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Afilliate Equity - Schedule of the Effect of Changes in the Company's Ownership Interest in its Affiliates on the Controlling Interest's Equity (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
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Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Affiliate Equity [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net income (controlling interest) | $ 150.2 | $ 110.2 | $ 108.3 | $ 104.0 | $ 147.5 | $ 107.7 | $ 127.6 | $ 126.7 | $ 472.8 | $ 509.5 | $ 433.9
Increase in controlling interest paid-in capital from purchases and sales of Affiliate equity issuances |  |  |  |  |  |  |  |  | 1.6 | 0.9 | 4.1
Decrease in controlling interest paid-in capital related to Affiliate equity repurchases |  |  |  |  |  |  |  |  | (38.0) | (87.6) | (33.2)
Net income attributable to controlling interest and transfers (to) or from Non-controlling interests |  |  |  |  |  |  |  |  | $ 436.4 | $ 422.8 | $ 404.8

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- Definition Adjustments to Additional Paid in Capital Decrease in Carrying Amount of Redeemable Noncontrolling Interests + References No definition available. + Details
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- Definition Adjustments to Additional Paid in Capital Increase in Carrying Amount of Redeemable Noncontrolling Interests + References No definition available. + Details
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- Definition Affiliate Equity [Abstract] + References No definition available. + Details
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- Definition Increase (decrease) in equity during the period due to net income attributable to the parent company and net transfers with non-controlling interests. + References No definition available. + Details
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=51831255 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=51831270 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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