Investments in real estate, net Land undergoing predevelopment and future development (Details) - Geographical [Domain]	Jun. 30, 2015 ft²
Real Estate Properties [Line Items]
Area of Real Estate Property	18,817,923
Near-term value-creation projects in North America (CIP)
Real Estate Properties [Line Items]
Area of Real Estate Property	2,026,669.000

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration