Securities - Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available for Sale
Amortized Cost	$ 317,528	$ 268,984
Gross Unrealized Gains	1,008	133
Gross Unrealized Losses	(2,956)	(6,150)
Estimated Fair Value	315,580	262,967
Held to Maturity
Amortized Cost		43,503
Gross Unrealized Gains		83
Gross Unrealized Losses		(596)
Estimated Fair Value		42,990
Investment Securities
Available for Sale
Amortized Cost	149,457	110,826
Gross Unrealized Gains	197	121
Gross Unrealized Losses	(2,557)	(2,045)
Estimated Fair Value	147,097	108,902
Held to Maturity
Amortized Cost		12,221
Gross Unrealized Gains		43
Gross Unrealized Losses		(1)
Estimated Fair Value		12,263
Investment Securities \| Municipal bonds
Available for Sale
Amortized Cost	39,524	882
Gross Unrealized Gains	125	0
Gross Unrealized Losses	(367)	(13)
Estimated Fair Value	39,282	869
Held to Maturity
Amortized Cost		11,919
Gross Unrealized Gains		43
Gross Unrealized Losses		0
Estimated Fair Value		11,962
Investment Securities \| U.S. government agency issued asset-backed securities (ABS agency)
Available for Sale
Amortized Cost	29,796
Gross Unrealized Gains	0
Gross Unrealized Losses	(938)
Estimated Fair Value	28,858
Investment Securities \| Corporate issued asset-backed securities (ABS corporate)
Available for Sale
Amortized Cost	41,728	37,897
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(873)	(1,174)
Estimated Fair Value	40,855	36,723
Investment Securities \| ABS agency
Available for Sale
Amortized Cost		26,125
Gross Unrealized Gains		0
Gross Unrealized Losses		(373)
Estimated Fair Value		25,752
Investment Securities \| Corporate issued debt securities (Corporate debt)
Available for Sale
Amortized Cost	9,986	9,986
Gross Unrealized Gains	0	98
Gross Unrealized Losses	(343)	(196)
Estimated Fair Value	9,643	9,888
Investment Securities \| U.S. Small Business Administration securities (SBA)
Available for Sale
Amortized Cost	28,423	35,936
Gross Unrealized Gains	72	23
Gross Unrealized Losses	(36)	(289)
Estimated Fair Value	28,459	35,670
Held to Maturity
Amortized Cost		302
Gross Unrealized Gains		0
Gross Unrealized Losses		(1)
Estimated Fair Value		301
Mortgage-Backed Securities
Available for Sale
Amortized Cost	168,071	158,158
Gross Unrealized Gains	811	12
Gross Unrealized Losses	(399)	(4,105)
Estimated Fair Value	168,483	154,065
Held to Maturity
Estimated Fair Value		30,727
Mortgage-Backed Securities \| U.S. government agency issued mortgage-backed securities (MBS agency)
Available for Sale
Amortized Cost	159,697	147,205
Gross Unrealized Gains	811	12
Gross Unrealized Losses	(341)	(3,762)
Estimated Fair Value	160,167	143,455
Held to Maturity
Amortized Cost		31,282
Gross Unrealized Gains		40
Gross Unrealized Losses		(595)
Estimated Fair Value		30,727
Mortgage-Backed Securities \| Corporate issued mortgage-backed securities (MBS corporate)
Available for Sale
Amortized Cost	8,374	10,953
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(58)	(343)
Estimated Fair Value	$ 8,316	$ 10,610

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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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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