Securities (Details 2) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	$ 1,134,370	$ 718,367
Unrealized Losses, Less Than 12 Months	(178,239)	(10,925)
Fair Value, 12 Months or Longer	157,643	74,575
Unrealized Losses, 12 Months or Longer	(28,901)	(2,812)
Fair Value, Total	1,292,013	792,942
Unrealized Losses, Total	(207,140)	(13,737)
U.S. Treasury and U.S. government sponsored entities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	71,491	81,236
Unrealized Losses, Less Than 12 Months	(9,691)	(1,960)
Fair Value, 12 Months or Longer	27,682	8,271
Unrealized Losses, 12 Months or Longer	(3,839)	(378)
Fair Value, Total	99,173	89,507
Unrealized Losses, Total	(13,530)	(2,338)
State and political subdivisions
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	507,354	103,651
Unrealized Losses, Less Than 12 Months	(95,392)	(1,020)
Fair Value, 12 Months or Longer	14,938	10,020
Unrealized Losses, 12 Months or Longer	(4,715)	(185)
Fair Value, Total	522,292	113,671
Unrealized Losses, Total	(100,107)	(1,205)
Mortgage-backed securities - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	497,183	525,792
Unrealized Losses, Less Than 12 Months	(70,416)	(7,872)
Fair Value, 12 Months or Longer	114,385	55,569
Unrealized Losses, 12 Months or Longer	(20,247)	(2,222)
Fair Value, Total	611,568	581,361
Unrealized Losses, Total	(90,663)	(10,094)
Collateralized mortgage obligations - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	50,712	7,270
Unrealized Losses, Less Than 12 Months	(2,388)	(71)
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	50,712	7,270
Unrealized Losses, Total	(2,388)	(71)
Corporate bonds
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	3,269	418
Unrealized Losses, Less Than 12 Months	(86)	(2)
Fair Value, 12 Months or Longer	638	715
Unrealized Losses, 12 Months or Longer	(100)	(27)
Fair Value, Total	3,907	1,133
Unrealized Losses, Total	(186)	$ (29)
Small Business Administration
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	4,361
Unrealized Losses, Less Than 12 Months	(266)
Fair Value, 12 Months or Longer	0
Unrealized Losses, 12 Months or Longer	0
Fair Value, Total	4,361
Unrealized Losses, Total	$ (266)

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