Month and Year of ground lease expiration

No definition available.

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- Definition

Percentage Of Minimum Revenue Threshold By One Tenant.

+ References

No definition available.

+ Details

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- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611

+ Details

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- Definition

Term of the lessee's leasing arrangement renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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

The aggregate revenue from real estate operations during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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- Details

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- Details

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- Details

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Significant Tenants (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
Significant Tenants (Details) $ in Thousands	Oct. 31, 2014 ft²	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)
Real Estate Properties [Line Items]
Real estate revenue, net (in dollars)		$ 52,414	$ 50,077	$ 155,096	$ 149,528
Bloomberg [Member]
Real Estate Properties [Line Items]
Leases Expiration Date	December 2015
Bloomberg [Member] \| 731 Lexington Avenue [Member]
Real Estate Properties [Line Items]
Square Footage of Real Estate Property (in square feet) \| ft²	188,608
Lease renewal term	5 years
Bloomberg [Member] \| Customer Concentration Risk [Member]
Real Estate Properties [Line Items]
Percentage Of Minimum Revenue Threshold Contributed By One Tenant (in percentage)				10.00%
Bloomberg [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Services Net [Member]
Real Estate Properties [Line Items]
Real estate revenue, net (in dollars)				$ 70,702	$ 67,488
Percentage Rent Contributed By Tenant				45.00%	45.00%