Income Taxes - Components of Income (Loss) and Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes
Loss before income taxes	$ (177,855)	$ (294,564)	$ 85,436
Components of the provision for income taxes attributable to income (loss) before income taxes
Current	35,432	12,777	44,486
Deferred	9,505	(23,561)	110,786
Income tax expense (benefit)	44,937	(10,784)	155,272
Reconciliation of income tax expense and the reported effective tax rate
Tax at Bermuda statutory rate	0	0	0
Foreign income (loss) taxed at different rates	(1,978)	(57,898)	94,184
Change in valuation allowance and the expiration of fully valued deferred tax assets	6,008	29,263	40,600
Non-deductible and other items	21,100	12,347	1,885
Tax shortfall on equity-based compensation	3,086	5,504	18,603
Change in U.S. tax rate	$ 16,721	$ 0	$ 0
Effective tax rate	25.00%	4.00%	182.00%
Impact of losses incurred in jurisdictions in which company is not subject to taxes on effective tax rate	$ 164,400	$ 121,400	$ 153,500
Tax related interest expense	4,700
Bermuda
Income Taxes
Loss before income taxes	(66,914)	(63,749)	(62,372)
Components of the provision for income taxes attributable to income (loss) before income taxes
Current	0	0	0
Deferred	0	0	0
United States
Income Taxes
Loss before income taxes	6,068	5,083	10,652
Components of the provision for income taxes attributable to income (loss) before income taxes
Current	10,976	12,675	15,199
Deferred	15,310	(3,594)	8,241
Foreign—other
Income Taxes
Loss before income taxes	(117,009)	(235,898)	137,156
Components of the provision for income taxes attributable to income (loss) before income taxes
Current	24,456	102	29,287
Deferred	(5,805)	$ (19,967)	$ 102,545
Morocco
Reconciliation of income tax expense and the reported effective tax rate
Tax expense from tax loss carryforward	$ 5,000