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Affiliate Equity (Tables) | 6 Months Ended
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Jun. 30, 2017
Affiliate Equity [Abstract] |
Summary of Affiliate Equity Compensation | The following is a summary of Affiliate equity expense:
| For the Three Months Ended June 30, |  | For the Six Months Ended June 30,
| 2016 |  | 2017 |  | 2016 |  | 2017
Controlling interest | $ | 2.4 |  |  | $ | 3.1 |  |  | $ | 4.5 |  |  | $ | 7.1 |
Non-controlling interests | 4.8 |  |  | 8.8 |  |  | 8.7 |  |  | 21.4 |
Total | $ | 7.2 |  |  | $ | 11.9 |  |  | $ | 13.2 |  |  | $ | 28.5 |
Summary of Affiliate Equity Unrecognized Compensation Expense [Table Text Block] | The following is a summary of unrecognized Affiliate equity expense:
| Controlling Interest |  | Remaining Life |  | Non-controlling Interests |  | Remaining Life
December 31, 2016 | $ | 31.3 |  |  | 4 years |  | $ | 70.7 |  |  | 5 years
June 30, 2017 | 32.8 |  |  | 4 years |  | 83.8 |  |  | 5 years
Schedule of Changes in the Company's Interest in its Affiliates on the Controlling Interest's Equity | While the Company presents the current redemption value of Affiliate equity within Redeemable non-controlling interests with changes in the current redemption value increasing or decreasing the controlling interest’s equity over time, the following table discloses the cumulative effect that ownership changes had on the controlling interest’s equity related only to Affiliate equity transactions that settled during the periods:
| For the Three Months Ended June 30, |  | For the Six Months Ended June 30,
| 2016 |  | 2017 |  | 2016 |  | 2017
Net income (controlling interest) | $ | 108.3 |  |  | $ | 126.3 |  |  | $ | 212.3 |  |  | $ | 248.8 |
Increase / (decrease) in controlling interest paid-in capital from purchases and sales of Affiliate equity issuances | (2.5 | ) |  | 0.9 |  |  | (3.4 | ) |  | (0.3 | )
Decrease in controlling interest paid-in capital related to Affiliate equity repurchases | (3.8 | ) |  | (16.5 | ) |  | (21.3 | ) |  | (69.1 | )
Net income attributable to controlling interest and transfers from Non-controlling interests | $ | 102.0 |  |  | $ | 110.7 |  |  | $ | 187.6 |  |  | $ | 179.4 |

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- Definition Affiliate Equity [Abstract] + References No definition available. + Details
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- Definition Represents a schedule of net income (loss) attributable to the entity and net transfers to non-controlling interest. + References No definition available. + Details
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- Definition Summary of Affiliate Equity Compensation [Table Text Block] + References No definition available. + Details
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