Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Investment securities available-for-sale
Amortized Cost	$ 814,405	$ 849,567
Unrealized Gains	12	21
Unrealized Losses	(136,963)	(132,264)
Fair Value	677,454	717,324
Amortized Cost	308,634	321,902
Unrealized Losses	(47,924)	(50,990)
Allowance for Credit Losses	218
Fair Value	260,710	270,912
Amortized Cost	1,123,039	1,171,469
Unrealized Gains	12	21
Unrealized Losses	(184,887)	(183,254)
Allowance for Credit Losses	218
Fair Value	938,164	988,236
Available-for-Sale accrued interest receivable	2,000	1,900
Held-to-Maturity accrued interest receivable	1,400	1,500
U. S. Treasury and agencies
Investment securities available-for-sale
Amortized Cost	2,915	3,518
Unrealized Gains	11	19
Unrealized Losses	(20)	(17)
Fair Value	2,906	3,520
Mortgage backed securities - Residential agency
Investment securities available-for-sale
Amortized Cost	673,586	705,845
Unrealized Gains	1	2
Unrealized Losses	(115,131)	(118,168)
Fair Value	558,456	587,679
Amortized Cost	177,618	184,115
Unrealized Losses	(32,477)	(33,254)
Allowance for Credit Losses	103
Fair Value	145,141	150,861
Mortgage backed securities - Commercial
Investment securities available-for-sale
Amortized Cost	68,379	70,669
Unrealized Losses	(7,470)	(7,111)
Fair Value	60,909	63,558
Asset backed securities
Investment securities available-for-sale
Amortized Cost	28	34
Fair Value	28	34
Corporate bonds
Investment securities available-for-sale
Amortized Cost	69,497	69,501
Unrealized Losses	(14,342)	(6,968)
Fair Value	55,155	62,533
Obligations of state and political agencies.
Investment securities available-for-sale
Amortized Cost	131,016	137,787
Unrealized Losses	(15,447)	(17,736)
Allowance for Credit Losses	115
Fair Value	$ 115,569	$ 120,051

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