Securities (Details 2) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	$ 1,051,043	$ 718,367
Unrealized Losses, Less Than 12 Months	(90,193)	(10,925)
Fair Value, 12 Months or Longer	134,960	74,575
Unrealized Losses, 12 Months or Longer	(15,906)	(2,812)
Fair Value, Total	1,186,003	792,942
Unrealized Losses, Total	(106,099)	(13,737)
U.S. Treasury and U.S. government sponsored entities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	94,866	81,236
Unrealized Losses, Less Than 12 Months	(8,125)	(1,960)
Fair Value, 12 Months or Longer	9,753	8,271
Unrealized Losses, 12 Months or Longer	(994)	(378)
Fair Value, Total	104,619	89,507
Unrealized Losses, Total	(9,119)	(2,338)
State and political subdivisions
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	420,523	103,651
Unrealized Losses, Less Than 12 Months	(38,939)	(1,020)
Fair Value, 12 Months or Longer	14,420	10,020
Unrealized Losses, 12 Months or Longer	(2,294)	(185)
Fair Value, Total	434,943	113,671
Unrealized Losses, Total	(41,233)	(1,205)
Mortgage-backed securities - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	511,033	525,792
Unrealized Losses, Less Than 12 Months	(42,169)	(7,872)
Fair Value, 12 Months or Longer	110,117	55,569
Unrealized Losses, 12 Months or Longer	(12,548)	(2,222)
Fair Value, Total	621,150	581,361
Unrealized Losses, Total	(54,717)	(10,094)
Collateralized mortgage obligations - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	18,856	7,270
Unrealized Losses, Less Than 12 Months	(735)	(71)
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	18,856	7,270
Unrealized Losses, Total	(735)	(71)
Corporate bonds
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	1,009	418
Unrealized Losses, Less Than 12 Months	(38)	(2)
Fair Value, 12 Months or Longer	670	715
Unrealized Losses, 12 Months or Longer	(70)	(27)
Fair Value, Total	1,679	1,133
Unrealized Losses, Total	(108)	$ (29)
Small Business Administration
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	4,756
Unrealized Losses, Less Than 12 Months	(187)
Fair Value, 12 Months or Longer	0
Unrealized Losses, 12 Months or Longer	0
Fair Value, Total	4,756
Unrealized Losses, Total	$ (187)

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