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Real Estate and Intangible Assets - Leasing Activity (Details) $ in Thousands |  | 12 Months Ended |
--- | --- | --- | ---
May 31, 2016 property | Dec. 31, 2017 USD ($) ft² property | Dec. 31, 2016 USD ($) ft² property | Dec. 31, 2015 USD ($) | Jul. 25, 2014 ft²
Real Estate Properties [Line Items] |  |  |  |  |
Aggregate Square Footage | ft² |  | 880,749 | 551,335 |  |
Annualized GAAP Rent |  | $ 6,976 | $ 2,478 |  |
Tenant Improvement |  | 1,264 | 1,244 |  |
Leasing Commissions |  | $ 742 | $ 436 |  |
Number of leased properties | property |  | 9 | 9 |  |
Tenant reimbursements |  | $ 1,988 | $ 1,489 | $ 1,753 |
Property area | ft² |  |  |  |  | 81,371
Rental revenue |  | $ 92,811 | $ 84,498 | 80,892 |
Weighted Average |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Lease Term |  | 9 years 2 months 12 days | 3 years 10 months 24 days |  |
Minimum |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Lease Term |  | 1 year | 1 year |  |
Maximum |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Lease Term |  | 11 years 3 months | 7 years 8 months 12 days |  |
Newburyport, Massachusetts [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Number of leased properties | property | 1 |  |  |  |
Tenant reimbursements |  |  | $ 900 |  |
Other Income [Member] | Newburyport, Massachusetts [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Tenant reimbursements |  |  | 300 |  |
Vance, Alabama Industrial Building |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Property area | ft² |  | 75,000 |  |  |
Buildings and improvements, gross |  | $ 6,700 |  |  |
Rental revenue |  | $ 1,800 | $ 1,200 | $ 1,200 |
Vance, Alabama Industrial Building | Maximum |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Lease Term |  | 10 years |  |  |

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- Definition Annualized straight line rent on leased property. + References No definition available. + Details
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- Definition Area of leased property. + References No definition available. + Details
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- Definition Lease term available for lease. + References No definition available. + Details
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- Definition Number of leased properties. + 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 Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 4 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6812-107765 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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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 + Details
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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 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 + Details
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