Affiliate Equity - Summary of Affiliate Equity Compensation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Affiliate Equity [Abstract]
Affiliate equity expense	$ 9.2	$ 14.1	$ 59.2	$ 60.0
Tax benefit	$ 1.3	$ 2.4	$ 3.9	$ 9.6

Affiliate Equity Compensation, Tax Benefit from Compensation Expense

No definition available.

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