Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 62,145	$ 62,390
Held-to-maturity Securities, Unrealized Gains	202	474
Held-to-maturity Securities, Unrealized Losses	(1,532)	(444)
Held-to-maturity Securities, Fair Value	60,815	62,420
Available-for-sale Securities, Amortized Cost	106,450	113,555
Available-for-sale Securities, Unrealized Gains		12
Available-for-sale Securities, Unrealized Losses	(3,021)	(1,784)
AFS investment securities	103,429	111,783
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,615	8,483
Held-to-maturity Securities, Unrealized Gains	56	163
Held-to-maturity Securities, Fair Value	8,671	8,646
Available-for-sale Securities, Amortized Cost	50,070	53,279
Available-for-sale Securities, Unrealized Losses	(621)	(386)
AFS investment securities	49,449	52,893
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	443	496
Held-to-maturity Securities, Unrealized Gains		9
Held-to-maturity Securities, Unrealized Losses	(1)
Held-to-maturity Securities, Fair Value	442	505
Available-for-sale Securities, Amortized Cost	30,328	33,203
Available-for-sale Securities, Unrealized Losses	(1,348)	(715)
AFS investment securities	28,980	32,488
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	13,913	14,047
Held-to-maturity Securities, Unrealized Gains	136	243
Held-to-maturity Securities, Unrealized Losses	(72)	(2)
Held-to-maturity Securities, Fair Value	13,977	14,288
Available-for-sale Securities, Amortized Cost	12,936	12,981
Available-for-sale Securities, Unrealized Gains		12
Available-for-sale Securities, Unrealized Losses	(275)	(173)
AFS investment securities	12,661	12,820
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,291	1,471
Held-to-maturity Securities, Unrealized Losses	(51)	(29)
Held-to-maturity Securities, Fair Value	1,240	1,442
Available-for-sale Securities, Amortized Cost	11,130	12,101
Available-for-sale Securities, Unrealized Losses	(608)	(447)
AFS investment securities	10,522	11,654
State and Municipal Taxable [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	362	363
Held-to-maturity Securities, Unrealized Losses	(12)	(8)
Held-to-maturity Securities, Fair Value	350	355
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	37,521	37,530
Held-to-maturity Securities, Unrealized Gains	10	59
Held-to-maturity Securities, Unrealized Losses	(1,396)	(405)
Held-to-maturity Securities, Fair Value	36,135	37,184
Available-for-sale Securities, Amortized Cost	1,986	1,991
Available-for-sale Securities, Unrealized Losses	(169)	(63)
AFS investment securities	$ 1,817	$ 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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