LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowance for Loan Losses (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, Allowance	$ 354,682	$ 345,555	$ 348,141	$ 338,084
Provision for loan losses	15,894	3,110	33,789	19,629
Loans charged off	(16,616)	(14,226)	(34,143)	(29,610)
Recoveries of loans previously charged off	5,553	7,128	11,726	13,464
Ending balance, Allowance	359,513	341,567	359,513	341,567
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	89,931	82,621	88,242	87,242
Provision for loan losses	8,169	12,345	16,712	15,733
Loans charged off	(8,657)	(10,517)	(19,245)	(22,376)
Recoveries of loans previously charged off	3,117	4,536	6,851	8,386
Ending balance, Allowance	92,560	88,985	92,560	88,985
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	8,518	6,145	11,503	7,327
Provision for loan losses	1,404	1,090	2,708	553
Loans charged off	(4,042)	(913)	(8,857)	(1,853)
Recoveries of loans previously charged off	373	251	899	546
Ending balance, Allowance	6,253	6,573	6,253	6,573
Mortgage warehouse
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	2,506	1,824	2,356	2,262
Provision for loan losses	237	456	387	18
Loans charged off	0	0	0	0
Recoveries of loans previously charged off	0	0	0	0
Ending balance, Allowance	2,743	2,280	2,743	2,280
Municipal
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	55	57	57	58
Provision for loan losses	0	1	(2)	0
Loans charged off	0	0	0	0
Recoveries of loans previously charged off	0	0	0	0
Ending balance, Allowance	55	58	55	58
Premium finance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	1,761	682	892	736
Provision for loan losses	471	567	1,576	762
Loans charged off	(2,253)	(2,719)	(4,315)	(5,048)
Recoveries of loans previously charged off	2,003	2,253	3,829	4,333
Ending balance, Allowance	1,982	783	1,982	783
Real estate – construction and development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	54,229	69,086	52,432	60,421
Provision for loan losses	3,081	(21,785)	4,878	(13,124)
Loans charged off	0	0	0	0
Recoveries of loans previously charged off	2	5	2	9
Ending balance, Allowance	57,312	47,306	57,312	47,306
Real estate – commercial and farmland
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	127,498	118,392	128,454	118,377
Provision for loan losses	7,084	9,335	6,100	9,315
Loans charged off	(1,561)	0	(1,561)	0
Recoveries of loans previously charged off	24	67	52	102
Ending balance, Allowance	133,045	127,794	133,045	127,794
Real estate – residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	70,184	66,748	64,205	61,661
Provision for loan losses	(4,552)	1,101	1,430	6,372
Loans charged off	(103)	(77)	(165)	(333)
Recoveries of loans previously charged off	34	16	93	88
Ending balance, Allowance	$ 65,563	$ 67,788	$ 65,563	$ 67,788

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

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