Affiliate Equity - Summary of Affiliate Equity Compensation (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Affiliate Equity
Affiliate equity expense	$ 30.7	$ 12.3	$ 45.9	$ 23.8
Tax benefit	4.3	2.4	7.2	5.6
Compensation expenses related to affiliate equity noncontrolling interests	19.7	5.9	27.2	9.1
Affiliate equity compensation cost not yet recognized	74.9		74.9		68.2
Affiliate equity compensation cost not yet recognized attributable to noncontrolling interest	$ 42.7		$ 42.7		$ 32.1
Period for recognition			4 years

Affiliate Equity, Compensation Cost Not yet Recognized

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Affiliate Equity, Compensation Cost Not yet Recognized Attributable to Noncontrolling Interest

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Affiliate Equity, Compensation Cost Not yet Recognized, Period for Recognition

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Affiliate Equity Compensation, Tax Benefit from Compensation Expense

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Represents the compensation expenses related to Affiliate equity.

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Compensation Expenses Related to Affiliate Equity Attributable to Noncontrolling Interest

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