Fair Value Measurements - Table 1 (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Redeemable Noncontrolling Interest, Fair Value	$ 96.2	$ 121.1
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Redeemable Noncontrolling Interest, Fair Value	0.0	0.0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Redeemable Noncontrolling Interest, Fair Value	0.0	0.0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Redeemable Noncontrolling Interest, Fair Value	96.2	121.1
Other Current Assets [Member] | Restricted Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	$ 16.0	$ 16.1
Fair Value Measurements, Valuation Techniques	M	M
Other Current Assets [Member] | Restricted Marketable Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	$ 0.0	$ 0.0
Other Current Assets [Member] | Restricted Marketable Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	16.0	16.1
Other Current Assets [Member] | Restricted Marketable Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	0.0	0.0
Other Long-term Assets [Member] | Restricted Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	$ 40.7	$ 40.1
Fair Value Measurements, Valuation Techniques	M	M
Other Long-term Assets [Member] | Restricted Marketable Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	$ 0.0	$ 0.0
Other Long-term Assets [Member] | Restricted Marketable Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	40.7	40.1
Other Long-term Assets [Member] | Restricted Marketable Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Marketable Securities, Fair Value	$ 0.0	$ 0.0
Redeemable Noncontrolling Interest [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Fair Value Measurements, Valuation Techniques	I	I