INVESTMENTS IN REAL ESTATE (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Real Estate [Abstract]
Land	$ 343,564	$ 363,612
Land improvements	26,177	26,747
Buildings and improvements	1,475,415	1,506,962
Furniture, fixtures, and equipment	4,955	9,720
Tenant improvements	159,677	146,205
Work in progress	11,706	8,126
Investments in real estate	2,021,494	2,061,372
Accumulated depreciation	(414,552)	(369,661)
Net investments in real estate	1,606,942	1,691,711
Depreciation expense	$ 62,239	$ 61,915	$ 58,635

The expense recognized in the current period that allocates the cost of a tangible asset used in providing revenue generating services over the asset's useful life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(d))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

The current amount of expenditures for a real estate project that has not yet been completed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.10)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Phase
-URI http://asc.fasb.org/extlink&oid=49177889

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- Definition

Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

+ References

No definition available.

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- Definition

Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

+ References

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount before accumulated deprecation and depletion of additions or improvements to real estate held for productive use. Examples include, but are not limited to, walkways, driveways, fences, and parking lots.

+ References

No definition available.

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- References

No definition available.

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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

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- Definition

Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

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