| **Redeemable Noncontrolling Interests**            | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| **Redeemable Noncontrolling Interests [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Redeemable Noncontolling Interests                 | Redeemable Noncontrolling InterestsThe following is a summary of the activity related to our Redeemable noncontrolling interests during the three months ended March 31, 2016 and 2015 (in millions): Three Months Ended March 31, 2016 2015Balance at beginning of period$121.1 $84.7Net income attributable to noncontrolling interests3.9 2.9Distributions declared(2.1) (1.7)Change in fair value(26.7) (1.2)Balance at end of period$96.2 $84.7The following table reconciles the net income attributable to nonredeemable Noncontrolling interests, as recorded in the shareholders’ equity section of the condensed consolidated balance sheets, and the net income attributable to Redeemable noncontrolling interests, as recorded in the mezzanine section of the condensed consolidated balance sheets, to the Net income attributable to noncontrolling interests presented in the condensed consolidated statements of operations for the three months ended March 31, 2016 and 2015 (in millions): Three Months Ended March 31,   2016 2015Net income attributable to nonredeemable noncontrolling interests$14.8 $13.6Net income attributable to redeemable noncontrolling interests3.9 2.9Net income attributable to noncontrolling interests$18.7 $16.5 |

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| - Definition
The entire disclosure for redeemable noncontrolling interest in consolidated subsidiaries.
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No definition available.
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| - Definition
Redeemable Noncontrolling Interests [Abstract]
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No definition available.
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