Related Party Transactions - Due from Affiliates and Other Receivables (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Notes receivable and accrued interest from affiliates	$ 20.8	$ 11.1
Other receivables from unconsolidated funds and affiliates, net	153.9	160.6
Total	205.1	199.4
Contingent Obligations (Giveback)
Related Party Transaction [Line Items]
Unbilled receivable for giveback obligations from current and former employees	$ 30.4	$ 27.7

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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