Investments in Unconsolidated Real Estate Funds - Additional Information (Details)	Jun. 30, 2018
Fund VII and VII-H [Member] \| Zero Bond Street [Member]
Investment Holdings [Line Items]
Property funds, percentage	100.00%

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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