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Income Taxes - Schedule of Expiration Periods of Deferred Tax Assets (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | ---
Tax Credit Carryforward [Line Items] |  |  |  |
Tax loss carryforwards | $ 3,226 |  |  |
Tax credit carryforwards | 358 |  |  |
Other | 493 |  |  |
Valuation allowance | (2,279) | $ (2,307) | $ (2,121) | $ (2,357)
Deferred tax assets, net | 1,798 | $ 1,798 |  |
Expires within 10 years |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Tax loss carryforwards | 422 |  |  |
Tax credit carryforwards | 278 |  |  |
Other | 0 |  |  |
Valuation allowance | (637) |  |  |
Deferred tax assets, net | 63 |  |  |
Expires within 11-20 years |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Tax loss carryforwards | 580 |  |  |
Tax credit carryforwards | 66 |  |  |
Other | 0 |  |  |
Valuation allowance | (293) |  |  |
Deferred tax assets, net | 353 |  |  |
No expiration |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Tax loss carryforwards | 2,224 |  |  |
Tax credit carryforwards | 14 |  |  |
Other | 424 |  |  |
Valuation allowance | (1,329) |  |  |
Deferred tax assets, net | 1,333 |  |  |
Other |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Tax loss carryforwards | 0 |  |  |
Tax credit carryforwards | 0 |  |  |
Other | 69 |  |  |
Valuation allowance | (20) |  |  |
Deferred tax assets, net | $ 49 |  |  |

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