Fair Value Measurements - Summary of Company's Securities Available-for-Sale (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	$ 64,839	$ 67,628
Gross unrealized gains	55	133
Gross unrealized losses	(31)	(19)
Securities available-for-sale	64,863us-gaap_AvailableForSaleSecurities	67,742us-gaap_AvailableForSaleSecurities
Municipal Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	11,693	16,049
Gross unrealized gains	5	9
Gross unrealized losses	(2)	(6)
Securities available-for-sale	11,696	16,052
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	53,146	51,579
Gross unrealized gains	50	124
Gross unrealized losses	(29)	(13)
Securities available-for-sale	$ 53,167	$ 51,690

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 gain in accumulated other comprehensive income (AOCI) on investments in debt and equity 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 and equity securities classified as available-for-sale.

+ References

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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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