Real Estate Fund Investments - Additional Information (Details)	Sep. 30, 2016
Property Fund II [Member]
Investment Holdings [Line Items]
Percentage interest in fund	10.00%
Property Fund III [Member]
Investment Holdings [Line Items]
Percentage interest in fund	3.10%
Property Fund VII [Member]
Investment Holdings [Line Items]
Percentage interest in fund	7.50%

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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