Income Taxes (Detail) - USD ($) $ in Millions		3 Months Ended
Feb. 08, 2022	Mar. 31, 2022	Mar. 31, 2021
Income Taxes
Effective tax rate of income (loss) before income taxes		23.50%	22.70%
New borrowings		$ 2,362
Equity in net losses of unconsolidated entities		15	$ 9
Increase (decrease) to accruals and related deferred taxes		3
Low income housing investments [Member]
Income Taxes
Consideration for investment	$ 253
Investment cash payment	28
Interest payable	42
Increase (decrease) investments in unconsolidated entities	211
Equity in net losses of unconsolidated entities		14	9
Income tax benefit from low-income housing investments		23	$ 16
Low income housing investments [Member] \| Financing leases and other [Member]
Income Taxes
Note issued	$ 183	$ 183

Amount of affordable housing tax credits and other tax benefits recognized.

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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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The increase (decrease) during the period in the amount due for taxes based on the reporting entity's earnings or attributable to the entity's income earning process (business presence) within a given jurisdiction.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount of increase (decrease) in the investments in and advances to affiliates.

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The fair value of notes issued in noncash investing and financing activities.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Income Taxes [Line Items]

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