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- Definition

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

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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Nominal or face amount used to calculate payment on derivative.

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- Definition

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
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Derivative [Line Items]
Notional Amount	$ 31,625		$ 31,000
Cash Flow Hedges
Derivative [Line Items]
Equity, attributable to parent, before tax	9	$ 9	90	$ (135)
Clearinghouse Credit Facilities
Derivative [Line Items]
Amount of initial margin posted	172		224
Interest Income
Derivative [Line Items]
Change in cash flow hedges derivative instruments, fair value net	5	(53)
Interest Rate Contracts \| Designated as Hedging Instrument \| Fair value hedges:
Derivative [Line Items]
Notional Amount	1,700		1,600
Interest Rate Contracts \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	44,000		43,000
Foreign exchange and other option and futures contracts \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	2,300		$ 2,400
Interest rate swap agreements
Derivative [Line Items]
Cash flow hedge reclassification before tax	1	$ (62)
Interest rate swap agreements \| Maturity Period 2026
Derivative [Line Items]
Equity, attributable to parent, before tax	$ 6