| Intangible Assets - Definite Life Intangible Assets (Details) - USD ($) | 12 Months Ended | ||||
|---|---|---|---|---|---|
| Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Oct. 16, 2020 | Jun. 16, 2020 | |
| Definite life intangible assets: | |||||
| Impairment of definite-lived intangible assets | $ 0 | $ 0 | $ 0 | ||
| Amortization of intangible assets | 152,000,000 | 141,000,000 | 23,000,000 | ||
| Loss on restructuring | 24,000,000 | $ 0 | 0 | ||
| Relationship | |||||
| Definite life intangible assets: | |||||
| Amortization of intangible assets | 6,000,000 | ||||
| Trademarks | |||||
| Definite life intangible assets: | |||||
| Amortization of intangible assets | 3,000,000 | ||||
| Talent and Content Contract | |||||
| Definite life intangible assets: | |||||
| Amortization of intangible assets | $ 29,000,000 | ||||
| Simplecast | |||||
| Definite life intangible assets: | |||||
| Intangible assets | $ 12,000,000 | ||||
| Stitcher | |||||
| Definite life intangible assets: | |||||
| Intangible assets | $ 38,000,000 | $ 38,000,000 | |||
| Automatic Labs Inc. | Finite-Lived Intangible Assets | |||||
| Definite life intangible assets: | |||||
| Loss on restructuring | 4,000,000 | ||||
| Retired | |||||
| Definite life intangible assets: | |||||
| Intangible assets | $ 17,000,000 | ||||
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of intangible assets, excluding goodwill, acquired at the acquisition date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount classified as intangible assets, excluding goodwill, attributable to disposal group held for sale or disposed of. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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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. No definition available. 
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- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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