| **Redeemable Noncontrolling Interests** | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
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| **Noncontrolling Interest [Abstract]**  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Redeemable Noncontolling Interests      | Redeemable Noncontrolling InterestsThe following is a summary of the activity related to our Redeemable noncontrolling interests during the nine months ended September 30, 2016 and 2015 (in millions): Nine Months Ended September 30, 2016 2015Balance at beginning of period$121.1 $84.7Net income attributable to noncontrolling interests11.2 10.1Distributions declared(6.4) (5.6)Change in fair value(16.5) 24.9Balance at end of period$109.4 $114.1The 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 and nine months ended September 30, 2016 and 2015 (in millions): Three Months Ended September 30,  Nine Months Ended September 30,  2016 2015 2016 2015Net income attributable to nonredeemable noncontrolling interests$12.7 $13.4 $42.5 $40.8Net income attributable to redeemable noncontrolling interests3.7 3.7 11.2 10.1Net income attributable to noncontrolling interests$16.4 $17.1 $53.7 $50.9 |

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| - Definition
The entire disclosure for noncontrolling interest in consolidated subsidiaries, which could include the name of the subsidiary, the ownership percentage held by the parent, the ownership percentage held by the noncontrolling owners, the amount of the noncontrolling interest, the location of this amount on the balance sheet (when not reported separately), an explanation of the increase or decrease in the amount of the noncontrolling interest, the noncontrolling interest share of the net Income or Loss of the subsidiary, the location of this amount on the income statement (when not reported separately), the nature of the noncontrolling interest such as background information and terms, the amount of the noncontrolling interest represented by preferred stock, a description of the preferred stock, and the dividend requirements of the preferred stock.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.31) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684
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| - References
No definition available.
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