Contractual Sales Price

No definition available.

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- Definition

Number of parcels of land.

+ References

No definition available.

+ Details

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- Definition

Number of real estate properties interests disposed of.

+ References

No definition available.

+ Details

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- Definition

The number of real estate properties sold during the period.

+ References

No definition available.

+ Details

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- Definition

Purchase and sales agreement date.

+ References

No definition available.

+ Details

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- Definition

Expected hold period for assets held for use, used as an input to measure fair value

+ References

No definition available.

+ Details

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- Definition

Ratio of the net operating income produced by an asset and its capital cost (original prices paid to buy the asset), used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

+ Details

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2611-110228

Reference 2: 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=98514028&loc=d3e3602-108585

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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

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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Data Type:	num:areaItemType
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- Details

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- Details

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Real Estate Investments - Summary of Properties Classified as Held for Sale Included in Continuing Operations (Parenthetical) (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2016 property	Dec. 31, 2015 USD ($)	Feb. 04, 2016 property	Jan. 15, 2016 USD ($) Parcel	Dec. 23, 2015 ft²
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of Real Estate Properties \| property				58
Och Ziff Properties [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Provision for impairment on assets held for sale			$ 45,400,000
2970 Market Street (Cira Square) [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Provision for impairment on assets held for sale			$ 0
Purchase and Sale Agreement Date			Dec. 23, 2015
Rentable Square Feet \| ft²						862,692
Greenhills Land [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Provision for impairment on assets held for sale			$ 300,000
Number of Parcels \| Parcel					120
Contractual Sales Price					$ 900,000
Held for Sale Properties Included in Continuing Operations [Member] \| Metropolitan D.C. - Office [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of Properties Sold \| property		3
Provision for impairment on assets held for sale	$ 3,000,000
Impairment Hold Period		10 years
Residual Capitalization Rates		9.00%
Discount Rates		10.00%
Held for Sale Properties Included in Continuing Operations [Member] \| Other Segment - Office [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of Properties Sold \| property		2
Provision for impairment on assets held for sale	$ 11,500,000
Impairment Hold Period		10 years
Residual Capitalization Rates		9.75%
Discount Rates		9.75%