LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loans by Risk Grade (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	$ 3,623,824	$ 5,989,264
Year two	5,025,261	2,709,114
Year three	2,511,814	1,925,433
Year four	1,588,879	1,037,226
Year five	855,368	898,344
Prior	2,348,000	1,925,757
Revolving Loans Amortized Cost Basis	1,607,876	1,389,120
Loans, net of unearned income	17,561,022	15,874,258
9
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	0	0
Commercial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	534,488	913,036
Year two	638,418	280,305
Year three	215,471	193,301
Year four	147,175	120,512
Year five	86,618	53,671
Prior	66,680	48,227
Revolving Loans Amortized Cost Basis	333,995	266,941
Loans, net of unearned income	2,022,845	1,875,993
Commercial, financial and agricultural | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	527,870	903,630
Year two	637,107	279,037
Year three	214,934	188,810
Year four	143,779	118,613
Year five	85,058	50,737
Prior	59,648	40,376
Revolving Loans Amortized Cost Basis	331,032	262,951
Loans, net of unearned income	1,999,428	1,844,154
Commercial, financial and agricultural | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	190
Year two	151	0
Year three	92	393
Year four	274	427
Year five	160	368
Prior	2,881	1,832
Revolving Loans Amortized Cost Basis	794	1,961
Loans, net of unearned income	4,352	5,171
Commercial, financial and agricultural | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	6,618	9,216
Year two	1,160	1,268
Year three	445	4,098
Year four	3,122	1,472
Year five	1,400	2,566
Prior	4,151	6,019
Revolving Loans Amortized Cost Basis	2,169	2,029
Loans, net of unearned income	19,065	26,668
Consumer installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	25,944	35,840
Year two	18,234	59,504
Year three	46,455	37,485
Year four	28,923	27,482
Year five	21,619	9,890
Prior	17,167	11,561
Revolving Loans Amortized Cost Basis	8,895	9,536
Loans, net of unearned income	167,237	191,298
Consumer installment | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	25,920	35,781
Year two	18,153	59,221
Year three	46,134	37,195
Year four	28,754	27,266
Year five	21,530	9,787
Prior	16,607	11,021
Revolving Loans Amortized Cost Basis	8,804	9,437
Loans, net of unearned income	165,902	189,708
Consumer installment | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	130	135
Revolving Loans Amortized Cost Basis	5	5
Loans, net of unearned income	135	140
Consumer installment | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	24	59
Year two	81	283
Year three	321	290
Year four	169	216
Year five	89	103
Prior	430	405
Revolving Loans Amortized Cost Basis	86	94
Loans, net of unearned income	1,200	1,450
Indirect automobile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	20,331
Year four	15,400	102,227
Year five	73,223	90,688
Prior	83,622	52,533
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	172,245	265,779
Indirect automobile | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	20,276
Year four	15,350	101,969
Year five	72,999	90,294
Prior	82,645	51,468
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	170,994	264,007
Indirect automobile | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	24
Year five	0	10
Prior	20	19
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	20	53
Indirect automobile | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	55
Year four	50	234
Year five	224	384
Prior	957	1,046
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	1,231	1,719
Mortgage warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	949,191	787,837
Loans, net of unearned income	949,191	787,837
Mortgage warehouse | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	949,191	787,837
Loans, net of unearned income	949,191	787,837
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	10,775	44,727
Year two	43,922	219,385
Year three	194,357	14,831
Year four	13,779	5,494
Year five	4,853	109,040
Prior	261,582	179,224
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	529,268	572,701
Municipal | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	10,775	44,727
Year two	43,922	219,385
Year three	194,357	14,831
Year four	13,779	5,494
Year five	4,853	109,040
Prior	261,582	179,224
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	529,268	572,701
Premium finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	792,621	796,923
Year two	149,550	1,154
Year three	111	26
Year four	0	0
Year five	0	302
Prior	75	4
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	942,357	798,409
Premium finance | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	790,855	787,884
Year two	146,821	1,059
Year three	110	26
Year four	0	0
Year five	0	302
Prior	75	4
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	937,861	789,275
Premium finance | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,766	9,039
Year two	2,729	95
Year three	1	0
Year four	0	0
Year five	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	4,496	9,134
Real estate – construction and development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	385,031	833,764
Year two	850,008	292,041
Year three	300,493	176,483
Year four	128,463	53,509
Year five	26,018	24,590
Prior	31,066	47,626
Revolving Loans Amortized Cost Basis	26,205	24,326
Loans, net of unearned income	1,747,284	1,452,339
Real estate – construction and development | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	380,485	826,094
Year two	844,549	290,814
Year three	299,850	176,476
Year four	128,437	35,773
Year five	12,891	24,533
Prior	30,227	44,514
Revolving Loans Amortized Cost Basis	26,205	21,267
Loans, net of unearned income	1,722,644	1,419,471
Real estate – construction and development | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	4,330	6,527
Year two	5,241	549
Year three	432	0
Year four	0	15,260
Year five	48	0
Prior	580	2,101
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	10,631	24,437
Real estate – construction and development | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	216	1,143
Year two	218	678
Year three	211	7
Year four	26	2,476
Year five	13,079	57
Prior	259	1,011
Revolving Loans Amortized Cost Basis	0	3,059
Loans, net of unearned income	14,009	8,431
Real estate – commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	994,400	2,191,416
Year two	2,072,283	1,208,260
Year three	1,153,101	1,131,384
Year four	934,700	566,131
Year five	504,851	496,672
Prior	1,423,699	1,160,655
Revolving Loans Amortized Cost Basis	72,983	80,399
Loans, net of unearned income	7,156,017	6,834,917
Real estate – commercial and farmland | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	993,793	2,186,291
Year two	2,069,024	1,205,578
Year three	1,150,513	1,119,239
Year four	891,580	542,295
Year five	496,721	486,477
Prior	1,373,284	1,103,675
Revolving Loans Amortized Cost Basis	72,965	80,379
Loans, net of unearned income	7,047,880	6,723,934
Real estate – commercial and farmland | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	607	416
Year two	0	0
Year three	0	1,036
Year four	29,343	14,760
Year five	1,163	5,334
Prior	18,007	21,665
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	49,120	43,211
Real estate – commercial and farmland | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	4,709
Year two	3,259	2,682
Year three	2,588	11,109
Year four	13,777	9,076
Year five	6,967	4,861
Prior	32,408	35,315
Revolving Loans Amortized Cost Basis	18	20
Loans, net of unearned income	59,017	67,772
Real estate – residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	880,565	1,173,558
Year two	1,252,846	648,465
Year three	601,826	351,592
Year four	320,439	161,871
Year five	138,186	113,491
Prior	464,109	425,927
Revolving Loans Amortized Cost Basis	216,607	220,081
Loans, net of unearned income	3,874,578	3,094,985
Real estate – residential | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	880,233	1,171,008
Year two	1,243,230	638,232
Year three	582,823	329,247
Year four	290,790	149,990
Year five	123,347	108,538
Prior	438,034	408,240
Revolving Loans Amortized Cost Basis	214,894	217,982
Loans, net of unearned income	3,773,351	3,023,237
Real estate – residential | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	64	145
Year two	218	66
Year three	47	1,106
Year four	608	505
Year five	508	356
Prior	2,680	3,717
Revolving Loans Amortized Cost Basis	61	49
Loans, net of unearned income	4,186	5,944
Real estate – residential | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	268	2,405
Year two	9,398	10,167
Year three	18,956	21,239
Year four	29,041	11,376
Year five	14,331	4,597
Prior	23,395	13,970
Revolving Loans Amortized Cost Basis	1,652	2,050
Loans, net of unearned income	97,041	65,804
Total Loans | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	3,609,931	5,955,415
Year two	5,002,806	2,693,326
Year three	2,488,721	1,886,100
Year four	1,512,469	981,400
Year five	817,399	879,708
Prior	2,262,102	1,838,522
Revolving Loans Amortized Cost Basis	1,603,091	1,379,853
Loans, net of unearned income	17,296,519	15,614,324
Total Loans | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	5,001	7,278
Year two	5,610	615
Year three	571	2,535
Year four	30,225	30,976
Year five	1,879	6,068
Prior	24,298	29,469
Revolving Loans Amortized Cost Basis	860	2,015
Loans, net of unearned income	68,444	78,956
Total Loans | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	8,892	26,571
Year two	16,845	15,173
Year three	22,522	36,798
Year four	46,185	24,850
Year five	36,090	12,568
Prior	61,600	57,766
Revolving Loans Amortized Cost Basis	3,925	7,252
Loans, net of unearned income	$ 196,059	$ 180,978