Securities (Details 2) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	$ 542,026	$ 91,251
Unrealized Losses, Less Than 12 Months	(7,963)	(506)
Fair Value, 12 Months or Longer	5,662	0
Unrealized Losses, 12 Months or Longer	(85)	0
Fair Value, Total	547,688	91,251
Unrealized Losses, Total	(8,048)	(506)
U.S. Treasury and U.S. government sponsored entities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	84,849	8,153
Unrealized Losses, Less Than 12 Months	(1,479)	(54)
Fair Value, 12 Months or Longer	627	0
Unrealized Losses, 12 Months or Longer	(23)	0
Fair Value, Total	85,476	8,153
Unrealized Losses, Total	(1,502)	(54)
State and political subdivisions
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	64,442	19,205
Unrealized Losses, Less Than 12 Months	(562)	(204)
Fair Value, 12 Months or Longer	4,579	0
Unrealized Losses, 12 Months or Longer	(56)	0
Fair Value, Total	69,021	19,205
Unrealized Losses, Total	(618)	(204)
Mortgage-backed securities - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	390,783	63,401
Unrealized Losses, Less Than 12 Months	(5,909)	(243)
Fair Value, 12 Months or Longer	10	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	390,793	63,401
Unrealized Losses, Total	(5,909)	(243)
Collateralized mortgage obligations - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	1,419	294
Unrealized Losses, Less Than 12 Months	(2)	(3)
Fair Value, 12 Months or Longer	249	0
Unrealized Losses, 12 Months or Longer	(3)	0
Fair Value, Total	1,668	294
Unrealized Losses, Total	(5)	(3)
Corporate bonds
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	533	198
Unrealized Losses, Less Than 12 Months	(11)	(2)
Fair Value, 12 Months or Longer	197	0
Unrealized Losses, 12 Months or Longer	(3)	0
Fair Value, Total	730	198
Unrealized Losses, Total	$ (14)	$ (2)