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Equity, Attributable to Parent, Before Tax

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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- Definition

Fair value of securities received as collateral against derivative assets.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Derivative financial instruments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Notional Amount	$ 32,750		$ 32,750		$ 36,184
Aggregate fair value of derivative financial instruments in asset position	72		72		157
Collateral relating to net asset positions	76		76		157
Cash Flow Hedges
Derivative [Line Items]
Equity, attributable to parent, before tax	85	$ (330)	85	$ (330)	(135)	$ (203)
Clearinghouse Credit Facilities
Derivative [Line Items]
Amount of initial margin posted	247		247		257
Interest Income
Derivative [Line Items]
Change in cash flow hedges derivative instruments, fair value net	(33)	(99)	(86)	(186)
Interest Rate Contracts \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	42,700		42,700		40,500
Foreign exchange and other option and futures contracts \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	1,700		1,700		$ 1,600
Interest rate swap agreements
Derivative [Line Items]
Cash flow hedge reclassification before tax	(44)	$ (113)	(106)	$ (213)
Interest rate swap agreements \| Maturity Period 2025
Derivative [Line Items]
Equity, attributable to parent, before tax	(1)		(1)
Interest rate swap agreements \| Maturity Period 2026
Derivative [Line Items]
Equity, attributable to parent, before tax	(5)		(5)
Interest rate swap agreements \| Maturity Period 2027
Derivative [Line Items]
Equity, attributable to parent, before tax	60		60
Interest rate swap agreements \| Maturity Period 2028
Derivative [Line Items]
Equity, attributable to parent, before tax	$ 31		$ 31