Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Property rentals	$ 38,618	$ 38,264	$ 76,859	$ 76,537
Expense reimbursements	19,635	18,926	39,274	37,882
Total revenues	58,253	57,190	116,133	114,419
Base rent
Disaggregation of Revenue [Line Items]
Property rentals	37,210	36,751	73,910	73,413
Percentage rent
Disaggregation of Revenue [Line Items]
Property rentals	0	(34)	234	163
Parking revenue
Disaggregation of Revenue [Line Items]
Property rentals	1,408	1,547	2,715	2,961
Operating expense reimbursements
Disaggregation of Revenue [Line Items]
Expense reimbursements	18,696	17,830	37,376	35,850
Tenant services
Disaggregation of Revenue [Line Items]
Expense reimbursements	$ 939	$ 1,096	$ 1,898	$ 2,032

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.

No definition available.

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- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707

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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=63488584&loc=d3e20235-122688

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- Definition

In accordance with the provisions of their lease agreement, this element represents allowable charges due a landlord from its tenant. In retail store and office building leases, for example, tenant reimbursements may cover items such as taxes, utilities, and common area expenses.

+ References

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