MORTGAGE LOAN SALES AND SERVICING RIGHTS - Residential Mortgage Portfolio, MSRs Fair Value Method (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value, beginning of period			$ 593
Change in fair value during the period due to:
Fair value, end of period	$ 837		837
Residential mortgage
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value, beginning of period	752	$ 567	593	$ 573
Servicing assets obtained in acquisition	0	0	140	0
New servicing assets created	35	27	103	67
Change in fair value during the period due to:
Time decay	(8)	(6)	(24)	(20)
Payoffs	(14)	(11)	(43)	(28)
Changes in valuation inputs or assumptions	72	(1)	68	(16)
Fair value, end of period	837	576	837	576
Related loans serviced for third parties, unpaid principal balance, end of period	$ 43,861	$ 34,370	$ 43,861	$ 34,370

Servicing Asset At Fair Value Payoffs.

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- Definition

Time decay.

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No definition available.

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- Definition

Unpaid Principal Balance Of Third Party Serviced Loans

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No definition available.

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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of increase (decrease) in fair value from changes in the inputs, assumptions, or model used to calculate the fair value of the contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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Amount of increase (decrease) in fair value from changes classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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