Restructuring (2011 Restructuring) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended				3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Jun. 30, 2012 2011 Restructuring Plan [Member]	Jun. 30, 2012 Customer Management [Member]	Jun. 30, 2011 Customer Management [Member]	Jun. 30, 2012 Customer Management [Member]	Jun. 30, 2011 Customer Management [Member]	Dec. 31, 2011 Professional Employees [Member] 2011 Restructuring Plan [Member]	Dec. 31, 2011 Severance Charge [Member] 2011 Restructuring Plan [Member]	Dec. 31, 2011 Severance Charge [Member] Customer Management [Member] 2011 Restructuring Plan [Member]	Dec. 31, 2011 Severance Charge [Member] Corporate [Member] 2011 Restructuring Plan [Member]
Restructuring Charges	$ 7.6	$ 0	$ 7.6	$ 0			$ 1.2	$ 0	$ 1.2	$ 0		$ 1.2	$ 1.0	$ 0.2
Restructuring liability, ending balance					$ 0.2	$ 0.2
Employees affected											50