Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Statutory tax rate	21.00%	35.00%	35.00%
Tax benefit or expense recognized due to valuation allowance	$ 0	$ 0	$ 0
Deferred tax assets and liabilities related to revaluation		34,800
Uncertain tax positions, interest and penalties recognized	2	$ 95	$ 31
Luxembourg
Income Taxes [Line Items]
Net operating losses carryforward	$ 3,200

Income taxes line items.

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- Definition

Tax cuts and jobs act of 2017 change in tax rate income tax expense benefit.

+ References

No definition available.

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- Definition

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

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of other income tax expense (benefit).

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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