Goodwill and Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended		0 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Jul. 25, 2014
Finite-Lived Intangible Assets [Line Items]
Amortization expense for intangible assets	$ 52,000	$ 91,000
Amortization expense for software	58,000	49,000
Dynetic [Member]
Finite-Lived Intangible Assets [Line Items]
Purchase price of assets acquired and liabilities assumed			4,000,000
Business acquisition, date of agreement	Jul. 25, 2014
Working capital adjustment			27,000
Amount of earn-out liabilities	310,000
Earn-out liability	$ 288,000