INVESTMENT SECURITIES (Investment Securities at an Unrealized Loss Position) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	$ 19,557	$ 240,949
Less Than 12 Months, Unrecognized Losses	(219)	(21,134)
12 Month or Longer, Fair Value	588,097	425,202
12 Month or Longer, Unrecognized Losses	(108,028)	(108,448)
Total Fair Value	607,654	666,151
Total Unrecognized Losses	108,247	129,582
Schedule of Held-to-Maturity Securities [Line Items]
Less Than 12 Months, Fair Value	8,853	596,780
Less Than 12 Months, Unrecognized Losses	(33)	(68,103)
12 Month or Longer, Fair Value	547,631	0
12 Month or Longer, Unrecognized Losses	(67,188)	0
Total Fair Value	556,484	596,780
Total Unrecognized Losses	(67,221)	(68,103)
States and political subdivisions
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	534	52,244
Less Than 12 Months, Unrecognized Losses	(1)	(4,807)
12 Month or Longer, Fair Value	114,601	78,389
12 Month or Longer, Unrecognized Losses	(29,809)	(31,874)
Total Fair Value	115,135	130,633
Total Unrecognized Losses	29,810	36,681
Schedule of Held-to-Maturity Securities [Line Items]
Less Than 12 Months, Fair Value	0	37,113
Less Than 12 Months, Unrecognized Losses	0	(4,727)
12 Month or Longer, Fair Value	35,253	0
12 Month or Longer, Unrecognized Losses	(6,706)	0
Total Fair Value	35,253	37,113
Total Unrecognized Losses	(6,706)	(4,727)
Corporate securities
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	0	0
Less Than 12 Months, Unrecognized Losses	0	0
12 Month or Longer, Fair Value	31,414	30,211
12 Month or Longer, Unrecognized Losses	(4,317)	(5,995)
Total Fair Value	31,414	30,211
Total Unrecognized Losses	4,317	5,995
U.S. Treasury obligations and direct obligations of U.S Government agencies
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	2,893	9,651
Less Than 12 Months, Unrecognized Losses	(87)	(245)
12 Month or Longer, Fair Value	16,286	15,541
12 Month or Longer, Unrecognized Losses	(1,854)	(2,072)
Total Fair Value	19,179	25,192
Total Unrecognized Losses	1,941	2,317
Residential - U.S. Government-sponsored enterprises
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	0	149,624
Less Than 12 Months, Unrecognized Losses	0	(13,990)
12 Month or Longer, Fair Value	367,887	274,179
12 Month or Longer, Unrecognized Losses	(63,607)	(61,196)
Total Fair Value	367,887	423,803
Total Unrecognized Losses	63,607	75,186
Schedule of Held-to-Maturity Securities [Line Items]
Less Than 12 Months, Fair Value	8,853	559,667
Less Than 12 Months, Unrecognized Losses	(33)	(63,376)
12 Month or Longer, Fair Value	512,378	0
12 Month or Longer, Unrecognized Losses	(60,482)	0
Total Fair Value	521,231	559,667
Total Unrecognized Losses	(60,515)	(63,376)
Residential - Non-government agencies
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	0	2,890
Less Than 12 Months, Unrecognized Losses	0	(334)
12 Month or Longer, Fair Value	8,169	5,772
12 Month or Longer, Unrecognized Losses	(980)	(833)
Total Fair Value	8,169	8,662
Total Unrecognized Losses	980	1,167
Commercial - Non-government agencies
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	6,467	25,034
Less Than 12 Months, Unrecognized Losses	(1)	(1,724)
12 Month or Longer, Fair Value	44,447	21,110
12 Month or Longer, Unrecognized Losses	(7,403)	(6,478)
Total Fair Value	50,914	46,144
Total Unrecognized Losses	7,404	8,202
Commercial - Non-government agencies
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, Fair Value	9,663	1,506
Less Than 12 Months, Unrecognized Losses	(130)	(34)
12 Month or Longer, Fair Value	5,293	0
12 Month or Longer, Unrecognized Losses	(58)	0
Total Fair Value	14,956	1,506
Total Unrecognized Losses	$ 188	$ 34