LOANS AND ALLOWANCE FOR CREDIT LOSSES - Schedule of Activity in 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]
Balance at Beginning of Period	$ 574,358	$ 401,932	$ 569,520	$ 392,522
Charge-offs	(41,540)	(29,954)	(78,847)	(54,494)
Recoveries	9,293	3,426	14,584	6,350
Provision for Loan Losses	38,400	99,263	75,254	130,289
Balance at End of Period	580,511	565,109	580,511	565,109
Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	0	90,442	0	90,442
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	244,640	157,587	244,670	148,722
Charge-offs	(19,638)	(16,805)	(43,152)	(26,116)
Recoveries	6,670	973	10,061	2,253
Provision for Loan Losses	22,182	43,670	42,275	60,566
Balance at End of Period	253,854	215,917	253,854	215,917
Commercial \| Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	0	30,492	0	30,492
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	266,797	198,110	268,332	200,309
Charge-offs	(18,155)	(9,438)	(26,622)	(21,098)
Recoveries	1,018	123	1,426	393
Provision for Loan Losses	14,046	45,897	20,570	55,088
Balance at End of Period	263,706	294,303	263,706	294,303
Commercial real estate \| Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	0	59,611	0	59,611
BBCC
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	2,779	2,695	2,371	2,813
Charge-offs	(486)	(53)	(1,296)	(57)
Recoveries	118	99	240	399
Provision for Loan Losses	550	(253)	1,646	(667)
Balance at End of Period	2,961	2,488	2,961	2,488
BBCC \| Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	0	0	0	0
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	39,764	24,214	34,394	22,922
Charge-offs	(74)	(247)	(386)	(277)
Recoveries	59	150	124	238
Provision for Loan Losses	701	7,585	6,318	8,819
Balance at End of Period	40,450	31,850	40,450	31,850
Residential real estate \| Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	0	148	0	148
Indirect
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	8,309	9,063	8,021	8,434
Charge-offs	(1,395)	(1,766)	(3,207)	(3,700)
Recoveries	661	905	1,338	1,344
Provision for Loan Losses	(347)	222	1,076	2,346
Balance at End of Period	7,228	8,430	7,228	8,430
Indirect \| Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	0	6	0	6
Direct
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	2,412	2,053	2,478	2,304
Charge-offs	(1,735)	(1,480)	(4,026)	(3,081)
Recoveries	689	701	1,196	1,213
Provision for Loan Losses	907	1,243	2,625	2,081
Balance at End of Period	2,273	2,564	2,273	2,564
Direct \| Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	0	47	0	47
Home equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	9,657	8,210	9,254	7,018
Charge-offs	(57)	(165)	(158)	(165)
Recoveries	78	475	199	510
Provision for Loan Losses	361	899	744	2,056
Balance at End of Period	10,039	9,557	10,039	9,557
Home equity \| Allowance Established for Acquired PCD Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance Established for Acquired PCD Loans	$ 0	$ 138	$ 0	$ 138

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

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- Definition

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

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

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

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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