Securities - Summary of Amortized Costs and Fair Values of Securities Available for Sale (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 Securities, Debt and Equity, Amortized Cost Basis, Total	$ 105,851	$ 83,494
Securities available for sale, Gross Unrealized Gains	601	704
Securities available for sale, Gross Unrealized (Losses)	(893)	(906)
Securities available for sale, Fair Value	105,559	83,292
Securities held to maturity, Amortized Cost	66,519
Securities held to maturity, Gross Unrealized Gains	264
Securities held to maturity, Gross Unrealized (Losses)	(345)
Securities held to maturity, Fair Value	66,438	0
Total securities, Amortized Cost	172,370
Total securities, Gross Unrealized Gains	865
Total securities, Gross Unrealized (Losses)	(1,238)
Total securities, Fair Value	171,997
U.S. Agency and Mortgage-Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Debt and Equity, Amortized Cost Basis, Total	89,919	67,462
Securities available for sale, Gross Unrealized Gains	261	374
Securities available for sale, Gross Unrealized (Losses)	(843)	(807)
Securities available for sale, Fair Value	89,337	67,029
Securities held to maturity, Amortized Cost	49,662
Securities held to maturity, Gross Unrealized Gains	36
Securities held to maturity, Gross Unrealized (Losses)	(326)
Securities held to maturity, Fair Value	49,372
Obligations of States and Political Subdivisions [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Debt and Equity, Amortized Cost Basis, Total	15,931	16,031
Securities available for sale, Gross Unrealized Gains	333	325
Securities available for sale, Gross Unrealized (Losses)	(50)	(99)
Securities available for sale, Fair Value	16,214	16,257
Securities held to maturity, Amortized Cost	15,357
Securities held to maturity, Gross Unrealized Gains	228
Securities held to maturity, Gross Unrealized (Losses)	(19)
Securities held to maturity, Fair Value	15,566
Corporate Equity Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Debt and Equity, Amortized Cost Basis, Total	1	1
Securities available for sale, Gross Unrealized Gains	7	5
Securities available for sale, Fair Value	8	$ 6
Corporate Debt Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Securities held to maturity, Amortized Cost	1,500
Securities held to maturity, Fair Value	$ 1,500

Available for sale and held to maturity securities accumulated gross unrealized loss.

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Available for sale securities and held to maturity securities accumulated gross unrealized gain.

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Schedule Of Available For Sale And Held To Maturity 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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This item represents the cost of debt and equity 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 and equity financial instruments classified as either held-to-maturity or available-for-sale.

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

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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