| Acquisitions - Pro Forma Information (Details) - Pandora - USD ($) $ in Millions | 12 Months Ended | ||
|---|---|---|---|
| Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
| Business Acquisition [Line Items] | |||
| Total revenue | $ 8,046 | $ 7,921 | $ 7,348 | 
| Net income | $ 131 | $ 938 | $ 844 | 
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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 pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Details 
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