LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance, Allowance	$ 272,071	$ 172,642	$ 205,677	$ 167,582
Provision for loan losses	30,095	17,469	123,114	27,962
Loans charged off	(19,488)	(9,272)	(55,114)	(24,704)
Recoveries of loans previously charged off	7,426	4,052	18,138	14,051
Ending balance, Allowance	290,104	184,891	290,104	184,891
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	50,789	25,658	39,455	26,829
Provision for loan losses	14,650	9,568	46,050	11,521
Loans charged off	(16,519)	(4,722)	(42,068)	(13,527)
Recoveries of loans previously charged off	4,745	2,201	10,333	7,882
Ending balance, Allowance	53,665	32,705	53,665	32,705
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	4,548	5,269	5,413	6,097
Provision for loan losses	310	(244)	2,146	1,102
Loans charged off	(948)	(1,228)	(4,140)	(3,790)
Recoveries of loans previously charged off	203	277	694	665
Ending balance, Allowance	4,113	4,074	4,113	4,074
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	98	291	174	476
Provision for loan losses	(149)	(288)	(567)	(884)
Loans charged off	(36)	(50)	(135)	(179)
Recoveries of loans previously charged off	158	276	599	816
Ending balance, Allowance	71	229	71	229
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	2,335	3,885	2,118	3,231
Provision for loan losses	(589)	(1,884)	(372)	(1,230)
Loans charged off	0	0	0	0
Recoveries of loans previously charged off	0	0	0	0
Ending balance, Allowance	1,746	2,001	1,746	2,001
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	371	357	401
Provision for loan losses	(9)	(9)	(9)	(39)
Loans charged off	0	0	0	0
Recoveries of loans previously charged off	0	0	0	0
Ending balance, Allowance	348	362	348	362
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	776	2,762	1,025	2,729
Provision for loan losses	183	(638)	141	(530)
Loans charged off	(1,951)	(1,205)	(5,220)	(3,640)
Recoveries of loans previously charged off	1,639	1,023	4,701	3,383
Ending balance, Allowance	647	1,942	647	1,942
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	54,589	23,232	32,659	22,045
Provision for loan losses	8,525	3,227	29,920	3,841
Loans charged off	0	0	0	0
Recoveries of loans previously charged off	74	96	646	669
Ending balance, Allowance	63,188	26,555	63,188	26,555
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	96,140	59,349	67,433	77,831
Provision for loan losses	5,453	(1,200)	38,097	(18,399)
Loans charged off	0	(2,014)	(3,320)	(3,378)
Recoveries of loans previously charged off	371	96	476	177
Ending balance, Allowance	101,964	56,231	101,964	56,231
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	62,439	51,825	57,043	27,943
Provision for loan losses	1,721	8,937	7,708	32,580
Loans charged off	(34)	(53)	(231)	(190)
Recoveries of loans previously charged off	236	83	689	459
Ending balance, Allowance	$ 64,362	$ 60,792	64,362	$ 60,792
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)