Long-Term Debt Long-Term Debt (Schedule of Revolving Credit Facility) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Outstanding borrowings		$ 1,078.6	$ 1,325.5
Outstanding letters of credit		43.4
Revolving Credit Facility [Member] | North America [Member]
Debt Instrument [Line Items]
Outstanding borrowings		136.3	136.8
Total credit under facility		1,000.0	1,000.0
Undrawn availability	[1]	$ 347.5	$ 425.0
Interest rate		2.50%	2.10%
Outstanding letters of credit		$ 36.7	$ 58.5
Original issuance		Jul. 31, 2011	Jul. 31, 2011
Maturity date		Sep. 30, 2018	Sep. 30, 2018
Revolving Credit Facility [Member] | UNITED STATES [Member]
Debt Instrument [Line Items]
Undrawn availability		$ 239.1	$ 257.7
Revolving Credit Facility [Member] | CANADA [Member]
Debt Instrument [Line Items]
Undrawn availability		34.8	54.3
Revolving Credit Facility [Member] | Europe [Member]
Debt Instrument [Line Items]
Undrawn availability		$ 73.6	$ 113.0

[1] Total undrawn availability for the U.S. borrower, the Canadian borrower and the European borrowers at December 31, 2015 is $239.1 million, $34.8 million and $73.6 million, respectively. Total undrawn availability for the U.S. borrower, the Canadian borrower and the European borrowers at December 31, 2014 is $257.7 million, $54.3 million and $113.0 million, respectively.