Goodwill and Other Intangible Assets - Amortization Expense Related to Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense related to intangible assets	$ 700	$ 1,090	$ 1,738	$ 2,730