Fair Value Measurements and the Fair Value Option - Unconsolidated Investments (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Equity Method Investments [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
FV Option		$ 61.0
Equity Method Investments [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total	$ 206.1	$ 85.9

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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