Summary of Significant Accounting Policies - Allowance for Sales Returns (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Summary of Significant Accounting Policies | |||
| Sales returns, beginning balance | $ 261 | $ 266 | $ 267 |
| Additions, charged to earnings | 2,188 | 2,336 | 2,434 |
| Deductions | (2,149) | (2,341) | (2,435) |
| Sales returns, ending balance | 300 | 261 | 266 |
| Stock-based compensation | $ 64 | $ 71 | $ 88 |
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- Definition Additions, charged to earnings No definition available.
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- Definition Deductions to allowance for sales returns. No definition available.
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- References No definition available.
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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