Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2018

Property, Plant and Equipment [Abstract]

Summary of property, plant and equipment

Property, plant and equipment consisted of the following:

	March 31, 2018		December 31, 2017
	(in millions)
Land and improvements	$	47.4	$	47.4
Buildings	83.9		83.3
Machinery and equipment	3,741.4		3,733.8
Automotive equipment	24.8		24.7
Furniture and fixtures	33.0		32.4
Leasehold improvements	4.6		4.6
Aircraft	3.6		3.6
Railcars	16.8		16.8
Construction in progress	64.7		56.2
	4,020.2		4,002.8
Less: Accumulated depreciation	1,482.6		1,431.0
Total property, plant and equipment, net	$	2,537.6	$	2,571.8