LOANS AND ALLOWANCE FOR CREDIT LOSSES - Analysis of Past-Due Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Past Due [Line Items]
Total Loans	$ 20,706,644	$ 20,739,906
Loans 90 Days or More Past Due and Still Accruing	14,930	17,733
Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	215,121	244,978
Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	75,419	106,949
Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	34,678	31,540
Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	105,024	106,489
Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	20,491,523	20,494,928
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Loans	3,075,971	2,953,135
Loans 90 Days or More Past Due and Still Accruing	4,778	5,159
Commercial and industrial | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	31,743	31,057
Commercial and industrial | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	12,901	12,300
Commercial and industrial | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	6,429	5,908
Commercial and industrial | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	12,413	12,849
Commercial and industrial | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	3,044,228	2,922,078
Consumer
Financing Receivable, Past Due [Line Items]
Total Loans	213,902	221,735
Loans 90 Days or More Past Due and Still Accruing	0	0
Consumer | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	1,924	3,548
Consumer | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	1,124	2,672
Consumer | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	483	557
Consumer | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	317	319
Consumer | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	211,978	218,187
Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Total Loans	891,412	965,053
Loans 90 Days or More Past Due and Still Accruing	0	0
Mortgage warehouse | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Mortgage warehouse | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Mortgage warehouse | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Mortgage warehouse | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Mortgage warehouse | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	891,412	965,053
Municipal
Financing Receivable, Past Due [Line Items]
Total Loans	429,227	441,408
Loans 90 Days or More Past Due and Still Accruing	0	0
Municipal | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Municipal | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Municipal | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Municipal | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	0	0
Municipal | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	429,227	441,408
Premium finance
Financing Receivable, Past Due [Line Items]
Total Loans	1,176,309	1,155,614
Loans 90 Days or More Past Due and Still Accruing	10,152	12,485
Premium finance | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	28,523	33,868
Premium finance | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	12,085	15,068
Premium finance | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	6,286	6,315
Premium finance | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	10,152	12,485
Premium finance | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	1,147,786	1,121,746
Real estate – construction and development
Financing Receivable, Past Due [Line Items]
Total Loans	1,842,431	1,998,506
Loans 90 Days or More Past Due and Still Accruing	0	89
Real estate – construction and development | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	9,524	27,349
Real estate – construction and development | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	5,803	23,102
Real estate – construction and development | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	1,076	461
Real estate – construction and development | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	2,645	3,786
Real estate – construction and development | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	1,832,907	1,971,157
Real estate – commercial and farmland
Financing Receivable, Past Due [Line Items]
Total Loans	8,574,626	8,445,958
Loans 90 Days or More Past Due and Still Accruing	0	0
Real estate – commercial and farmland | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	15,015	15,202
Real estate – commercial and farmland | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	7,389	6,787
Real estate – commercial and farmland | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	973	2,435
Real estate – commercial and farmland | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	6,653	5,980
Real estate – commercial and farmland | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	8,559,611	8,430,756
Real estate – residential
Financing Receivable, Past Due [Line Items]
Total Loans	4,502,766	4,558,497
Loans 90 Days or More Past Due and Still Accruing	0	0
Real estate – residential | Total Loans Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	128,392	133,954
Real estate – residential | Loans 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	36,117	47,020
Real estate – residential | Loans 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	19,431	15,864
Real estate – residential | Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans	72,844	71,070
Real estate – residential | Current Loans
Financing Receivable, Past Due [Line Items]
Total Loans	$ 4,374,374	$ 4,424,543