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Business Combinations - Schedule of Unaudited Pro Forma Financial Results (Details) - Baker Street Advisors, LLC and myCIO Wealth Partners, L.P. - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014
Business Acquisition |  |
Revenue | $ 2,499.4 | $ 2,538.2
Net income (controlling interest) | $ 517.9 | $ 454.5
Earnings per share—basic (in dollars per share) | $ 9.53 | $ 8.26
Earnings per share—diluted (in dollars per share) | $ 9.31 | $ 8.05

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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
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