Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 61,000	$ 62,026
Held-to-maturity Securities, Unrealized Gains	231	184
Held-to-maturity Securities, Unrealized Losses	(325)	(1,075)
Held-to-maturity Securities, Estimated Fair Value	60,906	61,135
Available-for-sale Securities, Amortized Cost	88,434	98,765
Available-for-sale Securities, Unrealized Gains	6
Available-for-sale Securities, Unrealized Losses	(1,318)	(2,122)
Available-for-sale, Estimated Fair Value	87,122	96,643
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,817	8,749
Held-to-maturity Securities, Unrealized Gains	33	41
Held-to-maturity Securities, Estimated Fair Value	8,850	8,790
Available-for-sale Securities, Amortized Cost	38,088	48,082
Available-for-sale Securities, Unrealized Gains	3
Available-for-sale Securities, Unrealized Losses	(139)	(359)
Available-for-sale, Estimated Fair Value	37,952	47,723
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	369	389
Held-to-maturity Securities, Unrealized Gains	4
Held-to-maturity Securities, Estimated Fair Value	373	389
Available-for-sale Securities, Amortized Cost	27,591	27,563
Available-for-sale Securities, Unrealized Gains	3
Available-for-sale Securities, Unrealized Losses	(605)	(1,005)
Available-for-sale, Estimated Fair Value	26,989	26,558
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	13,759	13,851
Held-to-maturity Securities, Unrealized Gains	142	124
Held-to-maturity Securities, Unrealized Losses	(12)	(47)
Held-to-maturity Securities, Estimated Fair Value	13,889	13,928
Available-for-sale Securities, Amortized Cost	10,868	10,890
Available-for-sale Securities, Unrealized Losses	(126)	(186)
Available-for-sale, Estimated Fair Value	10,742	10,704
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,102	1,159
Held-to-maturity Securities, Unrealized Losses	(21)	(27)
Held-to-maturity Securities, Estimated Fair Value	1,081	1,132
Available-for-sale Securities, Amortized Cost	9,909	10,249
Available-for-sale Securities, Unrealized Losses	(363)	(441)
Available-for-sale, Estimated Fair Value	9,546	9,808
State and Municipal Taxable [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	362	362
Held-to-maturity Securities, Unrealized Losses	(1)	(3)
Held-to-maturity Securities, Estimated Fair Value	361	359
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	36,591	37,516
Held-to-maturity Securities, Unrealized Gains	52	19
Held-to-maturity Securities, Unrealized Losses	(291)	(998)
Held-to-maturity Securities, Estimated Fair Value	36,352	36,537
Available-for-sale Securities, Amortized Cost	1,978	1,981
Available-for-sale Securities, Unrealized Losses	(85)	(131)
Available-for-sale, Estimated Fair Value	$ 1,893	$ 1,850

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