Other Comprehensive Income (Loss) - Components of OCI (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Equity [Abstract]
Net actuarial gain (loss) during year, before tax		$ (1.6)	$ (2.1)	$ (4.8)
Net actuarial gain (loss) during year, tax effect		0.6	0.9	1.7
Net actuarial gain (loss) during year, net of tax		(1.0)	(1.2)	(3.1)
Settlement charge		1.3	1.6	0.0
Settlement charge, tax effect		(0.5)	(0.6)	0.0
Settlement charge, net of tax		0.8	1.0	0.0
Amortization of net actuarial loss, before tax		0.6	0.6	0.3
Amortization of net actuarial loss, tax effect		(0.2)	(0.2)	(0.1)
Amortization of net actuarial loss, net of tax		0.4	0.4	0.2
Net (loss) gain during the year, before tax		0.3	0.1	(4.5)
Net (loss) gain during the year, tax effect		(0.1)	0.1	1.6
Net (loss) gain during the year, net of tax		0.2	0.2	(2.9)
Foreign currency translation adjustment gain (loss), before tax		1.9	(4.9)	(3.0)
Foreign currency translation adjustment gain (loss), tax effect		0.0	0.0	0.0
Foreign currency translation adjustment gain (loss), net of tax		1.9	(4.9)	(3.0)
Other comprehensive (loss) income, before tax		2.2	(4.8)	(7.5)
Other comprehensive (loss) income, tax effect		(0.1)	0.1	1.6
Other comprehensive income (loss), net of tax	[1]	$ 2.1	$ (4.7)	$ (5.9)

[1] Amounts have been rounded for presentation purposes and might differ from unrounded results.