Investments in Unconsolidated Real Estate Funds - Schedule of Income from Fund Investment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Investment Holdings [Line Items]
Net unrealized (losses) gains	$ (132)	$ 96
Unconsolidated Real Estate Funds [Member] \| Property Fund VII [Member]
Investment Holdings [Line Items]
Investment income		185
Investment expenses	44	476
Net investment loss	(44)	(291)
Net unrealized (losses) gains	(1,879)	134
Loss from real estate fund investments	$ (1,923)	$ (157)

Equity method investment summarized financial information income (loss) from real estate fund investments.

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Equity method investment summarized financial information investment expenses.

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Equity method investment summarized financial information investment income.

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Equity method investment summarized financial information investment income (loss) net.

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Equity method investment summarized financial information unrealized gain (losses) net.

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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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