Investments in Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	$ 121,173
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(14,278)
Held-to-maturity securities, 12 Months or Longer, Fair Value	56,592
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(10,452)
Held-to-maturity securities, Fair Value	177,765
Held-to-maturity securities, Unrealized Losses	(24,730)
Agency mortgage-backed securities.
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	221,562	$ 47,769
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(27,597)	(388)
Available-for-sale securities, Twelve Months or Longer, Fair Value	64,918	10,583
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(13,187)	(356)
Available-for-sale securities, Fair Value	286,480	58,352
Available-for-sale securities, Unrealized Loss	(40,784)	(744)
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	59,218
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(7,766)
Held-to-maturity securities, 12 Months or Longer, Fair Value	7,868
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(2,054)
Held-to-maturity securities, Fair Value	67,086
Held-to-maturity securities, Unrealized Losses	(9,820)
Agency collateralized mortgage obligations
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	28,537	92,727
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(3,262)	(1,588)
Available-for-sale securities, Twelve Months or Longer, Fair Value	40,642	16,298
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(8,469)	(910)
Available-for-sale securities, Fair Value	69,179	109,025
Available-for-sale securities, Unrealized Loss	(11,731)	(2,498)
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	61,055
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(6,411)
Held-to-maturity securities, 12 Months or Longer, Fair Value	44,178
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(7,718)
Held-to-maturity securities, Fair Value	105,233
Held-to-maturity securities, Unrealized Losses	(14,129)
States and political subdivisions securities
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	44,455	6,537
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(2,913)	(43)
Available-for-sale securities, Twelve Months or Longer, Fair Value	3,753
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(378)
Available-for-sale securities, Fair Value	48,208	6,537
Available-for-sale securities, Unrealized Loss	(3,291)	(43)
HELD-TO-MATURITY SECURITIES:
Held-to-maturity securities, Less than 12 Month, Fair Value	900
Held-to-maturity securities, Less than 12 Months, Unrealized Losses	(101)
Held-to-maturity securities, 12 Months or Longer, Fair Value	4,546
Held-to-maturity securities, 12 Months or Longer, Unrealized Losses	(680)
Held-to-maturity securities, Fair Value	5,446
Held-to-maturity securities, Unrealized Losses	(781)
Small Business Administration securities
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	60,473
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(5,224)
Available-for-sale securities, Twelve Months or Longer, Fair Value	7,667
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(1,711)
Available-for-sale securities, Fair Value	68,140
Available-for-sale securities, Unrealized Loss	(6,935)
Unrealized Losses and Estimated Fair Value
AVAILABLE-FOR-SALE SECURITIES:
Available-for-sale securities, Less than Twelve Months, Fair Value	355,027	147,033
Available-for-sale Securities, Less than 12 Months, Unrealized Loss	(38,996)	(2,019)
Available-for-sale securities, Twelve Months or Longer, Fair Value	116,980	26,881
Available-for-sale Securities,12 Months or Longer, Unrealized Loss	(23,745)	(1,266)
Available-for-sale securities, Fair Value	472,007	173,914
Available-for-sale securities, Unrealized Loss	$ (62,741)	$ (3,285)

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