Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Effective tax rate	40.90%	40.90%	40.20%	40.20%
Total gross amount of unrecognized tax benefits that would impact effective tax rate	$ 1.9		$ 1.9		$ 1.6
Potential impact on total gross amount of unrecognized tax benefits	$ 1.3		$ 1.3