Taxation - Tax Expense for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Domestic (Bermuda)									$ 0	$ 0	$ 0
Foreign									39,396	39,455	30,787
Total current tax expense									39,396	39,455	30,787
Deferred:
Domestic (Bermuda)									0	0	0
Foreign									(21,578)	(28,313)	4,832
Total deferred tax expense									(21,578)	(28,313)	4,832
Total tax expense	$ (11,004)	$ 12,262	$ 5,816	$ 10,744	$ (10,246)	$ 5,660	$ 8,452	$ 7,276	$ 17,818	$ 11,142	$ 35,619