Fair Value Measurements - Summary of Company's Securities Available-for-Sale (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	$ 62,068	$ 64,839
Gross unrealized gains	135	55
Gross unrealized losses	(8)	(31)
Securities available-for-sale	62,195us-gaap_AvailableForSaleSecurities	64,863us-gaap_AvailableForSaleSecurities
Municipal Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	9,083	11,693
Gross unrealized gains	2	5
Gross unrealized losses		(2)
Securities available-for-sale	9,085	11,696
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	52,985	53,146
Gross unrealized gains	133	50
Gross unrealized losses	(8)	(29)
Securities available-for-sale	$ 53,110	$ 53,167

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.

+ References

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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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-Publisher FASB

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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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