Components of Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current income tax expense (benefit):
Non-resident withholding			$ 6,250
Foreign	$ 330	$ 263	129
U.S. Federal	147	(1,785)	2,787
Total current income tax expense (benefit)	477	(1,522)	9,166
Deferred income tax benefit:
U.S. Federal	(2,727)	(7,201)	(828)
Total deferred income tax benefit	(2,727)	(7,201)	(828)
Actual taxes on continuing operations	$ (2,250)	$ (8,723)	$ 8,338