MORTGAGE AND OTHER NOTES PAYABLE - MORTGAGE BY PROPERTY (Details) - Mortgages $ in Thousands	6 Months Ended
Jun. 30, 2016 USD ($)
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 21,384
Repayments of long-term debt	272,767
Debt default, amount	26,300
LIBOR plus 1.65% Mortgage Note \| Cortlandt Town Center
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	0
Repayments of long-term debt	$ 83,070
Description of variable rate basis	LIBOR
LIBOR plus 1.65% Mortgage Note \| Cortlandt Town Center \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	1.65%
3.8% Mortgage Note \| 1964 Union Street
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 1,463
Stated interest rate percentage	3.80%
5.62% Mortgage Note \| Chicago Street Retail Portfolio
Mortgage Loans on Real Estate [Line Items]
Stated interest rate percentage	5.62%
Repayments of long-term debt	$ 14,955
LIBOR plus 1.55% Mortgage Note \| Heritage Shops
Mortgage Loans on Real Estate [Line Items]
Repayments of long-term debt	$ 24,456
Description of variable rate basis	LIBOR
LIBOR plus 1.55% Mortgage Note \| Heritage Shops \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	1.55%
LIBOR plus 1.70% Mortgage Note \| 330-340 River Street
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 12,000
Description of variable rate basis	LIBOR
LIBOR plus 1.70% Mortgage Note \| 330-340 River Street \| LIBOR
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	1.70%
5.24% Mortgage Note \| 330-340 River Street
Mortgage Loans on Real Estate [Line Items]
Stated interest rate percentage	5.24%
Repayments of long-term debt	$ 10,336
3.4% Mortgage Note \| 2208-2216 Fillmore Street
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 5,606
Stated interest rate percentage	3.40%
3.4% Mortgage Note \| 1861 Union Street
Mortgage Loans on Real Estate [Line Items]
Debt instrument face amount	$ 2,315
Stated interest rate percentage	3.40%
6.0% Mortgage Note \| Brandywine Portfolio
Mortgage Loans on Real Estate [Line Items]
Stated interest rate percentage	6.00%
Repayments of long-term debt	$ 139,950

Amount of outstanding long-term debt or borrowing associated with any securities or credit agreement for which there has been a default in principal, interest, sinking fund, or redemption provisions, or any breach of covenant that existed at the end of the period and subsequently has not been cured.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(c))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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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.

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Balance Type:	na
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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=64930739&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=64930785&loc=d3e28551-108399

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Balance Type:	credit
Period Type:	instant

- 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

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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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Balance Type:	na
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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=66902209&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

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