Real Estate Fund Investments - Summary of Fair Value of Fund Investments and Income from Fund Investments (Parenthetical) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Investment Holdings [Line Items]
Asset management fee income	$ 1,714
Noncontrolling Interest [Member]
Investment Holdings [Line Items]
Asset management fee income		$ 1,334

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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