LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	$ 205,677	$ 167,582
Provision for loan losses	49,376	(2,734)
Loans charged off	(14,956)	(8,579)
Recoveries of loans previously charged off	4,272	4,982
Ending balance, Allowance	242,658	161,251
Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	(1,711)
Commercial, financial and agricultural
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	39,455	26,829
Provision for loan losses	16,078	215
Loans charged off	(12,233)	(4,414)
Recoveries of loans previously charged off	2,043	2,896
Ending balance, Allowance	45,238	25,526
Commercial, financial and agricultural | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	(105)
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	5,413	6,097
Provision for loan losses	323	789
Loans charged off	(1,140)	(1,425)
Recoveries of loans previously charged off	297	158
Ending balance, Allowance	4,893	5,619
Consumer | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	0
Indirect automobile
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	174	476
Provision for loan losses	(219)	(290)
Loans charged off	(34)	(88)
Recoveries of loans previously charged off	216	275
Ending balance, Allowance	137	373
Indirect automobile | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	0
Mortgage warehouse
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	2,118	3,231
Provision for loan losses	(194)	(221)
Loans charged off	0	0
Recoveries of loans previously charged off	0	0
Ending balance, Allowance	1,924	3,010
Mortgage warehouse | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	0
Municipal
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	357	401
Provision for loan losses	(3)	(17)
Loans charged off	0	0
Recoveries of loans previously charged off	0	0
Ending balance, Allowance	354	384
Municipal | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	0
Premium finance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	1,025	2,729
Provision for loan losses	(93)	(92)
Loans charged off	(1,421)	(1,369)
Recoveries of loans previously charged off	1,382	1,247
Ending balance, Allowance	893	2,515
Premium finance | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	0
Real estate – construction and development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	32,659	22,045
Provision for loan losses	10,119	4,568
Loans charged off	0	0
Recoveries of loans previously charged off	100	218
Ending balance, Allowance	42,841	26,831
Real estate – construction and development | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	(37)
Real estate – commercial and farmland
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	67,433	77,831
Provision for loan losses	20,369	(9,552)
Loans charged off	0	(1,283)
Recoveries of loans previously charged off	44	37
Ending balance, Allowance	87,124	67,033
Real estate – commercial and farmland | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	(722)
Real estate – residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	57,043	27,943
Provision for loan losses	2,996	1,866
Loans charged off	(128)	0
Recoveries of loans previously charged off	190	151
Ending balance, Allowance	59,254	$ 29,960
Real estate – residential | Cumulative effect of change in accounting principle for ASU 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	$ (847)