ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY INFORMATION - Credit Quality Indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 11,702,372	$ 7,882,055	$ 8,011,699
Commercial | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	984,273	605,339
Year two, originated, fiscal year before current fiscal year	659,508	436,055
Year three, originated, two years before current fiscal year	481,236	386,061
Year four, originated, three years before current fiscal year	317,234	303,448
Year five, originated, four years before current fiscal year	193,991	159,343
Prior	274,274	171,029
Revolving loans amortized cost basis	7,700	5,580
Revolving loans converted to term	251,262	203,464
Total	3,169,478	2,270,319	2,228,514
Commercial | Commercial and industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	930,884	556,896
Year two, originated, fiscal year before current fiscal year	606,030	420,698
Year three, originated, two years before current fiscal year	464,829	329,354
Year four, originated, three years before current fiscal year	262,628	273,345
Year five, originated, four years before current fiscal year	149,437	139,800
Prior	263,633	148,809
Revolving loans amortized cost basis	7,690	5,551
Revolving loans converted to term	234,667	176,006
Total	2,919,798	2,050,459
Commercial | Commercial and industrial | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	24,704	35,910
Year two, originated, fiscal year before current fiscal year	36,492	949
Year three, originated, two years before current fiscal year	8,117	3,052
Year four, originated, three years before current fiscal year	10,012	1,057
Year five, originated, four years before current fiscal year	6,415	429
Prior	445	15,299
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	11,649	17,545
Total	97,834	74,241
Commercial | Commercial and industrial | Substandard or Lower
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	28,685	12,533
Year two, originated, fiscal year before current fiscal year	16,986	14,408
Year three, originated, two years before current fiscal year	8,290	53,655
Year four, originated, three years before current fiscal year	44,594	29,046
Year five, originated, four years before current fiscal year	38,139	19,114
Prior	10,196	6,921
Revolving loans amortized cost basis	10	29
Revolving loans converted to term	4,946	9,913
Total	151,846	145,619
Commercial | Owner-occupied commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	211,669	309,286
Year two, originated, fiscal year before current fiscal year	359,432	208,223
Year three, originated, two years before current fiscal year	292,988	179,202
Year four, originated, three years before current fiscal year	235,656	77,835
Year five, originated, four years before current fiscal year	125,993	142,277
Prior	404,152	280,687
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	158,701	144,197
Total	1,788,591	1,341,707	1,339,660
Commercial | Owner-occupied commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	210,160	305,156
Year two, originated, fiscal year before current fiscal year	353,951	189,128
Year three, originated, two years before current fiscal year	269,106	172,503
Year four, originated, three years before current fiscal year	233,159	67,526
Year five, originated, four years before current fiscal year	114,041	136,697
Prior	378,377	262,629
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	140,573	128,188
Total	1,699,367	1,261,827
Commercial | Owner-occupied commercial | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	537	938
Year two, originated, fiscal year before current fiscal year	0	5,359
Year three, originated, two years before current fiscal year	0	2,561
Year four, originated, three years before current fiscal year	0	891
Year five, originated, four years before current fiscal year	0	0
Prior	2,803	7,019
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	3,427	10,543
Total	6,767	27,311
Commercial | Owner-occupied commercial | Substandard or Lower
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	972	3,192
Year two, originated, fiscal year before current fiscal year	5,481	13,736
Year three, originated, two years before current fiscal year	23,882	4,138
Year four, originated, three years before current fiscal year	2,497	9,418
Year five, originated, four years before current fiscal year	11,952	5,580
Prior	22,972	11,039
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	14,701	5,466
Total	82,457	52,569
Commercial | Commercial mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	340,060	418,587
Year two, originated, fiscal year before current fiscal year	672,213	286,698
Year three, originated, two years before current fiscal year	548,477	221,100
Year four, originated, three years before current fiscal year	563,893	137,452
Year five, originated, four years before current fiscal year	255,223	243,705
Prior	693,660	383,997
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	206,853	189,971
Total	3,280,379	1,881,510	1,987,984
Commercial | Commercial mortgages | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	336,888	416,149
Year two, originated, fiscal year before current fiscal year	669,155	280,889
Year three, originated, two years before current fiscal year	529,554	217,311
Year four, originated, three years before current fiscal year	554,465	134,477
Year five, originated, four years before current fiscal year	251,605	229,863
Prior	650,400	368,527
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	202,570	187,396
Total	3,194,637	1,834,612
Commercial | Commercial mortgages | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	1,456	0
Year two, originated, fiscal year before current fiscal year	77	4,185
Year three, originated, two years before current fiscal year	6,077	0
Year four, originated, three years before current fiscal year	6,201	861
Year five, originated, four years before current fiscal year	0	11,588
Prior	32,197	1,385
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	3,706	2,097
Total	49,714	20,116
Commercial | Commercial mortgages | Substandard or Lower
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	1,716	2,438
Year two, originated, fiscal year before current fiscal year	2,981	1,624
Year three, originated, two years before current fiscal year	12,846	3,789
Year four, originated, three years before current fiscal year	3,227	2,114
Year five, originated, four years before current fiscal year	3,618	2,254
Prior	11,063	14,085
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	577	478
Total	36,028	26,782
Commercial | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	347,581	260,975
Year two, originated, fiscal year before current fiscal year	329,846	195,269
Year three, originated, two years before current fiscal year	176,120	87,290
Year four, originated, three years before current fiscal year	13,921	39,585
Year five, originated, four years before current fiscal year	26,587	2,313
Prior	3,915	11,297
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	130,233	90,484
Total	1,028,203	687,213	762,646
Commercial | Construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	345,581	248,053
Year two, originated, fiscal year before current fiscal year	324,841	195,269
Year three, originated, two years before current fiscal year	167,194	84,868
Year four, originated, three years before current fiscal year	13,731	39,585
Year five, originated, four years before current fiscal year	26,587	2,223
Prior	3,915	11,297
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	129,465	88,839
Total	1,011,314	670,134
Commercial | Construction | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0
Year two, originated, fiscal year before current fiscal year	603
Year three, originated, two years before current fiscal year	8,926
Year four, originated, three years before current fiscal year	0
Year five, originated, four years before current fiscal year	0
Prior	0
Revolving loans amortized cost basis	0
Revolving loans converted to term	0
Total	9,529
Commercial | Construction | Substandard or Lower
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	2,000	12,922
Year two, originated, fiscal year before current fiscal year	4,402	0
Year three, originated, two years before current fiscal year	0	2,422
Year four, originated, three years before current fiscal year	190	0
Year five, originated, four years before current fiscal year	0	90
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	768	1,645
Total	7,360	17,079
Commercial | PPP loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,200	31,500
Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	43,179	59,977
Year two, originated, fiscal year before current fiscal year	116,606	28,538
Year three, originated, two years before current fiscal year	61,610	13,570
Year four, originated, three years before current fiscal year	37,561	32,871
Year five, originated, four years before current fiscal year	45,346	45,032
Prior	454,291	362,745
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	0	0
Total	758,593	542,733	574,681
Residential | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	43,179	59,977
Year two, originated, fiscal year before current fiscal year	116,041	28,426
Year three, originated, two years before current fiscal year	61,107	12,526
Year four, originated, three years before current fiscal year	36,561	32,871
Year five, originated, four years before current fiscal year	45,222	44,969
Prior	450,032	358,964
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	0	0
Total	752,142	537,733
Residential | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	565	112
Year three, originated, two years before current fiscal year	503	1,044
Year four, originated, three years before current fiscal year	1,000	0
Year five, originated, four years before current fiscal year	124	63
Prior	4,259	3,781
Revolving loans amortized cost basis	0	0
Revolving loans converted to term	0	0
Total	6,451	5,000
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	416,706	219,918
Year two, originated, fiscal year before current fiscal year	206,914	170,069
Year three, originated, two years before current fiscal year	133,264	74,048
Year four, originated, three years before current fiscal year	57,333	204,119
Year five, originated, four years before current fiscal year	233,938	39,184
Prior	77,423	60,952
Revolving loans amortized cost basis	546,048	384,373
Revolving loans converted to term	5,502	5,910
Total	1,677,128	1,158,573	$ 1,118,214
Consumer | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	416,706	219,918
Year two, originated, fiscal year before current fiscal year	206,914	169,922
Year three, originated, two years before current fiscal year	133,026	74,048
Year four, originated, three years before current fiscal year	57,333	203,519
Year five, originated, four years before current fiscal year	233,399	39,113
Prior	77,423	60,952
Revolving loans amortized cost basis	544,810	382,718
Revolving loans converted to term	5,241	5,364
Total	1,674,852	1,155,554
Consumer | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	147
Year three, originated, two years before current fiscal year	238	0
Year four, originated, three years before current fiscal year	0	600
Year five, originated, four years before current fiscal year	539	71
Prior	0	0
Revolving loans amortized cost basis	1,238	1,655
Revolving loans converted to term	261	546
Total	$ 2,276	$ 3,019