The Alexander Apartment Tower (Details) - Rego Park II [Member] - Operating Property [Member] - The Alexander apartment tower [Member] ft² in Thousands	9 Months Ended
Sep. 30, 2016 ft² aptunits
Real Estate Properties [Line Items]
Number of units in real estate property (in units) \| aptunits	312
Percenatage of property leased	97.40%
Area of property (in square feet) \| ft²	255

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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