 2,885 | $ 2,539
Interest expense | 285 | 222 | 209
NBCUniversal Media LLC [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Benefit obligation | 858 | 719 | 621
Interest expense | $ 99 | $ 58 | $ 64

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- Definition Deferred compensation plans benefit obligation + References No definition available. + Details
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- Definition Deferred compensation plans interest cost + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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