Investment Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands		Mar. 31, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities
Amortized Cost		$ 1,196,521	$ 1,300,719
Gross Unrealized Gains		1,164	1,104
Gross Unrealized Losses		(148,188)	(170,424)
Fair Value	[1]	1,049,497	1,131,399
U.S. Treasury and government agencies
Schedule of Available-for-sale Securities
Amortized Cost		61,584	158,473
Gross Unrealized Gains		0	0
Gross Unrealized Losses		(3,146)	(6,051)
Fair Value		58,438	152,422
U.S. government sponsored agencies
Schedule of Available-for-sale Securities
Amortized Cost		109,927	101,753
Gross Unrealized Gains		22	18
Gross Unrealized Losses		(11,638)	(13,656)
Fair Value		98,311	88,115
States and political subdivisions
Schedule of Available-for-sale Securities
Amortized Cost		254,523	261,612
Gross Unrealized Gains		32	12
Gross Unrealized Losses		(29,559)	(35,742)
Fair Value		224,996	225,882
Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized Cost		697,452	707,025
Gross Unrealized Gains		1,070	1,017
Gross Unrealized Losses		(93,252)	(103,389)
Fair Value		605,270	604,653
Commercial mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized Cost		62,256	61,091
Gross Unrealized Gains		0	0
Gross Unrealized Losses		(10,103)	(11,042)
Fair Value		52,153	50,049
Bank-issued trust preferred securities
Schedule of Available-for-sale Securities
Amortized Cost		10,779	10,765
Gross Unrealized Gains		40	57
Gross Unrealized Losses		(490)	(544)
Fair Value		$ 10,329	$ 10,278

[1]     Available-for-sale investment securities and held-to-maturity investment securities are presented net of allowance for credit losses of $0 and $241, respectively, at March 31, 2023 and December 31, 2022.