Income Taxes - Schedule of Interest Expense and Penalties (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Net increase (decrease) in interest expense related to uncertain tax positions	$ (92)	$ (4,761)	$ (5,283)
Net increase (decrease) in penalties related to uncertain tax positions	$ (23,172)	$ 2,302	$ (22,175)