Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Investment securities available-for-sale
Amortized Cost	$ 867,143	$ 860,258
Unrealized Gains	32	5,362
Unrealized Losses	(138,065)	(11,971)
Fair Value	729,110	853,649
Amortized Cost	326,410	352,061
Unrealized Gains		1,110
Unrealized Losses	(53,104)	(3,494)
Fair Value	273,306	349,677
Amortized Cost	1,193,553	1,212,319
Unrealized Gains	32	6,472
Unrealized Losses	(191,169)	(15,465)
Fair Value	1,002,416	1,203,326
U. S. Treasury and agencies
Investment securities available-for-sale
Amortized Cost	3,826	5,028
Unrealized Gains	26	75
Unrealized Losses	(19)
Fair Value	3,833	5,103
Mortgage backed securities - Residential agency
Investment securities available-for-sale
Amortized Cost	721,170	717,781
Unrealized Gains	6	1,213
Unrealized Losses	(124,187)	(11,837)
Fair Value	596,989	707,157
Amortized Cost	187,746	207,518
Unrealized Losses	(34,268)	(3,145)
Fair Value	153,478	204,373
Mortgage backed securities - Commercial
Investment securities available-for-sale
Amortized Cost	72,584	88,362
Unrealized Gains		2,674
Unrealized Losses	(7,301)	(123)
Fair Value	65,283	90,913
Asset backed securities
Investment securities available-for-sale
Amortized Cost	35	52
Unrealized Gains		2
Fair Value	35	54
Corporate bonds
Investment securities available-for-sale
Amortized Cost	69,528	49,035
Unrealized Gains		1,398
Unrealized Losses	(6,558)	(11)
Fair Value	62,970	50,422
Obligations of state and political agencies.
Investment securities available-for-sale
Amortized Cost	138,664	144,543
Unrealized Gains		1,110
Unrealized Losses	(18,836)	(349)
Fair Value	$ 119,828	$ 145,304

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