Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 67,249	$ 67,022
Held-to-maturity Securities, Unrealized Gains	656	593
Held-to-maturity Securities, Unrealized Losses	(517)	(1,491)
Held-to-maturity Securities, Fair Value	67,388	66,124
Available-for-sale Securities, Amortized Cost	111,319	116,830
Available-for-sale Securities, Unrealized Gains	5	41
Available-for-sale Securities, Unrealized Losses	(1,424)	(1,687)
AFS investment securities	109,900	115,184
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,352	8,224
Held-to-maturity Securities, Unrealized Gains	276	309
Held-to-maturity Securities, Fair Value	8,628	8,533
Available-for-sale Securities, Amortized Cost	53,301	52,428
Available-for-sale Securities, Unrealized Gains		31
Available-for-sale Securities, Unrealized Losses	(222)	(150)
AFS investment securities	53,079	52,309
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	547	1,440
Held-to-maturity Securities, Unrealized Gains	14	38
Held-to-maturity Securities, Fair Value	561	1,478
Available-for-sale Securities, Amortized Cost	31,719	30,861
Available-for-sale Securities, Unrealized Gains		2
Available-for-sale Securities, Unrealized Losses	(587)	(723)
AFS investment securities	31,132	30,140
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	14,108	12,825
Held-to-maturity Securities, Unrealized Gains	270	230
Held-to-maturity Securities, Unrealized Losses	(1)	(63)
Held-to-maturity Securities, Fair Value	14,377	12,992
Available-for-sale Securities, Amortized Cost	11,033	15,474
Available-for-sale Securities, Unrealized Gains	5	5
Available-for-sale Securities, Unrealized Losses	(150)	(299)
AFS investment securities	10,888	15,180
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,693	1,966
Held-to-maturity Securities, Unrealized Gains	3	2
Held-to-maturity Securities, Unrealized Losses	(15)	(22)
Held-to-maturity Securities, Fair Value	1,681	1,946
Available-for-sale Securities, Amortized Cost	13,270	12,957
Available-for-sale Securities, Unrealized Gains		3
Available-for-sale Securities, Unrealized Losses	(386)	(387)
AFS investment securities	12,884	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	3	6
Held-to-maturity Securities, Fair Value	1,011	1,014
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	41,541	41,559
Held-to-maturity Securities, Unrealized Gains	90	8
Held-to-maturity Securities, Unrealized Losses	(501)	(1,406)
Held-to-maturity Securities, Fair Value	41,130	40,161
Available-for-sale Securities, Amortized Cost	1,996	5,084
Available-for-sale Securities, Unrealized Losses	(79)	(128)
AFS investment securities	$ 1,917	4,956
Asset-Backed Security [Member]
Securities [Line Items]
Available-for-sale Securities, Amortized Cost		26
AFS investment securities		$ 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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