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Income Taxes (Narrative) (Detail) $ in Millions | Aug. 16, 2022 | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
--- | --- | --- | ---
Non Variable Interest Entities [Line Items] |  |  |
NOL carryforward |  | $ 3,900 |
Foreign tax credit |  | 57 |
Unrecognized Tax Benefits |  | 0 | $ 0
Valuation allowance on net deferred tax asset |  | $ 1,200 | $ 1,200
Effective income tax rate reconciliation, alternative minimum tax on the book income of large corporations, percent | 15 |  |
Effective income tax rate reconciliation, excise tax on most stock buybacks, percent. | 1 |  |

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