number of buildings

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- Definition

Term of Lease Signed (in years)

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- Definition

Vehicles In Structured Parking

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- Definition

Area of land held.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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Net rentable area for properties owned.

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The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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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.

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Subsequent Events subsequent Events (Details) $ in Thousands		6 Months Ended
	Jul. 28, 2017 USD ($) ft² a Buildings Vehicles	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jul. 26, 2017 ft² yr
Subsequent Event [Line Items]
Proceeds from mortgage notes payable \| $		$ 2,300,000	$ 0
Colorado Center [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Ownership Percentage	50.00%
number of buildings \| Buildings	6
Area of Land \| a	15
Net Rentable Area (in sf) \| ft²	1,184,000
Vehicles In Structured Parking \| Vehicles	3,100
7750 Wisconsin Avenue [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Ownership Percentage				50.00%
Net Rentable Area (in sf) \| ft²				720,000
Term of Lease Signed (in years) \| yr				20
Secured Debt [Member] \| Colorado Center [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Debt Instrument, Term	10 years
Proceeds from mortgage notes payable \| $	$ 550,000
Coupon/Stated Rate	3.56%
Parent Company [Member] \| 7750 Wisconsin Avenue [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Ownership Percentage				50.00%