INVESTMENT SECURITIES - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	$ 441,334	$ 147,033
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(59,004)	(2,019)
Available-for-sale securities, Twelve Months or Longer, Fair Value	40,225	26,881
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(8,001)	(1,266)
Available-for-sale securities, Fair Value	481,559	173,914
Available-for-sale securities, Unrealized Loss	(67,005)	(3,285)
Allowance for credit losses on securities	0
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	123,396
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(15,164)
Held-to-maturity securities, 12 Months or Longer, Fair Value	57,015
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(10,910)
Held-to-maturity securities, Fair Value	180,411
Held-to-maturity securities, Unrealized Losses	(26,074)
Agency mortgage-backed securities.
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	281,226	47,769
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(42,158)	(388)
Available-for-sale securities, Twelve Months or Longer, Fair Value	7,027	10,583
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(1,244)	(356)
Available-for-sale securities, Fair Value	288,253	58,352
Available-for-sale securities, Unrealized Loss	(43,402)	(744)
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	59,095
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(8,249)
Held-to-maturity securities, 12 Months or Longer, Fair Value	7,852
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(2,104)
Held-to-maturity securities, Fair Value	66,947
Held-to-maturity securities, Unrealized Losses	(10,353)
Agency collateralized mortgage obligations
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	38,814	92,727
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(4,581)	(1,588)
Available-for-sale securities, Twelve Months or Longer, Fair Value	31,962	16,298
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(6,550)	(910)
Available-for-sale securities, Fair Value	70,776	109,025
Available-for-sale securities, Unrealized Loss	(11,131)	(2,498)
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	62,540
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(6,614)
Held-to-maturity securities, 12 Months or Longer, Fair Value	45,750
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(8,044)
Held-to-maturity securities, Fair Value	108,290
Held-to-maturity securities, Unrealized Losses	(14,658)
States and political subdivisions securities
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	59,847	6,537
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(5,564)	(43)
Available-for-sale securities, Twelve Months or Longer, Fair Value	1,236
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(207)
Available-for-sale securities, Fair Value	61,083	6,537
Available-for-sale securities, Unrealized Loss	(5,771)	$ (43)
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	1,761
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(301)
Held-to-maturity securities, 12 Months or Longer, Fair Value	3,413
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(762)
Held-to-maturity securities, Fair Value	5,174
Held-to-maturity securities, Unrealized Losses	(1,063)
Small Business Administration securities
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	61,447
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(6,701)
Available-for-sale securities, Fair Value	61,447
Available-for-sale securities, Unrealized Loss	$ (6,701)

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