Securities - Securities Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
The amortized cost and estimated fair value of securities with gross unrealized gains and losses
Amortized Cost	$ 283,216	$ 255,715
Gross Unrealized Gains	7,711	1,448
Gross Unrealized Losses	(1,050)	(3,785)
Fair Value	289,877	253,378
U.S. Treasury Securities
The amortized cost and estimated fair value of securities with gross unrealized gains and losses
Amortized Cost	4,990	17,862
Gross Unrealized Gains	8	54
Gross Unrealized Losses		(19)
Fair Value	4,998	17,897
Municipal Bonds
The amortized cost and estimated fair value of securities with gross unrealized gains and losses
Amortized Cost	99,441	117,991
Gross Unrealized Gains	6,338	1,257
Gross Unrealized Losses	(36)	(1,115)
Fair Value	105,743	118,133
Mortgage-Backed Securities
The amortized cost and estimated fair value of securities with gross unrealized gains and losses
Amortized Cost	64,312	48,816
Gross Unrealized Gains	697	52
Gross Unrealized Losses	(281)	(1,692)
Fair Value	64,728	47,176
Corporate Securities
The amortized cost and estimated fair value of securities with gross unrealized gains and losses
Amortized Cost	49,674	21,170
Gross Unrealized Gains	633	72
Gross Unrealized Losses	(131)	(124)
Fair Value	50,176	21,118
SBA Securities
The amortized cost and estimated fair value of securities with gross unrealized gains and losses
Amortized Cost	50,126	49,876
Gross Unrealized Gains	35	13
Gross Unrealized Losses	(602)	(835)
Fair Value	49,559	$ 49,054
Asset-Backed Securities
The amortized cost and estimated fair value of securities with gross unrealized gains and losses
Amortized Cost	14,673
Fair Value	$ 14,673

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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Amount, before tax, of unrealized loss 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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Amount 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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