Income Tax Matters, Textuals (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2013
Income Tax Examination [Line Items]
Income tax provision	$ 9.4		$ 8.2
Effective tax rate	37.40%		19.70%
Cash tax benefit from settlement of tax audit			7.6
Cash received from settlement of tax audit	7.2
Cash tax benefit from advance pricing agreement		2.8
Gross unrecognized tax benefits	3.7			3.8
Gross unrecognized tax benefits that would impact effective tax rate	2.6			2.7
Reduction in gross unrecognized tax benefits	1.5
Period which gross unrecognized tax benefits are expected to be reduced	12 months
Audit settlement with the Canada Revenue Agency Competent Authority
Income Tax Examination [Line Items]
Decrease in unrecognized tax benefits due to an audit settlement with the Canada Revenue Agency Competent Authority			$ (7.5)
Decrease in effective tax rate, percent			(17.90%)