Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 68,138	$ 67,022
Held-to-maturity Securities, Unrealized Gains	622	593
Held-to-maturity Securities, Unrealized Losses	(1,123)	(1,491)
Held-to-maturity Securities, Fair Value	67,637	66,124
Available-for-sale Securities, Amortized Cost	111,779	116,830
Available-for-sale Securities, Unrealized Gains	18	41
Available-for-sale Securities, Unrealized Losses	(1,513)	(1,687)
AFS investment securities	110,284	115,184
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,288	8,224
Held-to-maturity Securities, Unrealized Gains	295	309
Held-to-maturity Securities, Fair Value	8,583	8,533
Available-for-sale Securities, Amortized Cost	49,423	52,428
Available-for-sale Securities, Unrealized Gains	6	31
Available-for-sale Securities, Unrealized Losses	(145)	(150)
AFS investment securities	49,284	52,309
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,347	1,440
Held-to-maturity Securities, Unrealized Gains	35	38
Held-to-maturity Securities, Fair Value	1,382	1,478
Available-for-sale Securities, Amortized Cost	29,640	30,861
Available-for-sale Securities, Unrealized Gains		2
Available-for-sale Securities, Unrealized Losses	(643)	(723)
AFS investment securities	28,997	30,140
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	14,139	12,825
Held-to-maturity Securities, Unrealized Gains	249	230
Held-to-maturity Securities, Unrealized Losses	(23)	(63)
Held-to-maturity Securities, Fair Value	14,365	12,992
Available-for-sale Securities, Amortized Cost	15,427	15,474
Available-for-sale Securities, Unrealized Gains	7	5
Available-for-sale Securities, Unrealized Losses	(233)	(299)
AFS investment securities	15,201	15,180
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,806	1,966
Held-to-maturity Securities, Unrealized Gains	3	2
Held-to-maturity Securities, Unrealized Losses	(20)	(22)
Held-to-maturity Securities, Fair Value	1,789	1,946
Available-for-sale Securities, Amortized Cost	12,190	12,957
Available-for-sale Securities, Unrealized Gains	5	3
Available-for-sale Securities, Unrealized Losses	(373)	(387)
AFS investment securities	11,822	12,573
State and Municipal Taxable [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,008	1,008
Held-to-maturity Securities, Unrealized Gains		6
Held-to-maturity Securities, Unrealized Losses	(1)
Held-to-maturity Securities, Fair Value	1,007	1,014
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	41,550	41,559
Held-to-maturity Securities, Unrealized Gains	40	8
Held-to-maturity Securities, Unrealized Losses	(1,079)	(1,406)
Held-to-maturity Securities, Fair Value	40,511	40,161
Available-for-sale Securities, Amortized Cost	5,073	5,084
Available-for-sale Securities, Unrealized Losses	(119)	(128)
AFS investment securities	4,954	4,956
Asset-Backed Security [Member]
Securities [Line Items]
Available-for-sale Securities, Amortized Cost	26	26
AFS investment securities	$ 26	$ 26

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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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