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Subsequent Events Narrative (Details) - Subsequent Event [Member]	Oct. 24, 2019 ft²	Oct. 01, 2019 ft² apartments
Dock 72 [Member]
Subsequent Event [Line Items]
Ownership Percentage		50.00%
Net Rentable Area (in sf)		670,000
145 Broadway [Member]
Subsequent Event [Line Items]
Net Rentable Area (in sf)	485,000
Residential Properties [Member] | The Hub on Causeway - Residential [Member]
Subsequent Event [Line Items]
Ownership Percentage		50.00%
Net Rentable Area (in sf)		320,000
Number of Units in Real Estate Property | apartments		440

X

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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X

- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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