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BUSINESS COMBINATION - Summary of Amount of Expenses Related to Merger (Details) - Mechanics Bank Acquisition - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Business Combination [Line Items]
Expenses related to the Merger	$ 4,794	$ 350
Severance and employee related
Business Combination [Line Items]
Expenses related to the Merger	1,628	0
Legal and professional
Business Combination [Line Items]
Expenses related to the Merger	2,865	350
System conversion, integration and other
Business Combination [Line Items]
Expenses related to the Merger	$ 301	$ 0

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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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