| Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Millions | 12 Months Ended | ||
|---|---|---|---|
| Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
| Current | |||
| Federal | $ 0 | $ 0 | $ 0 | 
| State | 0 | 0 | 2 | 
| Foreign | 0 | 4 | 30 | 
| Total current | 0 | 4 | 32 | 
| Deferred | |||
| Federal | 41 | (475) | 0 | 
| State | 2 | (46) | 0 | 
| Foreign | 0 | 0 | (5) | 
| Total deferred | 43 | (521) | (5) | 
| Total income tax provision (benefit) | $ 43 | $ (517) | $ 27 | 
| X | ||||||||||
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- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
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- Definition Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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| X | ||||||||||
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- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
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- References No definition available. 
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- Definition Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
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- Definition Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
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- Definition Amount of deferred state, local, and federal tax expense (benefit) pertaining to income (loss) from continuing operations. No definition available. 
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| X | ||||||||||
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- Definition Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
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- References No definition available. 
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| X | ||||||||||
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- Definition Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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| X | ||||||||||
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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