Supplemental Cash Flow Information (Details) - USD ($)
$ in Millions
 9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Supplemental Cash Flow [Line Items]    
Capital expenditures included in current liabilities [1] $ 211.0 $ 218.4
Cash paid for interest, net of interest capitalized amounts $ 22.3 $ 29.7
[1] Capital expenditures included in current liabilities is comprised of "Accrued capital expenditures" and certain other amounts included within "Accounts payable" on the Condensed Consolidated Balance Sheets (unaudited).