Asset Acquisition, Capitalized Transaction Costs

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- Definition

Number Of Buildings Acquired

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- Definition

Number Of Joint Ventures

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- Definition

Number Of Properties Acquired

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No definition available.

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- Definition

Represents the percentage of property leased.

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No definition available.

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- Definition

Represents the amount of purchase price allocated to building and building improvements.

+ References

No definition available.

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- Definition

Represent the value of other assumed assets.

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No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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- Definition

Amount of real estate acquired, at the acquisition date.

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- Definition

Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

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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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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash outflow from the acquisition of a piece of land and anything permanently fixed to it, including buildings, structures on it and so forth, and payments to develop real estate assets by adding improvements on or to a parcel of land. Such improvements may include drainage, utilities, subdividing, access, buildings, and any combination of these elements. Including real estate intended to generate income for the owner; excluding real estate acquired for use by the owner.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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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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Real Estate Properties - Acquisition Activities (Details) $ in Thousands		1 Months Ended		9 Months Ended
	Oct. 02, 2017 USD ($) ft² property joint_venture building	Sep. 30, 2017 USD ($) ft² property	Jan. 31, 2017 USD ($) ft² property building	Sep. 30, 2017 USD ($) ft² property building	Sep. 30, 2016 USD ($)
Real Estate Properties [Line Items]
Purchase price				$ 666,202	$ 83,705
Manassas, VA
Real Estate Properties [Line Items]
Number of properties \| property		1	1	1
Number of buildings acquired \| building			1	1
Rentable square feet of properties (in square feet) \| ft²		69,374	69,374	69,374
Percentage of property leased				100.00%
Purchase price			$ 12,657	$ 12,657
Capitalized acquisition costs		$ 37		$ 37
Land			1,562
Buildings and Improvement			8,253
Other assumed assets			$ 2,842
Transferable Development Rights \| Washington D.C.
Real Estate Properties [Line Items]
Consideration transferred		$ 2,030
Subsequent Event \| First Potomac Realty Trust
Real Estate Properties [Line Items]
Number of properties \| property	39
Number of buildings acquired \| building	74
Rentable square feet of properties (in square feet) \| ft²	6,454,382
Consideration transferred	$ 1,374,624
Number of joint ventures \| joint_venture	2
Cash consideration paid	$ 651,696
Expected repayment of debt	$ 483,000
Subsequent Event \| First Potomac Realty Trust
Real Estate Properties [Line Items]
Number of joint ventures \| joint_venture	2
Subsequent Event \| Joint Venture Property 1 \| First Potomac Realty Trust
Real Estate Properties [Line Items]
Ownership percentage	50.00%
Subsequent Event \| Joint Venture Property 2 \| First Potomac Realty Trust
Real Estate Properties [Line Items]
Ownership percentage	51.00%
FPO Mortgage \| Mortgage \| Subsequent Event \| First Potomac Realty Trust
Real Estate Properties [Line Items]
Mortgage debt assumed	$ 167,549
Joint Venture Mortgage \| Mortgage \| Subsequent Event \| First Potomac Realty Trust
Real Estate Properties [Line Items]
Mortgage debt assumed	$ 82,000