Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Income Taxes
Effective tax rate of income (loss) before income taxes	19.20%	18.60%
Tax credits and adjustments	$ 46	$ 37
Equity in net losses of unconsolidated entities	(5)	19
Low income housing investments [Member]
Income Taxes
Investment proportional amortization tax impact	20	20
Income tax benefit from low-income housing investments	27	28
Variable interest entities interest expense	$ 9	$ 6

Amount, before amortization expense, of income tax credit and other tax benefit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

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Interest expense on beneficial interests issued by consolidated variable interest entities.

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Amount of income tax credit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

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Income Taxes [Line Items]

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