LOANS AND CREDIT QUALITY - Loans Held for Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Loans held for investment
Total LHFI	$ 6,231,796	$ 7,422,904
ACL	(38,743)	(40,500)	$ (41,500)
Total LHFI less ACL	6,193,053	7,382,404
Fair Value, Recurring
Loans held for investment
Single family LHFI	1,287	1,280
Commercial and industrial loans
Loans held for investment
Total LHFI	4,710,166	5,898,324
Commercial and industrial loans \| Real Estate Sector
Loans held for investment
Total LHFI	4,036,165	5,147,990
ACL	(24,484)	(27,912)	(27,859)
Commercial and industrial loans \| Commercial and Industrial Sector
Loans held for investment
Total LHFI	674,001	750,334
ACL	(7,462)	(3,849)	(4,277)
Commercial and industrial loans \| Non-owner occupied CRE
Loans held for investment
Total LHFI	570,750	641,885
ACL	(1,739)	(2,610)	(2,102)
Commercial and industrial loans \| Multifamily
Loans held for investment
Total LHFI	2,992,675	3,940,189
ACL	(14,909)	(13,093)	(10,974)
Commercial and industrial loans \| Construction/land development
Loans held for investment
Total LHFI	472,740	565,916
Commercial and industrial loans \| Owner occupied CRE
Loans held for investment
Total LHFI	361,997	391,285
ACL	(576)	(899)	(1,030)
Commercial and industrial loans \| Commercial business
Loans held for investment
Total LHFI	312,004	359,049
ACL	(6,886)	(2,950)	(3,247)
Consumer Portfolio Segment
Loans held for investment
Total LHFI	1,521,630	1,524,580
ACL	(6,797)	(8,739)	(9,364)
Consumer Portfolio Segment \| Single family
Loans held for investment
Total LHFI	1,109,095	1,140,279
ACL	(3,610)	(5,287)	(5,610)
Consumer Portfolio Segment \| Home equity and other
Loans held for investment
Total LHFI	412,535	384,301
ACL	$ (3,187)	$ (3,452)	$ (3,754)

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-Paragraph 3B
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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