Revenue (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Jan. 01, 2018 |
Dec. 31, 2017 |
|---|---|---|---|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Prepaid expenses and other current assets | $ 216 | $ 70 | $ 71 |
| Allowance for sales returns | 242 | $ 119 | |
| Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | |||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Prepaid expenses and other current assets | $ 116 |
| X | ||||||||||
- Definition Carrying value as of the balance sheet date of future obligations for sales returns. No definition available.
|
| X | ||||||||||
- 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.
|
| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
|