Derivative Instruments and Hedging Activities Disclosure [Line Items]

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- Definition

Value At Risk Assumed Holding Period For Instruments

+ References

No definition available.

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- Definition

VAR confidence level

+ References

No definition available.

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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- Definition

Amount of decrease in the fair value of derivatives recognized in the income statement.

+ References

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

Amount of asset hedged in portfolio layer hedging relationship, expected to be remaining at end of hedging relationship.

+ References

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- Definition

Maximum period of hedging exposure to variability in future cash flow for forecasted transaction of cash flow hedge, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Excludes forecasted transaction for payment of variable interest on existing financial instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount, before tax and after reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Derivative instruments - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
Derivative instruments - Narrative (Details) - USD ($)	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Counterparty default losses recorded	$ 0
Gain or (loss) recognized in income on derivatives	1,000,000	$ 0	$ 1,000,000	$ 0
Value-at-risk methodology assumed holding period for instruments			1 day
Value-at-risk methodology confidence level percentage			99.00%
Additional collateral, aggregate fair value	99,000,000		$ 99,000,000		$ 76,000,000
Fair value hedging \| Securities – Available-for-sale
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Interest rate swaps designated as portfolio layer method fair value hedges of loans	17,400,000,000		17,400,000,000		15,100,000,000
Fair value hedging \| Securities – Available-for-sale \| Designated as hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Interest rate swaps designated as portfolio layer method fair value hedges of loans	11,900,000,000		11,900,000,000		8,900,000,000
Fair value hedging \| Loans
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Interest rate swaps designated as portfolio layer method fair value hedges of loans	2,800,000,000		2,800,000,000		2,900,000,000
Fair value hedging \| Loans \| Designated as hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Interest rate swaps designated as portfolio layer method fair value hedges of loans	1,400,000,000		$ 1,400,000,000		1,400,000,000
Interest rate swap
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Forecasted hedge period (less than)			3 years
Loss to be reclassified in next 12 months from AOCI to earnings			$ (10,000,000)
Interest rate swap \| Fair value hedging \| Loans
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Interest rate swaps designated as portfolio layer method fair value hedges of loans	1,400,000,000		1,400,000,000
Interest rate swap \| Cash flow hedges \| Loans
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Hedged financial instruments	2,600,000,000		2,600,000,000
Foreign exchange contracts \| Forecasted Foreign Currency
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Loss to be reclassified in next 12 months from AOCI to earnings			(9,000,000)
Foreign exchange contracts \| Designated as hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Hedged financial instruments, notional amount of derivative	12,288,000,000		12,288,000,000		$ 11,817,000,000
Foreign exchange contracts \| Cash flow hedges \| Forecasted Foreign Currency
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Hedged financial instruments, notional amount of derivative	771,000,000		771,000,000
Pre-tax loss recognized in OCI related to cash flow hedges			(9,000,000)
Foreign exchange contracts \| Net investment hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Hedged financial instruments, notional amount of derivative	11,500,000,000		11,500,000,000
Equity Swap \| Not Designated as Hedging Instrument, Economic Hedge
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Gain or (loss) recognized in income on derivatives	27,000,000	$ 15,000,000	20,000,000	$ 7,000,000
Balance Sheet Location [Axis]: us-gaap:DebtSecuritiesAvailableForSaleExcludingAccruedInterest \| Interest rate swap
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Hedged financial instruments	59,800,000,000		59,800,000,000
Hedged financial instruments, notional amount of derivative	59,600,000,000		59,600,000,000
Balance Sheet Location [Axis]: us-gaap:LongTermDebt \| Interest rate swap
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Hedged financial instruments	29,200,000,000		29,200,000,000
Hedged financial instruments, notional amount of derivative	$ 29,200,000,000		$ 29,200,000,000