Financial Instruments and Fair Value Measurements (Nonfinancial Assets Measured and Recorded at Fair Value on a Nonrecurring Basis) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Franchise rights, Gain/(Loss)	$ (4.2)	$ 0	$ 0
Nonrecurring [Member] | Long Lived Assets, Fair Value Disclosure, Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held for sale, Gain/(Loss)	(0.1)	(1.6)
Long Lived Assets, Fair Value Disclosure, Adjustments [Member] | Nonrecurring [Member] | Continuing Operations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held for sale, Gain/(Loss)	0	(1.1)
Long Lived Assets, Fair Value Disclosure, Adjustments [Member] | Nonrecurring [Member] | Fair Value [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held for sale measured at fair value	3.7	24.8
Long Lived Assets, Fair Value Disclosure, Adjustments [Member] | Nonrecurring [Member] | Fair Value [Member] | Continuing Operations [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held for sale measured at fair value	0	13.9
Long Lived Assets, Fair Value Disclosure, Impairment Loss [Member] | Nonrecurring [Member] | Continuing Operations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held and used, Gain/(Loss)	(0.8)	(1.1)
Long-lived assets held for sale, Gain/(Loss)		(1.5)
Long Lived Assets, Fair Value Disclosure, Impairment Loss [Member] | Nonrecurring [Member] | Discontinued Operations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held for sale, Gain/(Loss)	(0.1)	(0.5)
Long Lived Assets, Fair Value Disclosure, Impairment Loss [Member] | Nonrecurring [Member] | Fair Value [Member] | Continuing Operations [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held and used measured at fair value	0	15.8
Long-lived assets held for sale measured at fair value		12.9
Long Lived Assets, Fair Value Disclosure, Impairment Loss [Member] | Nonrecurring [Member] | Fair Value [Member] | Discontinued Operations [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held for sale measured at fair value	3.7	10.9
Franchise rights [Member] | Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Franchise rights, Gain/(Loss)	(4.2)	0	0
Franchise rights [Member] | Nonrecurring [Member] | Fair Value [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Franchise rights measured at fair value	$ 0	$ 0