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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Other income tax disclosures |  |  |
Effect of unrecognized tax benefit on income tax expense | $ 28 | $ 41 | $ 37
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense | (10) | 2 | $ 3
Net accrued interest and penalties | 12 | $ 23 |
State |  |  |
Other income tax disclosures |  |  |
State NOL carryforwards | 2,058 |  |
Deferred income tax asset for State NOL carryforwards | 90 |  |
Federal |  |  |
Other income tax disclosures |  |  |
Federal NOL carryforward | 170 |  |
Deferred tax asset for Federal NOL carryforward | $ 36 |  |

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