Condensed Consolidated Statements of Comprehensive Income Parenthetical (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Foreign currency translation gain (loss), tax	$ (0.1)	$ 0	$ (0.2)	$ 0
Net gain arising from remeasurement during the period, tax	13.1		17.3
Amortization of prior service benefits, tax	(1.3)	(1.2)	(3.7)	(3.5)
Amortization of net actuarial loss, tax	2.4	2.2	7.5	7.0
Reclassification adjustment for curtailment gain included in net income, tax			$ (0.2)