FAIR VALUE - Schedule of Fair Value, Assets Measured on Nonrecurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 185	$ 82
Loans - collateral dependent loans	137,941	134,872
Level 1 \| Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	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]
Loans held for sale	70	55
Loans - collateral dependent loans	1,491	1,463
Level 3 \| Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	115	27
Loans - collateral dependent loans	136,450	133,409
Fair Value, Nonrecurring \| Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	23	13
Loans - collateral dependent loans	212	388
Other real estate owned	66	16
Fair Value Measurements	301	417
Fair Value, Nonrecurring \| Changes Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	(7)	(7)
Loans - collateral dependent loans	(55)	(171)
Other real estate owned	(8)	6
Fair Value Measurements	(70)	(172)
Fair Value, Nonrecurring \| Level 1 \| Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	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]
Loans held for sale	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]
Loans held for sale	23	13
Loans - collateral dependent loans	212	388
Other real estate owned	66	16
Fair Value Measurements	$ 301	$ 417

Other Real Estate Owned, Fair Value Disclosure

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- Definition

Fair value portion of asset recognized for present right to economic benefit.

+ References

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+ References

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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