LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loans by Risk Grade (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	$ 5,375,208	$ 5,989,264
Year two	4,780,511	2,709,114
Year three	2,408,007	1,925,433
Year four	1,521,426	1,037,226
Year five	788,555	898,344
Prior	2,199,180	1,925,757
Revolving Loans Amortized Cost Basis	1,733,969	1,389,120
Loans, net of unearned income	18,806,856	15,874,258
Commercial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	824,772	913,036
Year two	586,411	280,305
Year three	194,345	193,301
Year four	127,021	120,512
Year five	70,730	53,671
Prior	56,127	48,227
Revolving Loans Amortized Cost Basis	385,881	266,941
Loans, net of unearned income	2,245,287	1,875,993
Commercial, financial and agricultural | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	818,365	903,630
Year two	585,385	279,037
Year three	193,526	188,810
Year four	122,965	118,613
Year five	69,367	50,737
Prior	50,153	40,376
Revolving Loans Amortized Cost Basis	382,953	262,951
Loans, net of unearned income	2,222,714	1,844,154
Commercial, financial and agricultural | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	190
Year two	0	0
Year three	105	393
Year four	576	427
Year five	55	368
Prior	2,895	1,832
Revolving Loans Amortized Cost Basis	760	1,961
Loans, net of unearned income	4,391	5,171
Commercial, financial and agricultural | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	6,407	9,216
Year two	1,026	1,268
Year three	714	4,098
Year four	3,480	1,472
Year five	1,308	2,566
Prior	3,079	6,019
Revolving Loans Amortized Cost Basis	2,168	2,029
Loans, net of unearned income	18,182	26,668
Consumer installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	34,199	35,840
Year two	15,365	59,504
Year three	41,822	37,485
Year four	26,023	27,482
Year five	19,408	9,890
Prior	15,610	11,561
Revolving Loans Amortized Cost Basis	9,918	9,536
Loans, net of unearned income	162,345	191,298
Consumer installment | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	34,089	35,781
Year two	15,217	59,221
Year three	41,532	37,195
Year four	25,909	27,266
Year five	19,219	9,787
Prior	15,083	11,021
Revolving Loans Amortized Cost Basis	9,875	9,437
Loans, net of unearned income	160,924	189,708
Consumer installment | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	38	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	128	135
Revolving Loans Amortized Cost Basis	5	5
Loans, net of unearned income	171	140
Consumer installment | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	72	59
Year two	148	283
Year three	290	290
Year four	114	216
Year five	189	103
Prior	399	405
Revolving Loans Amortized Cost Basis	38	94
Loans, net of unearned income	1,250	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	13,608	102,227
Year five	61,006	90,688
Prior	62,569	52,533
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	137,183	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	13,565	101,969
Year five	60,812	90,294
Prior	61,749	51,468
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	136,126	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	15	19
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	15	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	43	234
Year five	194	384
Prior	805	1,046
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	1,042	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	980,342	787,837
Loans, net of unearned income	980,342	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	942,279	787,837
Loans, net of unearned income	942,279	787,837
Mortgage warehouse | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving Loans Amortized Cost Basis	18,895
Loans, net of unearned income	18,895
Mortgage warehouse | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving Loans Amortized Cost Basis	19,168
Loans, net of unearned income	19,168
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	17,385	44,727
Year two	46,009	219,385
Year three	188,438	14,831
Year four	9,820	5,494
Year five	4,605	109,040
Prior	250,540	179,224
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	516,797	572,701
Municipal | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	17,385	44,727
Year two	46,009	219,385
Year three	188,438	14,831
Year four	9,820	5,494
Year five	4,605	109,040
Prior	250,540	179,224
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	516,797	572,701
Premium finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,035,770	796,923
Year two	26,899	1,154
Year three	55	26
Year four	0	0
Year five	0	302
Prior	0	4
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	1,062,724	798,409
Premium finance | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,028,078	787,884
Year two	25,252	1,059
Year three	54	26
Year four	0	0
Year five	0	302
Prior	0	4
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	1,053,384	789,275
Premium finance | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	7,692	9,039
Year two	1,647	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	9,340	9,134
Real estate – construction and development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	674,559	833,764
Year two	818,827	292,041
Year three	308,182	176,483
Year four	128,263	53,509
Year five	22,383	24,590
Prior	26,935	47,626
Revolving Loans Amortized Cost Basis	30,577	24,326
Loans, net of unearned income	2,009,726	1,452,339
Real estate – construction and development | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	666,198	826,094
Year two	798,554	290,814
Year three	307,586	176,476
Year four	128,258	35,773
Year five	8,973	24,533
Prior	26,111	44,514
Revolving Loans Amortized Cost Basis	30,577	21,267
Loans, net of unearned income	1,966,257	1,419,471
Real estate – construction and development | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	8,341	6,527
Year two	19,987	549
Year three	432	0
Year four	0	15,260
Year five	174	0
Prior	189	2,101
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	29,123	24,437
Real estate – construction and development | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	20	1,143
Year two	286	678
Year three	164	7
Year four	5	2,476
Year five	13,236	57
Prior	635	1,011
Revolving Loans Amortized Cost Basis	0	3,059
Loans, net of unearned income	14,346	8,431
Real estate – commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,536,851	2,191,416
Year two	2,044,555	1,208,260
Year three	1,094,806	1,131,384
Year four	911,185	566,131
Year five	477,419	496,672
Prior	1,355,147	1,160,655
Revolving Loans Amortized Cost Basis	96,346	80,399
Loans, net of unearned income	7,516,309	6,834,917
Real estate – commercial and farmland | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,535,883	2,186,291
Year two	2,039,201	1,205,578
Year three	1,091,901	1,119,239
Year four	868,208	542,295
Year five	469,560	486,477
Prior	1,312,867	1,103,675
Revolving Loans Amortized Cost Basis	96,329	80,379
Loans, net of unearned income	7,413,949	6,723,934
Real estate – commercial and farmland | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	607	416
Year two	119	0
Year three	0	1,036
Year four	31,118	14,760
Year five	1,125	5,334
Prior	19,252	21,665
Revolving Loans Amortized Cost Basis	0	0
Loans, net of unearned income	52,221	43,211
Real estate – commercial and farmland | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	361	4,709
Year two	5,235	2,682
Year three	2,905	11,109
Year four	11,859	9,076
Year five	6,734	4,861
Prior	23,028	35,315
Revolving Loans Amortized Cost Basis	17	20
Loans, net of unearned income	50,139	67,772
Real estate – residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,251,672	1,173,558
Year two	1,242,445	648,465
Year three	580,359	351,592
Year four	305,506	161,871
Year five	133,004	113,491
Prior	432,252	425,927
Revolving Loans Amortized Cost Basis	230,905	220,081
Loans, net of unearned income	4,176,143	3,094,985
Real estate – residential | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,249,401	1,171,008
Year two	1,226,383	638,232
Year three	559,613	329,247
Year four	277,910	149,990
Year five	120,863	108,538
Prior	407,922	408,240
Revolving Loans Amortized Cost Basis	228,525	217,982
Loans, net of unearned income	4,070,617	3,023,237
Real estate – residential | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	447	145
Year two	147	66
Year three	94	1,106
Year four	693	505
Year five	369	356
Prior	3,419	3,717
Revolving Loans Amortized Cost Basis	422	49
Loans, net of unearned income	5,591	5,944
Real estate – residential | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1,824	2,405
Year two	15,915	10,167
Year three	20,652	21,239
Year four	26,903	11,376
Year five	11,772	4,597
Prior	20,911	13,970
Revolving Loans Amortized Cost Basis	1,958	2,050
Loans, net of unearned income	99,935	65,804
Total Loans | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	5,349,399	5,955,415
Year two	4,736,001	2,693,326
Year three	2,382,650	1,886,100
Year four	1,446,635	981,400
Year five	753,399	879,708
Prior	2,124,425	1,838,522
Revolving Loans Amortized Cost Basis	1,690,538	1,379,853
Loans, net of unearned income	18,483,047	15,614,324
Total Loans | 6
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	9,433	7,278
Year two	20,253	615
Year three	631	2,535
Year four	32,387	30,976
Year five	1,723	6,068
Prior	25,898	29,469
Revolving Loans Amortized Cost Basis	20,082	2,015
Loans, net of unearned income	110,407	78,956
Total Loans | 7
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	16,376	26,571
Year two	24,257	15,173
Year three	24,726	36,798
Year four	42,404	24,850
Year five	33,433	12,568
Prior	48,857	57,766
Revolving Loans Amortized Cost Basis	23,349	7,252
Loans, net of unearned income	$ 213,402	$ 180,978