LOANS AND ALLOWANCE FOR CREDIT LOSSES - Schedule of Activity in Allowance for Loan Losses (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]
Balance at Beginning of Period	$ 580,511	$ 565,109	$ 569,520	$ 392,522
Allowance Established for Acquired PCD Loans		13,104		103,546
Charge-offs	(48,275)	(35,402)	(127,122)	(89,896)
Recoveries	14,185	5,364	28,769	11,714
Provision for Loan Losses	33,237	24,003	108,491	154,292
Balance at End of Period	579,658	572,178	579,658	572,178
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	253,854	215,917	244,670	148,722
Realignment of Loan Portfolio Segments	1,999		1,999
Allowance Established for Acquired PCD Loans		6,666		37,158
Charge-offs	(41,827)	(22,068)	(84,979)	(48,185)
Recoveries	10,050	1,222	20,111	3,477
Provision for Loan Losses	29,138	33,246	71,413	93,811
Balance at End of Period	253,214	234,983	253,214	234,983
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	263,706	294,303	268,332	200,309
Realignment of Loan Portfolio Segments	962		962
Allowance Established for Acquired PCD Loans		6,438		66,049
Charge-offs	(1,810)	(8,016)	(28,432)	(29,114)
Recoveries	2,844	2,101	4,270	2,494
Provision for Loan Losses	(24,646)	(11,999)	(4,076)	43,089
Balance at End of Period	241,056	282,827	241,056	282,827
BBCC
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	2,961	2,488	2,371	2,813
Realignment of Loan Portfolio Segments	(2,961)		(2,961)
Allowance Established for Acquired PCD Loans		0		0
Charge-offs	0	(419)	(1,296)	(476)
Recoveries	0	25	240	423
Provision for Loan Losses	0	364	1,646	(302)
Balance at End of Period	0	2,458	0	2,458
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	40,450	31,850	34,394	22,922
Realignment of Loan Portfolio Segments	580		580
Allowance Established for Acquired PCD Loans		0		148
Charge-offs	(72)	(25)	(458)	(302)
Recoveries	78	51	202	288
Provision for Loan Losses	13,567	(445)	19,885	8,375
Balance at End of Period	54,603	31,431	54,603	31,431
Indirect
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	7,228	8,430	8,021	8,434
Realignment of Loan Portfolio Segments	357		357
Allowance Established for Acquired PCD Loans		0		6
Charge-offs	(2,539)	(1,863)	(5,746)	(5,562)
Recoveries	584	690	1,922	2,033
Provision for Loan Losses	1,683	704	2,759	3,050
Balance at End of Period	7,313	7,961	7,313	7,961
Direct
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	2,273	2,564	2,478	2,304
Realignment of Loan Portfolio Segments	(2,273)		(2,273)
Allowance Established for Acquired PCD Loans		0		47
Charge-offs	0	(2,907)	(4,026)	(5,988)
Recoveries	0	648	1,196	1,862
Provision for Loan Losses	0	2,113	2,625	4,193
Balance at End of Period	0	2,418	0	2,418
Home equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	10,039	9,557	9,254	7,018
Realignment of Loan Portfolio Segments	0		0
Allowance Established for Acquired PCD Loans		0		138
Charge-offs	(120)	(104)	(278)	(269)
Recoveries	174	627	373	1,137
Provision for Loan Losses	9,751	20	10,495	2,076
Balance at End of Period	19,844	$ 10,100	19,844	$ 10,100
Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		0
Realignment of Loan Portfolio Segments	1,336		1,336
Charge-offs	(1,907)		(1,907)
Recoveries	455		455
Provision for Loan Losses	3,744		3,744
Balance at End of Period	$ 3,628		$ 3,628

Financing Receivable, Allowance for Credit Loss, Realignment Of Loan Portfolio Segments

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Financing Receivable, Credit Loss, Expense (Reversal), Excluding Held-to-Maturity Securities

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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