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FAIR VALUE - Schedule of Fair Value, Assets Measured on Nonrecurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	$ 799	$ 82
Loans - collateral dependent loans	145,362	134,872
Level 1 | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	0	0
Loans - collateral dependent loans	0	0
Level 2 | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	781	55
Loans - collateral dependent loans	1,580	1,463
Level 3 | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	18	27
Loans - collateral dependent loans	143,782	133,409
Fair Value, Nonrecurring | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	5	13
Loans - collateral dependent loans	186	388
Other real estate owned	104	16
Fair Value Measurements	295	417
Fair Value, Nonrecurring | Changes Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	(7)	(7)
Loans - collateral dependent loans	(157)	(171)
Other real estate owned	0	6
Fair Value Measurements	(164)	(172)
Fair Value, Nonrecurring | Level 1 | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	0	0
Loans - collateral dependent loans	0	0
Other real estate owned	0	0
Fair Value Measurements	0	0
Fair Value, Nonrecurring | Level 2 | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	0	0
Loans - collateral dependent loans	0	0
Other real estate owned	0	0
Fair Value Measurements	0	0
Fair Value, Nonrecurring | Level 3 | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - loans	5	13
Loans - collateral dependent loans	186	388
Other real estate owned	104	16
Fair Value Measurements	$ 295	$ 417

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