Affiliate Equity - Summary of Affiliate Equity Compensation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Affiliate Equity [Abstract]
Affiliate equity expense	$ 40.7	$ 30.7	$ 50.0	$ 45.9
Tax benefit	$ 1.1	$ 4.3	$ 2.6	$ 7.2

Affiliate Equity Compensation, Tax Benefit from Compensation Expense

No definition available.

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