GOODWILL AND CORE DEPOSIT INTANGIBLES - Schedule of Changes in Core Deposit Intangibles (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Finite-lived Intangible Assets [Roll Forward]
Less: amortization for the period	$ 13	$ 15
Core Deposits
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period, net of accumulated amortization	195
Less: amortization for the period	13
Balance at end of period, net of accumulated amortization	$ 182

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

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+ Details