Investments in Unconsolidated Joint Ventures Business Acquisition Purchase Price table (Details) - Colorado Center [Member] - Colorado Center [Member] $ in Thousands	Jul. 01, 2016 USD ($)
Schedule of Equity Method Investments [Line Items]
Land and improvements	$ 189,597
Site improvements	9,050
Building and improvements	259,592
Tenant Improvements	17,234
In-place lease Intangibles	43,157
Above-market lease intangible	819
Below-market lease intangible	(16,461)
Net assets	$ 502,988

Amount of acquired leases acquired as part of a real property acquisition atabove market lease rate with a finite life.

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Amount of tenant improvements acquired at the acquistion date

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Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Site Improvements

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Amount of acquired leases acquired as part of a real property acquisition at below market lease rate with a finite life.

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Amount of assets acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

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Amount of facility held for productive use including, but not limited to, office, production, storage and distribution facilities, acquired at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

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Amount of real estate acquired, at the acquisition date.

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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.

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