Effective Income Tax Rate Reconciliation, Change in Enacted Foreign Tax Rate, Percent

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Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Other than United States

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Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, United States

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Taxation - Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
(Loss) income from continuing operations before income taxes									$ (449,851)	$ (154,406)	$ 79,473
Less: income tax expense (benefit)									441	(6,757)	413
Net (loss) income from continuing operations	$ (216,692)	$ (240,413)	$ (5,535)	$ 12,348	$ (116,466)	$ (43,983)	$ (1,927)	$ 14,727	$ (450,292)	$ (147,649)	$ 79,060
Reconciliation of effective tax rate (% of income before income taxes)
Bermuda tax rate									0.00%	0.00%	0.00%
U.S. taxes at statutory rates									1.10%	9.60%	(5.80%)
Rate change in the U.S.									0.00%	3.20%	0.00%
Valuation allowance in respect of U.S. taxes									(1.10%)	(8.30%)	5.80%
Other jurisdictions									(0.10%)	(0.10%)	0.50%
Actual tax rate									(0.10%)	4.40%	0.50%