LOANS AND ALLOWANCE FOR CREDIT LOSSES - Schedule of Nonaccrual Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost	$ 470,196	$ 521,245
Nonaccrual With No Related Allowance	39,917	67,312
Past Due 90 Days or More and Accruing	4,079	2,691
Commercial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost	206,067	172,713
Nonaccrual With No Related Allowance	5,971	9,665
Past Due 90 Days or More and Accruing	1,770	1,310
Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost	148,165	244,395
Nonaccrual With No Related Allowance	33,946	57,647
Past Due 90 Days or More and Accruing	2,087	0
BBCC
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost		2,994
Nonaccrual With No Related Allowance		0
Past Due 90 Days or More and Accruing		177
Residential real estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost	87,932	73,806
Nonaccrual With No Related Allowance	0	0
Past Due 90 Days or More and Accruing	99	599
Indirect
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost	5,738	5,802
Nonaccrual With No Related Allowance	0	0
Past Due 90 Days or More and Accruing	47	203
Direct
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost		4,331
Nonaccrual With No Related Allowance		0
Past Due 90 Days or More and Accruing		74
Home equity
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost	21,948	17,204
Nonaccrual With No Related Allowance	0	0
Past Due 90 Days or More and Accruing	0	$ 328
Other consumer
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Amortized Cost	346
Nonaccrual With No Related Allowance	0
Past Due 90 Days or More and Accruing	$ 76

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