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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Income Tax Contingency [Line Items] |  |  |  |
Percentage of temporary tax differences that reverse within the carryforward period | 3.00% |  |  |
Percentage of deferred tax asset exclusive of reversing temporary differences | 97.00% |  |  |
Foreign tax credits | $ 20 | $ 68 |  |
Increase (decrease) to valuation allowance | 21 | 40 | $ 113 |
Cumulative amount of valuation allowance | 90 |  |  |
Valuation allowance | 1,821 | 1,965 | 2,279 | $ 2,307
Income taxes, net of amounts refunded | $ 104 | $ 50 | $ 53 |
Percentage of the effect of unrecognized tax benefit, if recorded (less than) | 2.00% | 1.00% | 1.00% |
Interest or penalties recognized (less than for 2022 and 2021) | $ 7 | $ 1 | $ 1 |
Income related to accrued interest and penalties (less than for 2022) | 2 | 1 | 3 |
Amount accrued for payment of interest and penalties (less than for 2022 and 2021) | 11 | 1 | 1 |
Other Net State Deferred Tax Asset |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation allowance | 438 |  |  |
Foreign Tax Credit Carryover |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance | 14 | 12 |  |
Domestic Tax Authority |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance | (2) | (1) | 3 |
Domestic Tax Authority | Other Net State Deferred Tax Asset |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance | $ (49) | (142) | 20 |
Foreign Tax Authority | UK Tax Authority |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance |  | $ (6) |  |
Foreign Tax Authority | Switzerland Tax Authority |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance |  |  | $ 8 |

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