VARIABLE INTEREST ENTITIES - Low Income Housing Tax Credit Partnerships (Details) - Variable Interest Entity - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Affordable housing tax credit partnerships
Variable Interest Entity [Line Items]
Affordable housing tax credit investments	$ 3,880		$ 3,880		$ 3,628
Less: amortization	(1,411)		(1,411)		(1,246)
Net affordable housing tax credit investments	2,469		2,469		2,382
Unfunded commitments	1,017		1,017		$ 1,065
Tax credits and other tax benefits recognized	86	$ 78	259	$ 230
Proportional Amortization Method
Variable Interest Entity [Line Items]
Proportional amortization expense included in provision for income taxes	$ 68	$ 63	$ 209	$ 189

Amortization Method Qualified Affordable Housing Project Investments, Accumulated Amortization

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Gross Investment In Qualified Affordable Housing Projects

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Amount, before amortization expense, of income tax credit and other tax benefit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

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Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method.

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Amount of commitment and contingent commitment, including amount of delayed equity contribution, for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, commitment and contingent commitment related to investment under tax credit program not meeting condition for accounting under proportional amortization method.

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