Commitments and Contingencies - Narrative (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Future minimum payments on noncancelable leases in 2013	$ 3.7
Future minimum payments on noncancelable leases in 2014	2.8
Future minimum payments on noncancelable leases in 2015	1.5
Future minimum payments on noncancelable leases in 2016	1.2
Future minimum payments on noncancelable leases in 2017	1.2
Future minimum payments on noncancelable leases due in later years	8.1
Future minimum payments on contractual commitments in 2013	37.0
Future minimum payments on contractual commitments in 2014	23.4
Future minimum payments on contractual commitments in 2015	7.8
Future minimum payments on contractual commitments in 2016	2.0
Future minimum payments on contractual commitments in 2017	0.6
Future minimum payments on contractual commitments due in later years	0
Continuing operations
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Rental expense	10.3	7.8	8.5
Discontinued operations
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Rental expense			$ 1.1