Debt (Details) (USD $) In Millions, unless otherwise specified			9 Months Ended		9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Credit Agreement Minimum	Feb. 29, 2008 Credit Agreement Minimum	Sep. 30, 2012 Credit Agreement Maximum	Feb. 29, 2008 Credit Agreement Maximum	Feb. 29, 2008 Credit Agreement Prime or Federal Funds	Feb. 29, 2008 Credit Agreement LIBOR Minimum	Feb. 29, 2008 Credit Agreement LIBOR Maximum	Sep. 30, 2012 U.S. Dollar term loan under the Amended Credit Agreement	Dec. 31, 2011 U.S. Dollar term loan under the Amended Credit Agreement	Sep. 30, 2012 U.S. Dollar revolving loans under the Amended Credit Agreement	Dec. 31, 2011 U.S. Dollar revolving loans under the Amended Credit Agreement	May 31, 2011 U.S. Dollar revolving loans under the Amended Credit Agreement	Feb. 29, 2008 U.S. Dollar revolving loans under the Amended Credit Agreement	Sep. 30, 2012 U.S. Dollar revolving loans under the Amended Credit Agreement Minimum	Sep. 30, 2012 U.S. Dollar revolving loans under the Amended Credit Agreement Maximum	Sep. 30, 2012 U.S. Dollar revolving loans under the Amended Credit Agreement LIBOR	Sep. 30, 2012 U.S. Dollar revolving loans under the Amended Credit Agreement Adjusted LIBOR Minimum	Sep. 30, 2012 U.S. Dollar revolving loans under the Amended Credit Agreement Adjusted LIBOR Maximum	Sep. 30, 2012 U.S. Dollar revolving loans under the Amended Credit Agreement Federal Funds	Sep. 30, 2012 US Dollar note under the Note Purchase Agreement	Sep. 30, 2012 Capital lease obligations and other loans	Dec. 31, 2011 Capital lease obligations and other loans	Sep. 30, 2012 Other revolving loans
Debt
Total debt	$ 336.9	$ 303.1								$ 37.5	$ 82.5	$ 55.0	$ 216.5									$ 240.0	$ 4.4	$ 4.1
Current portion of long-term debt	(38.9)	(83.7)
Total long-term debt, less current portion	298.0	219.4
Maximum commitment												250.0		250.0	230.0										177.2
Term facility															$ 150
Interest rate added to base rate (as a percent)							0.50%	0.40%	1.25%									1.00%	0.80%	1.65%	0.50%
Facility fee (as a percent)				0.10%		0.20%										0.20%	0.35%
Weighted Average Interest Rate (as a percent)										2.70%		1.40%
Leverage ratio			3.0
Interest coverage ratio					3.0