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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

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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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