Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Investment securities available-for-sale
Amortized Cost	$ 893,525	$ 860,258
Unrealized Gains	223	5,362
Unrealized Losses	(94,951)	(11,971)
Fair Value	798,797	853,649
Amortized Cost	331,741	352,061
Unrealized Gains	2	1,110
Unrealized Losses	(37,794)	(3,494)
Fair Value	293,949	349,677
Amortized Cost	1,225,266	1,212,319
Unrealized Gains	225	6,472
Unrealized Losses	(132,745)	(15,465)
Fair Value	1,092,746	1,203,326
U. S. Treasury and agencies
Investment securities available-for-sale
Amortized Cost	3,643	5,028
Unrealized Gains	66	75
Fair Value	3,709	5,103
Obligations of state and political agencies.
Investment securities available-for-sale
Amortized Cost	139,102	144,543
Unrealized Gains	2	1,110
Unrealized Losses	(12,927)	(349)
Fair Value	126,177	145,304
Mortgage backed securities - Residential agency
Investment securities available-for-sale
Amortized Cost	740,734	717,781
Unrealized Gains	27	1,213
Unrealized Losses	(88,254)	(11,837)
Fair Value	652,507	707,157
Amortized Cost	192,639	207,518
Unrealized Losses	(24,867)	(3,145)
Fair Value	167,772	204,373
Mortgage backed securities - Commercial
Investment securities available-for-sale
Amortized Cost	80,077	88,362
Unrealized Gains		2,674
Unrealized Losses	(3,947)	(123)
Fair Value	76,130	90,913
Asset backed securities
Investment securities available-for-sale
Amortized Cost	40	52
Unrealized Gains		2
Fair Value	40	54
Corporate bonds
Investment securities available-for-sale
Amortized Cost	69,031	49,035
Unrealized Gains	130	1,398
Unrealized Losses	(2,750)	(11)
Fair Value	$ 66,411	$ 50,422

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