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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
-SubTopic 20
-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	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Loans held for investment
Total loan and lease receivables before allowance for credit losses	$ 14,568,795		$ 9,643,497
Allowance for credit losses on loans and leases	(168,959)	$ (68,334)	(88,558)	$ (103,481)	$ (108,021)	$ (133,778)
Net loan and lease receivables	14,399,836		9,554,939
Commercial and industrial
Loans held for investment
Total loan and lease receivables before allowance for credit losses	547,311		410,040
Allowance for credit losses on loans and leases	(23,244)	(3,456)	(4,869)	(5,005)	(5,409)	(5,805)
Commercial real estate
Loans held for investment
Total loan and lease receivables before allowance for credit losses	5,448,374		2,794,581
Allowance for credit losses on loans and leases	(101,063)	(33,599)	(35,097)	(34,682)	(34,092)	(31,486)
Commercial real estate \| Multifamily
Loans held for investment
Total loan and lease receivables before allowance for credit losses	5,448,374		2,794,581
Commercial real estate \| Construction and land development
Loans held for investment
Total loan and lease receivables before allowance for credit losses	535,776		104,430
Commercial real estate \| Non-owner occupied
Loans held for investment
Total loan and lease receivables before allowance for credit losses	1,864,040		1,657,597
Commercial real estate \| Owner occupied
Loans held for investment
Total loan and lease receivables before allowance for credit losses	709,239		360,100
Residential Real Estate
Loans held for investment
Total loan and lease receivables before allowance for credit losses	3,907,101		2,280,963
Allowance for credit losses on loans and leases	(22,193)	(4,977)	(4,656)	(6,799)	(6,741)	(6,745)
Auto
Loans held for investment
Total loan and lease receivables before allowance for credit losses	954,615		1,596,935
Allowance for credit losses on loans and leases	(19,733)	(23,867)	(41,282)	(54,135)	(58,698)	(87,053)
Other consumer
Loans held for investment
Total loan and lease receivables before allowance for credit losses	602,339		438,851
Allowance for credit losses on loans and leases	$ (2,726)	$ (2,435)	$ (2,654)	$ (2,860)	$ (3,081)	$ (2,689)