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Real Estate and Intangible Assets - Carrying Value of Intangible Assets and Accumulated Amortization (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items] |  |  |
Below market leases, gross | $ (26,725) | $ (21,606) |
Below market leases, accumulated amortization | 10,475 | 8,959 |
Amortization of intangible assets | 15,900 | 13,400 | $ 13,100
Amortization of below market lease | 1,500 | 1,200 | 900
Lease Intangibles [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-lived intangible assets, gross | 194,942 | 169,734 |
Finite-lived intangible assets, accumulated amortization | (76,015) | (64,181) |
In-Place Leases |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-lived intangible assets, gross | 80,355 | 71,482 |
Finite-lived intangible assets, accumulated amortization | (33,201) | (28,182) |
Leasing Costs |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-lived intangible assets, gross | 55,695 | 48,000 |
Finite-lived intangible assets, accumulated amortization | (23,016) | (18,599) |
Customer Relationships |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-lived intangible assets, gross | 58,892 | 50,252 |
Finite-lived intangible assets, accumulated amortization | (19,798) | (17,400) |
Above and Below Market Leases [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-lived intangible liabilities, gross | (12,300) | (11,127) |
Finite-lived intangible liabilities, accumulated amortization | 2,513 | 1,663 |
Above Market Leases |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-lived intangible assets, gross | 14,425 | 10,479 |
Finite-lived intangible assets, accumulated amortization | (7,962) | (7,296) |
Amortization of leased asset | $ 700 | $ 500 | $ 400

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- Definition Finite lived intangible assets (liabilities) accumulated amortization. + References No definition available. + Details
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- Definition Finite lived intangible assets (liabilities) gross. + 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=98514028&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=66006027&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=84164758&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=98514028&loc=d3e3602-108585 + 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 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 -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before 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 -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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