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Affiliate Equity (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2015 | Jun. 30, 2014 | Jun. 30, 2015 | Jun. 30, 2014 | Dec. 31, 2014
Affiliate Equity [Abstract] |  |  |  |  |
Compensation expenses related to affiliate equity noncontrolling interests | $ 37.9 | $ 19.7 | $ 43.3 | $ 27.2 |
Affiliate equity compensation cost not yet recognized | 81.3 |  | $ 81.3 |  | $ 71.1
Period for recognition |  |  | 4 years |  |
Affiliate equity compensation cost not yet recognized attributable to noncontrolling interest | $ 56.6 |  | $ 56.6 |  | $ 41.6

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