LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Changes in Allowance for Loan Losses by Loan Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 212,520	$ 192,031	$ 195,597	$ 192,757
Provision for credit losses - loans	33,000	5,600	37,900	9,800
CECL Day 1 PSL ACL - loans			15,212
CECL Day 1 PCD ACL - loans			7,067
Recoveries on loans	2,332	1,936	3,255	3,192
Loans charged off	(6,237)	(4,251)	(17,416)	(10,433)
Ending balance	241,615	195,316	241,615	195,316
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	106,894	99,982	104,435	94,757
Provision for credit losses - loans	31,220	(406)	38,384	8,748
CECL Day 1 PSL ACL - loans			2,293
CECL Day 1 PCD ACL - loans			2,488
Recoveries on loans	1,269	1,514	1,656	2,452
Loans charged off	(1,358)	(2,106)	(11,231)	(6,973)
Ending balance	138,025	98,984	138,025	98,984
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	56,721	46,336	45,541	51,099
Provision for credit losses - loans	1,772	(83)	4,346	(4,450)
CECL Day 1 PSL ACL - loans			5,357
CECL Day 1 PCD ACL - loans			3,368
Recoveries on loans	5	98	80	103
Loans charged off	(3,547)	(74)	(3,741)	(475)
Ending balance	54,951	46,277	54,951	46,277
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,346	11,541	5,470	9,784
Provision for credit losses - loans	(1,813)	(2,735)	(2,141)	(978)
CECL Day 1 PSL ACL - loans			562
CECL Day 1 PCD ACL - loans			641
Recoveries on loans	1	0	2	0
Loans charged off	0	(63)	0	(63)
Ending balance	4,534	8,743	4,534	8,743
Consumer & Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	42,559	34,172	40,151	37,117
Provision for credit losses - loans	1,821	8,824	(2,689)	6,480
CECL Day 1 PSL ACL - loans			7,000
CECL Day 1 PCD ACL - loans			570
Recoveries on loans	1,057	324	1,517	637
Loans charged off	(1,332)	(2,008)	(2,444)	(2,922)
Ending balance	$ 44,105	$ 41,312	$ 44,105	$ 41,312

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of increase in allowance for credit loss for financing receivable purchased with credit deterioration.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from purchase of loan. Excludes financing receivable purchased with credit deterioration, loan acquired through business combination or acquisition, and net investment in lease.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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