Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 73,789	$ 67,829
Held-to-maturity Securities, Unrealized Gains	1,342	946
Held-to-maturity Securities, Unrealized Losses	(20)	(344)
Held-to-maturity Securities, Fair Value	75,111	68,431
Available-for-sale Securities, Amortized Cost	121,492	153,559
Available-for-sale Securities, Unrealized Gains	462	196
Available-for-sale Securities, Unrealized Losses	(266)	(1,376)
Available-for-sale securities, Fair Value	121,688	152,379
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,161	7,973
Held-to-maturity Securities, Unrealized Gains	480	320
Held-to-maturity Securities, Fair Value	8,641	8,293
Available-for-sale Securities, Amortized Cost	52,436	58,460
Available-for-sale Securities, Unrealized Gains	121
Available-for-sale Securities, Unrealized Losses	(15)	(252)
Available-for-sale securities, Fair Value	52,542	58,208
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,545	2,759
Held-to-maturity Securities, Unrealized Gains	65	83
Held-to-maturity Securities, Fair Value	1,610	2,842
Available-for-sale Securities, Amortized Cost	32,605	40,663
Available-for-sale Securities, Unrealized Gains	236	13
Available-for-sale Securities, Unrealized Losses		(325)
Available-for-sale securities, Fair Value	32,841	40,351
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	12,854	11,518
Held-to-maturity Securities, Unrealized Gains	414	234
Held-to-maturity Securities, Unrealized Losses	(6)	(42)
Held-to-maturity Securities, Fair Value	13,262	11,710
Available-for-sale Securities, Amortized Cost	17,522	20,921
Available-for-sale Securities, Unrealized Gains	69
Available-for-sale Securities, Unrealized Losses	(140)	(350)
Available-for-sale securities, Fair Value	17,451	20,571
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	2,148	2,623
Held-to-maturity Securities, Unrealized Gains	30	9
Held-to-maturity Securities, Unrealized Losses		(26)
Held-to-maturity Securities, Fair Value	2,178	2,606
Available-for-sale Securities, Amortized Cost	13,834	16,241
Available-for-sale Securities, Unrealized Gains	28	3
Available-for-sale Securities, Unrealized Losses	(107)	(438)
Available-for-sale securities, Fair Value	13,755	15,806
State And Municipal Taxable [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,009
Held-to-maturity Securities, Unrealized Gains	40
Held-to-maturity Securities, Fair Value	1,049
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	48,072	42,956
Held-to-maturity Securities, Unrealized Gains	313	300
Held-to-maturity Securities, Unrealized Losses	(14)	(276)
Held-to-maturity Securities, Fair Value	48,371	42,980
Available-for-sale Securities, Amortized Cost	5,095	17,274
Available-for-sale Securities, Unrealized Gains	8	180
Available-for-sale Securities, Unrealized Losses	(4)	(11)
Available-for-sale securities, Fair Value	$ 5,099	$ 17,443

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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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