Goodwill and Intangible Assets - Summary of Acquisition-Related Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Net Carrying Value	$ 628	$ 729
Customer relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,275	1,275
Accumulated Amortization	(647)	(546)
Net Carrying Value	$ 628	$ 729