Business Combination, Number of Acquisitions

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
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-Topic 350
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-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

+ Details

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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

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
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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- Definition

Amount of facility held for productive use including, but not limited to, office, production, storage and distribution facilities, 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)
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- Definition

Amount of real estate acquired, at the acquisition date.

+ References

+ Details

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 2
-Subparagraph (a)(1)
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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in mortgage loans on real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 310
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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
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Real Estate Acquired - Additional Information (Detail)	1 Months Ended							3 Months Ended	12 Months Ended
Real Estate Acquired - Additional Information (Detail)	Aug. 31, 2016 USD ($)	Sep. 30, 2015 USD ($)	Feb. 28, 2015 USD ($) a	Dec. 31, 2014 USD ($) property	Aug. 31, 2014 USD ($)	Apr. 30, 2014 USD ($)	Jan. 31, 2014 USD ($)	Dec. 31, 2016 USD ($) property	Dec. 31, 2016 USD ($) property	Dec. 31, 2015 USD ($) property	Dec. 31, 2014 USD ($) property
Business Acquisition [Line Items]
Aggregate cost									$ 10,300,000		$ 68,000,000
Rent expense									843,300	$ 904,900	840,800
Property acquisition costs				$ 900,000				$ 60,400	$ 60,400		$ 900,000
Number of properties acquired \| property				5				2	2	1	5
Purchase price allocated to land				$ 66,047,000				$ 9,432,000	$ 9,432,000		$ 66,047,000
Purchase price allocated to buildings				4,873,000				874,000	874,000		4,873,000
Below market lease, carrying amount								29,900,000	29,900,000	$ 29,900,000
Below market lease, accumulated amortization								15,500,000	15,500,000	13,700,000
Accretion income, intangible liabilities									1,800,000	1,800,000	1,900,000
Lease acquisition costs
Business Acquisition [Line Items]
Intangible assets gross carrying amount								24,100,000	24,100,000	24,000,000
Intangible assets, accumulated amortization								20,500,000	20,500,000	19,200,000
Amortization expense									$ 1,200,000	1,300,000	1,300,000
Weighted-average amortization period									3 years 6 months
Above Market Rent
Business Acquisition [Line Items]
Intangible assets gross carrying amount								1,000,000	$ 1,000,000	1,000,000
Intangible assets, accumulated amortization								999,700	999,700	998,200
Amortization expense									$ 1,500	1,500	22,500
Weighted-average amortization period									1 year
Below Market Leases
Business Acquisition [Line Items]
Weighted-average amortization period									5 years 10 months 24 days
1580 Rockville Pike
Business Acquisition [Line Items]
Aggregate cost							$ 8,000,000
Property acquisition costs							$ 200,000
Purchase price allocated to land				9,600,000							9,600,000
Purchase price allocated to buildings				2,200,000							2,200,000
1582 Rockville Pike
Business Acquisition [Line Items]
Aggregate cost						$ 11,000,000
Property acquisition costs						$ 200,000
Purchase price allocated to land				9,742,000							9,742,000
Purchase price allocated to buildings				828,000							828,000
1584 Rockville Pike
Business Acquisition [Line Items]
Aggregate cost				6,200,000
Property acquisition costs										200,000
Purchase price allocated to land				5,798,000							5,798,000
Purchase price allocated to buildings				440,000							440,000
750 N. Glebe Road
Business Acquisition [Line Items]
Aggregate cost					$ 40,000,000
Property acquisition costs					$ 400,000
Purchase price allocated to land				38,224,000							38,224,000
Purchase price allocated to buildings				1,327,000							1,327,000
730 N. Glebe Road
Business Acquisition [Line Items]
Aggregate cost				2,800,000
Property acquisition costs										40,400
Purchase price allocated to land				2,683,000							2,683,000
Purchase price allocated to buildings				$ 78,000							$ 78,000
726 N Glebe Road
Business Acquisition [Line Items]
Aggregate cost		$ 4,000,000								4,000,000
Property acquisition costs		$ 100,000								100,000
Purchase price allocated to land										3,900,000
Purchase price allocated to buildings										$ 100,000
700 N. Glebe Road
Business Acquisition [Line Items]
Aggregate cost	$ 7,200,000
Purchase price allocated to land								7,236,000	$ 7,236,000
Purchase price allocated to buildings								0	0
Westview Pad
Business Acquisition [Line Items]
Aggregate cost			$ 900,000
Area of real estate property (in square feet) \| a			1.1
Thruway Pad
Business Acquisition [Line Items]
Aggregate cost	3,100,000
Property acquisition costs	$ 60,000
Purchase price allocated to land								2,196,000	2,196,000
Purchase price allocated to buildings								874,000	874,000
Beacon Center
Business Acquisition [Line Items]
Aggregate cost								22,500,000
Rent expense									60,000
Mortgage loans on real estate, period increase (decrease)								11,250,000
Southdale
Business Acquisition [Line Items]
Aggregate cost								$ 15,000,000
Rent expense									$ 60,000