Income Tax Matters, Textuals (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		36 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Income Tax Matters [Line Items]
The foreign currency impact on gross unrecognized tax benefits, interest and penalties resulted in an increase to currency translation adjustment	$ (0.5)	$ 0.8	$ (0.4)	$ 0.5
Income Tax Matters (Textuals) [Abstract]
Income tax provision	18.2	0.4	47.7	9.4
Effective tax rate			38.40%	33.20%
Increase (decrease) in unrecognized tax benefit, interest and penalty expense			0.7	(0.4)
Increase (decrease) in effective tax rate due to unrecognized tax benefits including interest and penalty			0.60%	(1.60%)
Decrease in valuation allowance due to change in tax law				0.8
Decrease in effective tax rate due to change in valuation allowance				2.90%
Decrease related to a return to provision adjustment				0.2
Decrease in effective tax rate related to a return to provision adjustment				(0.80%)
Impact of non-deductible compensation expense				0.2
Increase in effective tax rate due to non-deductible compensation expense				0.50%
Net operating loss carryforwards					875.1
NOL carry forwards relates to the excess tax benefits from employee restricted stock					1.7
Alternate minimum tax					29.8
Valuation allowance against deferred tax assets	18.8		18.8		18.8
Canadian provincial income tax assessment settlement					9.2
Gross unrecognized tax benefits	14.3		14.3		13.7
Accrued Interest and penalties related to these unrecognized tax benefits	7.4		7.4		6.6
Expected period which gross unrecognized tax benefits will not be reduced	12 months		12 months
FIN 48
Income Tax Matters [Line Items]
The foreign currency impact on gross unrecognized tax benefits, interest and penalties resulted in an increase to currency translation adjustment			$ (0.5)