SECURITIES - Unrealized Loss Analysis on Available-for-Sale and Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities
Less than 12 months, fair value	$ 32,146	$ 455,318
12 months or more, fair value	939,071	686,704
Total fair value	971,217	1,142,022
Less than 12 months, unrealized losses	2,301	53,415
12 Months or more, unrealized losses	264,101	162,064
Total unrealized losses	266,402	215,479
U.S. Treasury securities
Schedule of Available-for-sale Securities
Less than 12 months, fair value	2,466	3,034
12 months or more, fair value	395	0
Total fair value	2,861	3,034
Less than 12 months, unrealized losses	8	23
12 Months or more, unrealized losses	4	0
Total unrealized losses	12	23
U.S. government sponsored agencies
Schedule of Available-for-sale Securities
Less than 12 months, fair value	0	8,420
12 months or more, fair value	115,671	118,541
Total fair value	115,671	126,961
Less than 12 months, unrealized losses	0	1,350
12 Months or more, unrealized losses	33,224	27,873
Total unrealized losses	33,224	29,223
Mortgage-backed securities: residential
Schedule of Available-for-sale Securities
Less than 12 months, fair value	3,596	165,897
12 months or more, fair value	425,212	323,727
Total fair value	428,808	489,624
Less than 12 months, unrealized losses	187	18,637
12 Months or more, unrealized losses	101,970	67,297
Total unrealized losses	102,157	85,934
State and municipal securities
Schedule of Available-for-sale Securities
Less than 12 months, fair value	26,084	277,967
12 months or more, fair value	397,793	244,436
Total fair value	423,877	522,403
Less than 12 months, unrealized losses	2,106	33,405
12 Months or more, unrealized losses	128,903	66,894
Total unrealized losses	$ 131,009	$ 100,299