Investment Securities - Investment Securities Available-for-Sale and Held-to-Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-Sale, Amortized Cost	$ 197,995	$ 202,039
Available-for-Sale, Gross Unrealized Gains	2,093	3,306
Available-for-Sale, Gross Unrealized Losses	(1,245)	(379)
Available-for-Sale, Estimated Fair Value	198,843	204,966
Held-to-Maturity, Amortized Cost	32,359	29,120
Held-to-Maturity, Gross Unrealized Gains	70	88
Held-to-Maturity, Gross Unrealized Losses	(245)	(54)
Held-to-Maturity, Estimated Fair Value	32,184	29,154
Residential [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-Sale, Amortized Cost	135,104	139,980
Available-for-Sale, Gross Unrealized Gains	998	1,896
Available-for-Sale, Gross Unrealized Losses	(608)	(192)
Available-for-Sale, Estimated Fair Value	135,494	141,684
Commercial [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-Sale, Amortized Cost	45,961	35,873
Available-for-Sale, Gross Unrealized Gains	164	164
Available-for-Sale, Gross Unrealized Losses	(616)	(93)
Available-for-Sale, Estimated Fair Value	45,509	35,944
Held-to-Maturity, Amortized Cost	16,321	10,666
Held-to-Maturity, Gross Unrealized Gains	33	65
Held-to-Maturity, Gross Unrealized Losses	(170)	(2)
Held-to-Maturity, Estimated Fair Value	16,184	10,729
Obligations of States and Political Subdivisions [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-Sale, Amortized Cost	14,071	15,673
Available-for-Sale, Gross Unrealized Gains	931	1,241
Available-for-Sale, Gross Unrealized Losses	(4)
Available-for-Sale, Estimated Fair Value	14,998	16,914
Held-to-Maturity, Amortized Cost	2,272	584
Held-to-Maturity, Gross Unrealized Gains	18	4
Held-to-Maturity, Gross Unrealized Losses	(4)
Held-to-Maturity, Estimated Fair Value	2,286	588
Obligations of U.S. Government Sponsored Agencies [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-Sale, Amortized Cost	1,999	6,360
Available-for-Sale, Gross Unrealized Gains		5
Available-for-Sale, Gross Unrealized Losses	(17)	(1)
Available-for-Sale, Estimated Fair Value	1,982	6,364
Held-to-Maturity, Amortized Cost	13,766	17,870
Held-to-Maturity, Gross Unrealized Gains	19	19
Held-to-Maturity, Gross Unrealized Losses	(71)	(52)
Held-to-Maturity, Estimated Fair Value	13,714	17,837
Corporate Notes [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-Sale, Amortized Cost	780
Available-for-Sale, Estimated Fair Value	780
U.S. Treasury Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-Sale, Amortized Cost	80	4,153
Available-for-Sale, Gross Unrealized Losses		(93)
Available-for-Sale, Estimated Fair Value	$ 80	$ 4,060

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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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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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Schedule of available for sale and held to maturity securities.

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