Operating Units Investment Segment (Details) - USD ($) $ in Billions	Jun. 30, 2015	Dec. 31, 2014
Investment Funds [Member]
Segment Reporting Information [Line Items]
Fair value of our interest in Funds of subsidiary	$ 4.6	$ 4.3

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.

No definition available.

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