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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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