Property, Plant, and Equipment - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Depreciation [Abstract]
Depreciation expense	$ 85.2	$ 94.6
Incremental depreciation	0.2	$ 8.3
Purchases of property, plant, and equipment included in accounts payable	$ 34.3		$ 24.7