Securities (Details 2) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	$ 778,927	$ 718,367
Unrealized Losses, Less Than 12 Months	(164,404)	(10,925)
Fair Value, 12 Months or Longer	493,562	74,575
Unrealized Losses, 12 Months or Longer	(125,872)	(2,812)
Fair Value, Total	1,272,489	792,942
Unrealized Losses, Total	(290,276)	(13,737)
U.S. Treasury and U.S. government sponsored entities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	56,522	81,236
Unrealized Losses, Less Than 12 Months	(6,430)	(1,960)
Fair Value, 12 Months or Longer	71,294	8,271
Unrealized Losses, 12 Months or Longer	(15,303)	(378)
Fair Value, Total	127,816	89,507
Unrealized Losses, Total	(21,733)	(2,338)
State and political subdivisions
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	485,654	103,651
Unrealized Losses, Less Than 12 Months	(121,150)	(1,020)
Fair Value, 12 Months or Longer	42,427	10,020
Unrealized Losses, 12 Months or Longer	(16,378)	(185)
Fair Value, Total	528,081	113,671
Unrealized Losses, Total	(137,528)	(1,205)
Mortgage-backed securities - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	183,962	525,792
Unrealized Losses, Less Than 12 Months	(32,556)	(7,872)
Fair Value, 12 Months or Longer	375,623	55,569
Unrealized Losses, 12 Months or Longer	(93,570)	(2,222)
Fair Value, Total	559,585	581,361
Unrealized Losses, Total	(126,126)	(10,094)
Collateralized mortgage obligations - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	45,785	7,270
Unrealized Losses, Less Than 12 Months	(3,715)	(71)
Fair Value, 12 Months or Longer	3,427	0
Unrealized Losses, 12 Months or Longer	(463)	0
Fair Value, Total	49,212	7,270
Unrealized Losses, Total	(4,178)	(71)
Corporate bonds
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	3,292	418
Unrealized Losses, Less Than 12 Months	(145)	(2)
Fair Value, 12 Months or Longer	791	715
Unrealized Losses, 12 Months or Longer	(158)	(27)
Fair Value, Total	4,083	1,133
Unrealized Losses, Total	(303)	$ (29)
Small Business Administration
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	3,712
Unrealized Losses, Less Than 12 Months	(408)
Fair Value, 12 Months or Longer	0
Unrealized Losses, 12 Months or Longer	0
Fair Value, Total	3,712
Unrealized Losses, Total	$ (408)

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