Securities Available for Sale (Details 3) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	$ 49,846	$ 506,824
Unrealized Losses, Less Than 12 Months	(3,025)	(80,411)
Fair Value, 12 Months or Longer	1,116,642	728,881
Unrealized Losses, 12 Months or Longer	(219,539)	(186,354)
Fair Value, Total	1,166,488	1,235,705
Unrealized Losses, Total	(222,564)	(266,765)
U.S. Treasury and U.S. government sponsored entities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	399	52,311
Unrealized Losses, Less Than 12 Months	(1)	(5,835)
Fair Value, 12 Months or Longer	122,361	75,685
Unrealized Losses, 12 Months or Longer	(17,596)	(15,781)
Fair Value, Total	122,760	127,996
Unrealized Losses, Total	(17,597)	(21,616)
State and political subdivisions
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	15,852	306,709
Unrealized Losses, Less Than 12 Months	(1,684)	(56,650)
Fair Value, 12 Months or Longer	428,416	191,584
Unrealized Losses, 12 Months or Longer	(91,819)	(65,241)
Fair Value, Total	444,268	498,293
Unrealized Losses, Total	(93,503)	(121,891)
Corporate bonds
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	8,463	2,893
Unrealized Losses, Less Than 12 Months	(284)	(122)
Fair Value, 12 Months or Longer	3,881	986
Unrealized Losses, 12 Months or Longer	(182)	(180)
Fair Value, Total	12,344	3,879
Unrealized Losses, Total	(466)	(302)
Mortgage-backed securities - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	5,113	101,476
Unrealized Losses, Less Than 12 Months	(76)	(13,545)
Fair Value, 12 Months or Longer	515,259	453,233
Unrealized Losses, 12 Months or Longer	(104,068)	(104,109)
Fair Value, Total	520,372	554,709
Unrealized Losses, Total	(104,144)	(117,654)
Collateralized mortgage obligations
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	20,019	42,140
Unrealized Losses, Less Than 12 Months	(980)	(4,137)
Fair Value, 12 Months or Longer	43,808	5,214
Unrealized Losses, 12 Months or Longer	(5,579)	(800)
Fair Value, Total	63,827	47,354
Unrealized Losses, Total	(6,559)	(4,937)
Small Business Administration
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	0	1,295
Unrealized Losses, Less Than 12 Months	0	(122)
Fair Value, 12 Months or Longer	2,917	2,179
Unrealized Losses, 12 Months or Longer	(295)	(243)
Fair Value, Total	2,917	3,474
Unrealized Losses, Total	$ (295)	$ (365)

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