Investment Securities - Available-for-Sale and Held-to-Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Schedule Of Investments [Line Items]
Available-for-sale, amortized cost	$ 92,837	$ 94,071
Available-for-sale, gross unrealized gains	2,047	540
Available-for-sale, gross unrealized losses	(226)	(595)
Investment securities available-for-sale, at fair value	94,658	94,016
Held-to-maturity, amortized cost	9,306	14,340
Held-to-maturity, gross unrealized gains	167	22
Held-to-maturity, gross unrealized losses	(4)	(56)
Held-to-maturity, estimated fair value	9,469	14,306
Residential Mortgage Backed Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, amortized cost	31,638	46,182
Available-for-sale, gross unrealized gains	1,009	372
Available-for-sale, gross unrealized losses	(13)	(209)
Investment securities available-for-sale, at fair value	32,634	46,345
Commercial Mortgage Backed Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, amortized cost	52,201	43,686
Available-for-sale, gross unrealized gains	858	73
Available-for-sale, gross unrealized losses	(212)	(386)
Investment securities available-for-sale, at fair value	52,847	43,373
Held-to-maturity, amortized cost	7,052	8,923
Held-to-maturity, gross unrealized gains	105	2
Held-to-maturity, gross unrealized losses	(4)	(46)
Held-to-maturity, estimated fair value	7,153	8,879
US States and Political Subdivisions Debt Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, amortized cost	6,211	4,123
Available-for-sale, gross unrealized gains	113	95
Available-for-sale, gross unrealized losses	(1)
Investment securities available-for-sale, at fair value	6,323	4,218
Held-to-maturity, amortized cost	1,049	1,093
Held-to-maturity, gross unrealized gains	24	15
Held-to-maturity, estimated fair value	1,073	1,108
Corporate Notes [Member]
Schedule Of Investments [Line Items]
Available-for-sale, amortized cost	2,706
Available-for-sale, gross unrealized gains	67
Investment securities available-for-sale, at fair value	2,773
US Treasury Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, amortized cost	81	80
Investment securities available-for-sale, at fair value	81	80
US Government Agencies Debt Securities [Member]
Schedule Of Investments [Line Items]
Held-to-maturity, amortized cost	1,205	4,324
Held-to-maturity, gross unrealized gains	38	5
Held-to-maturity, gross unrealized losses		(10)
Held-to-maturity, estimated fair value	$ 1,243	$ 4,319

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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