Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accumulated Other Comprehensive Income (Loss) [Abstract]
Unrealized (loss) gain on derivatives qualifying as hedges, balance		$ (0.1)	$ (0.9)
Unrealized (loss) gain on derivatives qualifying as hedges, other comprehensive income		0.1	0.8
Unrealized (loss) gain on derivatives qualifying as hedges, balance			(0.1)
Unrealized gain (loss) on available for sale securities, other comprehensive income	(0.1)
Unrealized gain (loss) on available for sale securities, balance	(0.1)
Accumulated Other Comprehensive Income (Loss), balance		(0.1)	(0.9)
Accumulated Other Comprehensive Income (Loss), other comprehensive income	(0.1)	0.1	0.8
Accumulated Other Comprehensive Income (Loss), balance	$ (0.1)		$ (0.1)