SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Millions		3 Months Ended
Feb. 10, 2023 USD ($) branch	Mar. 31, 2024 segment
Asset Acquisition [Line Items]
Number of reporting segments \| segment		1
California \| Three Branches Purchase
Asset Acquisition [Line Items]
Number of branches purchased \| branch	3
Deposit liabilities assumed	$ 376
Acquired receivables	21
Goodwill	12
Intangible assets acquired	$ 11

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Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Deposits

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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- Definition

Amount of increase in financing receivable from purchase. Excludes net investment in lease.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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