Taxes - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($)
Operating Loss Carryforwards [Line Items]
Reduction in corporate income tax rate	21.00%
Tax Cuts and Jobs Act, accounting complete	false
Provisional income tax due to reduction in deferred tax assets	$ 143,500
Provisional amount of one-time transition tax	0
ASU 2016-16 [Member]
Operating Loss Carryforwards [Line Items]
Decrease in net operating loss deferred tax assets	834
Decrease in deferred tax assets valuation allowance	$ 834