Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Investment securities available-for-sale
Amortized Cost	$ 799,043	$ 578,138
Unrealized Gains	8,218	14,749
Unrealized Losses	(12,164)	(545)
Fair Value	795,097	592,342
U. S. Treasury and agencies
Investment securities available-for-sale
Amortized Cost	5,704	5,926
Unrealized Losses	(21)	(19)
Fair Value	5,683	5,907
Obligations of state and political agencies
Investment securities available-for-sale
Amortized Cost	147,926	148,491
Unrealized Gains	2,710	5,282
Unrealized Losses	(1,445)
Fair Value	149,191	153,773
Mortgage backed securities - Residential agency
Investment securities available-for-sale
Amortized Cost	529,717	303,760
Unrealized Gains	2,146	3,395
Unrealized Losses	(10,268)	(436)
Fair Value	521,595	306,719
Mortgage backed securities - Commercial
Investment securities available-for-sale
Amortized Cost	85,060	89,300
Unrealized Gains	2,650	5,678
Unrealized Losses	(13)
Fair Value	87,697	94,978
Asset backed securities
Investment securities available-for-sale
Amortized Cost	91	109
Unrealized Gains	5	6
Fair Value	96	115
Corporate bonds
Investment securities available-for-sale
Amortized Cost	30,545	30,552
Unrealized Gains	707	388
Unrealized Losses	(417)	(90)
Fair Value	$ 30,835	$ 30,850

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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