Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 67,140	$ 67,022
Held-to-maturity Securities, Unrealized Gains	609	593
Held-to-maturity Securities, Unrealized Losses	(520)	(1,491)
Held-to-maturity Securities, Fair Value	67,229	66,124
Available-for-sale Securities, Amortized Cost	109,262	116,830
Available-for-sale Securities, Unrealized Gains	9	41
Available-for-sale Securities, Unrealized Losses	(1,263)	(1,687)
AFS investment securities	108,008	115,184
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,418	8,224
Held-to-maturity Securities, Unrealized Gains	242	309
Held-to-maturity Securities, Fair Value	8,660	8,533
Available-for-sale Securities, Amortized Cost	53,311	52,428
Available-for-sale Securities, Unrealized Gains		31
Available-for-sale Securities, Unrealized Losses	(209)	(150)
AFS investment securities	53,102	52,309
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	525	1,440
Held-to-maturity Securities, Unrealized Gains	14	38
Held-to-maturity Securities, Fair Value	539	1,478
Available-for-sale Securities, Amortized Cost	30,270	30,861
Available-for-sale Securities, Unrealized Gains		2
Available-for-sale Securities, Unrealized Losses	(498)	(723)
AFS investment securities	29,772	30,140
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	14,077	12,825
Held-to-maturity Securities, Unrealized Gains	286	230
Held-to-maturity Securities, Unrealized Losses	(4)	(63)
Held-to-maturity Securities, Fair Value	14,359	12,992
Available-for-sale Securities, Amortized Cost	11,009	15,474
Available-for-sale Securities, Unrealized Gains	9	5
Available-for-sale Securities, Unrealized Losses	(114)	(299)
AFS investment securities	10,904	15,180
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,580	1,966
Held-to-maturity Securities, Unrealized Gains	2	2
Held-to-maturity Securities, Unrealized Losses	(15)	(22)
Held-to-maturity Securities, Fair Value	1,567	1,946
Available-for-sale Securities, Amortized Cost	12,678	12,957
Available-for-sale Securities, Unrealized Gains		3
Available-for-sale Securities, Unrealized Losses	(370)	(387)
AFS investment securities	12,308	12,573
State and Municipal Taxable [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,007	1,008
Held-to-maturity Securities, Unrealized Gains		6
Held-to-maturity Securities, Unrealized Losses	(18)
Held-to-maturity Securities, Fair Value	989	1,014
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	41,533	41,559
Held-to-maturity Securities, Unrealized Gains	65	8
Held-to-maturity Securities, Unrealized Losses	(483)	(1,406)
Held-to-maturity Securities, Fair Value	41,115	40,161
Available-for-sale Securities, Amortized Cost	1,994	5,084
Available-for-sale Securities, Unrealized Losses	(72)	(128)
AFS investment securities	$ 1,922	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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