Income Taxes - Schedule of Reconciliation of Total Amounts of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Unrecognized Tax Benefits
Beginning of the period	$ 7,016	$ 2,353	$ 2,035
Increases of current year items	18	5,217	0
Increases of prior year items	739	0	318
Decreased for tax positions of prior years	0	(554)	0
End of the period	$ 7,773	$ 7,016	2,353
Unrecognized tax benefits for discontinued operations			$ 6,200