Acquisitions - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jul. 08, 2014
Business Acquisition [Line Items]
Amortization expense of intangibles	$ 93,000	$ 89,000	$ 283,000	$ 200,000
Path Logic [Member]
Business Acquisition [Line Items]
Business acquisition purchase price					$ 5,908,000
Acquired intangible assets					$ 1,930,000
Amortization expense of intangibles	37,000		$ 111,000
Intangible asset amortization period			13 years
Goodwill expected tax deductible amount	3,700,000		$ 3,700,000
Goodwill amortization period for tax purposes			15 years
Transaction costs related to acquisition	$ 361,000		$ 361,000