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Employee Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Deferred Compensation Plans |
Year ended December 31 (in millions) | 2019 |  | 2018 |  | 2017 |
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] |
Deferred Compensation Plans |
Year ended December 31 (in millions) | 2019 |  | 2018 |  | 2017 |
Benefit obligation | $ | 858 |  | $ | 719 |  | $ | 621 |
Interest expense | $ | 99 |  | $ | 58 |  | $ | 64 |

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- Definition Information regarding deferred compensation plans, including benefit obligations and related expense. + 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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