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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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LOANS AND CREDIT QUALITY - Loan and Lease Receivable Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Loans held for investment
Total loan receivables before allowance for credit losses	$ 13,852,209	$ 14,176,936
Allowance for credit losses on loans	(156,796)	(153,319)	$ (75,515)	$ (88,558)
Net loan receivables	13,695,413	14,023,617
Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	33,447	34,686
Commercial and industrial
Loans held for investment
Total loan receivables before allowance for credit losses	460,081	482,170
Allowance for credit losses on loans	(8,860)	(8,417)	(4,297)	(4,869)
Commercial and industrial \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	8,490	8,024
Commercial real estate
Loans held for investment
Total loan receivables before allowance for credit losses	5,291,597	5,355,252
Allowance for credit losses on loans	(120,758)	(114,326)	(34,995)	(35,097)
Commercial real estate \| Multifamily
Loans held for investment
Total loan receivables before allowance for credit losses	5,291,597	5,355,252
Commercial real estate \| Multifamily \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	0	1,614
Commercial real estate \| Non-owner occupied
Loans held for investment
Total loan receivables before allowance for credit losses	1,711,611	1,740,277
Commercial real estate \| Non-owner occupied \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	11,586	11,586
Commercial real estate \| Owner occupied
Loans held for investment
Total loan receivables before allowance for credit losses	586,698	689,079
Commercial real estate \| Owner occupied \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	272	226
Commercial real estate \| Construction and land development
Loans held for investment
Total loan receivables before allowance for credit losses	399,546	493,992
Commercial real estate \| Construction and land development \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	3,225	2,962
Residential Real Estate
Loans held for investment
Total loan receivables before allowance for credit losses	4,017,120	3,970,803
Allowance for credit losses on loans	(13,621)	(13,294)	(4,763)	(4,656)
Residential Real Estate \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	7,459	7,187
Auto
Loans held for investment
Total loan receivables before allowance for credit losses	639,825	791,012
Allowance for credit losses on loans	(11,446)	(15,003)	(28,935)	(41,282)
Auto \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	2,412	3,086
Other consumer
Loans held for investment
Total loan receivables before allowance for credit losses	745,731	654,351
Allowance for credit losses on loans	(2,111)	(2,279)	$ (2,525)	$ (2,654)
Other consumer \| Greater than 89 Days Past Due
Loans held for investment
Total loan receivables before allowance for credit losses	$ 3	$ 1