CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement of Other Comprehensive Income [Abstract]
Net income	$ 80.7	$ 75.5	$ 65.3
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	7.0	(11.8)	(13.0)
Prior service credit arising during period, net of tax of $2.0	0	0	3.2
Net actuarial loss arising during period, net of tax of $(6.2), $(17.9) and $(2.6)	(13.2)	(30.1)	(5.0)
Curtailment arising during period, net of tax of $(0.2)	0	(0.4)	0
Settlement effects arising during period, net of tax of $0.3	0	0.5	0
Less: amortization of actuarial loss, net of tax of $2.8, $2.2 and $2.1	5.7	3.8	3.4
Less: amortization of prior service credit, net of tax of $(0.5), $(0.5) and $(0.4)	(0.8)	(0.9)	(0.6)
Less: amortization of transition obligation	0.1	0.1	0.1
Net gains on investment securities, net of tax of $0.2, $0.2 and $0.4	0.4	0.3	0.6
Net losses on derivatives, net of tax of $(2.1), $(1.1) and $(0.2)	(3.6)	(1.7)	(0.3)
Other comprehensive loss, net of tax	(4.4)	(40.2)	(11.6)
Comprehensive income	$ 76.3	$ 35.3	$ 53.7