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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

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- Definition Affiliate Equity [Abstract] + References No definition available. + Details
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- Definition Affiliate Equity Compensation, Tax Benefit from Compensation Expense + References No definition available. + Details
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- Definition Represents the compensation expenses related to Affiliate equity. + References No definition available. + Details
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