Securities Available for Sale (Details 3) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	$ 506,824	$ 718,367
Unrealized Losses, Less Than 12 Months	(80,411)	(10,925)
Fair Value, 12 Months or Longer	728,881	74,575
Unrealized Losses, 12 Months or Longer	(186,354)	(2,812)
Fair Value, Total	1,235,705	792,942
Unrealized Losses, Total	(266,765)	(13,737)
U.S. Treasury and U.S. government sponsored entities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	52,311	81,236
Unrealized Losses, Less Than 12 Months	(5,835)	(1,960)
Fair Value, 12 Months or Longer	75,685	8,271
Unrealized Losses, 12 Months or Longer	(15,781)	(378)
Fair Value, Total	127,996	89,507
Unrealized Losses, Total	(21,616)	(2,338)
State and political subdivisions
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	306,709	103,651
Unrealized Losses, Less Than 12 Months	(56,650)	(1,020)
Fair Value, 12 Months or Longer	191,584	10,020
Unrealized Losses, 12 Months or Longer	(65,241)	(185)
Fair Value, Total	498,293	113,671
Unrealized Losses, Total	(121,891)	(1,205)
Corporate bonds
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	2,893	418
Unrealized Losses, Less Than 12 Months	(122)	(2)
Fair Value, 12 Months or Longer	986	715
Unrealized Losses, 12 Months or Longer	(180)	(27)
Fair Value, Total	3,879	1,133
Unrealized Losses, Total	(302)	(29)
Mortgage-backed securities - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	101,476	525,792
Unrealized Losses, Less Than 12 Months	(13,545)	(7,872)
Fair Value, 12 Months or Longer	453,233	55,569
Unrealized Losses, 12 Months or Longer	(104,109)	(2,222)
Fair Value, Total	554,709	581,361
Unrealized Losses, Total	(117,654)	(10,094)
Collateralized mortgage obligations
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	42,140	7,270
Unrealized Losses, Less Than 12 Months	(4,137)	(71)
Fair Value, 12 Months or Longer	5,214	0
Unrealized Losses, 12 Months or Longer	(800)	0
Fair Value, Total	47,354	7,270
Unrealized Losses, Total	(4,937)	$ (71)
Small Business Administration
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	1,295
Unrealized Losses, Less Than 12 Months	(122)
Fair Value, 12 Months or Longer	2,179
Unrealized Losses, 12 Months or Longer	(243)
Fair Value, Total	3,474
Unrealized Losses, Total	$ (365)

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