Commitments and Contingencies - Activity in Recorded Environmental Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Accrual for Environmental Loss Contingencies [Roll Forward]
Balance at beginning of period	$ 49,569
Expenditures	(3,133)
Accretion of discount	567
Additions and changes in estimates	1,070
Foreign currency translation adjustments and other	(1,269)
Balance at end of period	$ 49,569	$ 46,804
Less amounts reported in Accrued expenses		9,654
Amounts reported in Other noncurrent liabilities		$ 37,150