MORTGAGE AND OTHER NOTES PAYABLE - MORTGAGE BY PROPERTY (Details) - Jun. 30, 2015 - Mortgages - USD ($) $ in Thousands	Total
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 171,765
Repayments of long-term debt	64,976
Libor Plus 2.25% Mortgage Note \| 1035 Third Avenue
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 42,000
Description of variable rate basis	LIBOR
Libor Plus 2.25% Mortgage Note \| 1035 Third Avenue \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	2.35%
Libor Plus 1.45% Mortgage Note \| Lincoln Park Centre
Mortgage Loans on Real Estate [Line Items]
Description of variable rate basis	LIBOR
Repayments of long-term debt	$ 28,000
Libor Plus 1.45% Mortgage Note \| Lincoln Park Centre \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	1.45%
4.66% Mortgage note \| 163 Highland Avenue
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 9,765
Stated interest rate percentage	4.66%
Libor Plus 3% Mortgage Note \| Broughton Street Portfolio
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 20,000
Libor Plus 3% Mortgage Note \| Broughton Street Portfolio \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	3.00%
1.25% Mortgage Note \| City Point
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 19,000
Stated interest rate percentage	1.25%
Sifma Plus 1.6% Mortgage Note \| City Point
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 62,000
Sifma Plus 1.6% Mortgage Note \| City Point \| SIFMA
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	1.60%
Libor Plus 4% Mortgage Note \| City Point
Mortgage Loans on Real Estate [Line Items]
Repayments of long-term debt	$ 20,650
Libor Plus 4% Mortgage Note \| City Point \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	4.00%
Libor Plus 1.9% Mortgage Note \| 17 E. 71st Street
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 19,000
Libor Plus 1.9% Mortgage Note \| 17 E. 71st Street \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	1.90%
4.98% Mortgage Note \| Crescent Plaza
Mortgage Loans on Real Estate [Line Items]
Stated interest rate percentage	4.98%
Repayments of long-term debt	$ 16,326

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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