Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	$ 67,022	$ 67,829
Held-to-maturity Securities, Unrealized Gains	593	946
Held-to-maturity Securities, Unrealized Losses	(1,491)	(344)
Held-to-maturity Securities, Fair Value	66,124	68,431
Available-for-sale Securities, Amortized Cost	116,830	153,559
Available-for-sale Securities, Unrealized Gains	41	196
Available-for-sale Securities, Unrealized Losses	(1,687)	(1,376)
AFS investment securities	115,184	152,379
US Government Agency Obligations [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	8,224	7,973
Held-to-maturity Securities, Unrealized Gains	309	320
Held-to-maturity Securities, Fair Value	8,533	8,293
Available-for-sale Securities, Amortized Cost	52,428	58,460
Available-for-sale Securities, Unrealized Gains	31
Available-for-sale Securities, Unrealized Losses	(150)	(252)
AFS investment securities	52,309	58,208
Government Sponsored Entities (GSE) Mortgage-Backed Securities [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,440	2,759
Held-to-maturity Securities, Unrealized Gains	38	83
Held-to-maturity Securities, Fair Value	1,478	2,842
Available-for-sale Securities, Amortized Cost	30,861	40,663
Available-for-sale Securities, Unrealized Gains	2	13
Available-for-sale Securities, Unrealized Losses	(723)	(325)
AFS investment securities	30,140	40,351
Corporate Bonds [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	12,825	11,518
Held-to-maturity Securities, Unrealized Gains	230	234
Held-to-maturity Securities, Unrealized Losses	(63)	(42)
Held-to-maturity Securities, Fair Value	12,992	11,710
Available-for-sale Securities, Amortized Cost	15,474	20,921
Available-for-sale Securities, Unrealized Gains	5
Available-for-sale Securities, Unrealized Losses	(299)	(350)
AFS investment securities	15,180	20,571
Collateralized Mortgage Obligations GSE [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,966	2,623
Held-to-maturity Securities, Unrealized Gains	2	9
Held-to-maturity Securities, Unrealized Losses	(22)	(26)
Held-to-maturity Securities, Fair Value	1,946	2,606
Available-for-sale Securities, Amortized Cost	12,957	16,241
Available-for-sale Securities, Unrealized Gains	3	3
Available-for-sale Securities, Unrealized Losses	(387)	(438)
AFS investment securities	12,573	15,806
State And Municipal Taxable [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	1,008
Held-to-maturity Securities, Unrealized Gains	6
Held-to-maturity Securities, Fair Value	1,014
State and Municipal Tax-Exempt [Member]
Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	41,559	42,956
Held-to-maturity Securities, Unrealized Gains	8	300
Held-to-maturity Securities, Unrealized Losses	(1,406)	(276)
Held-to-maturity Securities, Fair Value	40,161	42,980
Available-for-sale Securities, Amortized Cost	5,084	17,274
Available-for-sale Securities, Unrealized Gains		180
Available-for-sale Securities, Unrealized Losses	(128)	(11)
AFS investment securities	4,956	$ 17,443
Asset-Backed Security [Member]
Securities [Line Items]
Available-for-sale Securities, Amortized Cost	26
AFS investment securities	$ 26

Securities [Line Items]

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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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