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Real Estate and Intangible Assets - Additional Information (Detail) $ in Thousands |  | 12 Months Ended
--- | --- | ---
May 31, 2016 property | Dec. 31, 2016 USD ($) property | Dec. 31, 2015 USD ($) property | Dec. 31, 2014 USD ($)
Real Estate Properties [Line Items] |  |  |  |
Number of properties acquired | property |  | 3 | 6 |
Number of leased properties | property |  | 9 | 15 |
Tenant reimbursements |  | $ 1,489 | $ 1,753 | $ 2,079
Total amortization expense related to lease intangible assets |  | 13,400 | 13,100 | 10,100
Amortization related to below-market lease |  | 1,200 | 900 | 700
Above Market Leases [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Amortization related to above-market lease |  | 500 | $ 400 | $ 300
Newburyport, Massachusetts [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Number of leased properties | property | 1 |  |  |
Tenant reimbursements |  | 900 |  |
Newburyport, Massachusetts [Member] | Other Income [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Tenant reimbursements |  | $ 300 |  |

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- Definition Number of leased properties. + References No definition available. + Details
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- Definition Number of properties acquired. + References No definition available. + Details
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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. + Details
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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 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition The expense charged against earnings for the periodic recognition of capitalized leases. This element may apply to energy companies that lease mineral producing properties and to other enterprises that capitalize property, plant, or equipment obtained through capital leases. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45031-112735 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + 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 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=26872669&loc=d3e20235-122688 + Details
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- Details
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- Details
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