Income Taxes - Summary of Income Tax Contingencies (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Balance at January 1	$ 256	$ 1,318	$ 7,943
Additions for tax positions taken during current year	3,000
Additions for tax positions taken during a prior year	8	256	405
Settlements with taxing authorities			(7,030)
Reductions due to lapse of applicable statute of limitations		(1,318)
Balance at December 31	$ 3,264	$ 256	$ 1,318