LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Changes in Allowance for Loan Losses by Loan Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 241,615	$ 195,316	$ 195,597	$ 192,757
Provision for credit losses - loans	3,300	4,300	41,200	14,100
CECL Day 1 PSL ACL - loans			15,212
CECL Day 1 PCD ACL - loans			7,067
Recoveries on loans	1,487	1,351	4,742	4,543
Loans charged off	(30,876)	(6,499)	(48,292)	(16,932)
Ending balance	215,526	194,468	215,526	194,468
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	138,025	98,984	104,435	94,757
Provision for credit losses - loans	7,644	3,632	46,028	12,380
CECL Day 1 PSL ACL - loans			2,293
CECL Day 1 PCD ACL - loans			2,488
Recoveries on loans	791	914	2,447	3,366
Loans charged off	(29,742)	(4,519)	(40,973)	(11,492)
Ending balance	116,718	99,011	116,718	99,011
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	54,951	46,277	45,541	51,099
Provision for credit losses - loans	(409)	1,252	3,937	(3,198)
CECL Day 1 PSL ACL - loans			5,357
CECL Day 1 PCD ACL - loans			3,368
Recoveries on loans	157	4	237	107
Loans charged off	(87)	(391)	(3,828)	(866)
Ending balance	54,612	47,142	54,612	47,142
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,534	8,743	5,470	9,784
Provision for credit losses - loans	(182)	(2,257)	(2,323)	(3,235)
CECL Day 1 PSL ACL - loans			562
CECL Day 1 PCD ACL - loans			641
Recoveries on loans	0	0	2	0
Loans charged off	0	0	0	(63)
Ending balance	4,352	6,486	4,352	6,486
Consumer & Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	44,105	41,312	40,151	37,117
Provision for credit losses - loans	(3,753)	1,673	(6,442)	8,153
CECL Day 1 PSL ACL - loans			7,000
CECL Day 1 PCD ACL - loans			570
Recoveries on loans	539	433	2,056	1,070
Loans charged off	(1,047)	(1,589)	(3,491)	(4,511)
Ending balance	$ 39,844	$ 41,829	$ 39,844	$ 41,829

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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