Income Taxes (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
Feb. 28, 2022	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Taxes
Effective tax rate of income (loss) before income taxes		24.30%	22.90%	23.90%	22.80%
New borrowings				$ 5,360	$ 1,707
Excess tax benefits associated with equity-based compensation		$ 2	$ 2	12	11
Equity in net losses of unconsolidated entities		17	11	32	20
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		17	12	31	21
Income tax (expense) benefit, including tax credits, from equity method investment		25	16	48	32
Interest expense		$ 4	$ 3	6	$ 5
Low income housing investments [Member] \| Financing leases and other [Member]
Income Taxes
Note issued	$ 183			$ 183

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

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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

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Amount of the cost of borrowed funds accounted for as interest expense.

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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 value of the noncash (or part noncash) consideration given (for example, liability, equity) in a transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of a transaction not resulting in cash receipts or cash payments in the period.

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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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The cash inflow associated with security instrument that either represents a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes proceeds from (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c).

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Income tax expense (benefit), including federal tax credits, from equity method investment.

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Income Taxes [Line Items]

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