Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 62,069	$ 62,390
Held-to-maturity Securities, Unrealized Gains	120	474
Held-to-maturity Securities, Unrealized Losses	(1,886)	(444)
Held-to-maturity Securities, Fair Value	60,303	62,420
Available-for-sale Securities, Amortized Cost	102,345	113,555
Available-for-sale Securities, Unrealized Gains		12
Available-for-sale Securities, Unrealized Losses	(3,184)	(1,784)
AFS investment securities	99,161	111,783
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,682	8,483
Held-to-maturity Securities, Unrealized Gains	34	163
Held-to-maturity Securities, Fair Value	8,716	8,646
Available-for-sale Securities, Amortized Cost	50,077	53,279
Available-for-sale Securities, Unrealized Losses	(622)	(386)
AFS investment securities	49,455	52,893
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	413	496
Held-to-maturity Securities, Unrealized Gains		9
Held-to-maturity Securities, Unrealized Losses	(4)
Held-to-maturity Securities, Fair Value	409	505
Available-for-sale Securities, Amortized Cost	28,762	33,203
Available-for-sale Securities, Unrealized Losses	(1,431)	(715)
AFS investment securities	27,331	32,488
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	13,882	14,047
Held-to-maturity Securities, Unrealized Gains	84	243
Held-to-maturity Securities, Unrealized Losses	(95)	(2)
Held-to-maturity Securities, Fair Value	13,871	14,288
Available-for-sale Securities, Amortized Cost	10,913	12,981
Available-for-sale Securities, Unrealized Gains		12
Available-for-sale Securities, Unrealized Losses	(275)	(173)
AFS investment securities	10,638	12,820
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,211	1,471
Held-to-maturity Securities, Unrealized Losses	(55)	(29)
Held-to-maturity Securities, Fair Value	1,156	1,442
Available-for-sale Securities, Amortized Cost	10,610	12,101
Available-for-sale Securities, Unrealized Losses	(669)	(447)
AFS investment securities	9,941	11,654
State and Municipal Taxable [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	362	363
Held-to-maturity Securities, Unrealized Losses	(10)	(8)
Held-to-maturity Securities, Fair Value	352	355
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	37,519	37,530
Held-to-maturity Securities, Unrealized Gains	2	59
Held-to-maturity Securities, Unrealized Losses	(1,722)	(405)
Held-to-maturity Securities, Fair Value	35,799	37,184
Available-for-sale Securities, Amortized Cost	1,983	1,991
Available-for-sale Securities, Unrealized Losses	(187)	(63)
AFS investment securities	$ 1,796	$ 1,928

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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