Supplemental Cash Flows Information - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Cash paid for interest, net of amounts capitalized	$ 26.4	$ 42.0	$ 43.1
Capital expenditures incurred but not yet paid	$ 66.9	$ 74.8	$ 36.7