Property, Plant and Equipment - Depreciation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment
Depreciation	$ 172,600	$ 166,200	$ 166,900
Capital lease obligations	0	0
Accounts payable	53,147	103,401
Inventory to property, plant and equipment transfer amount	20,800	23,100
Property and Equipment
Property, Plant and Equipment
Accounts payable	$ 6,800	$ 14,800	$ 7,100