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Real Estate and Intangible Assets - Carrying Value of Intangible Assets and Accumulated Amortization (Detail) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
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Finite-Lived Intangible Assets [Line Items] |  |
Below market leases, gross | $ (21,606) | $ (17,951)
Below market leases, accumulated amortization | 8,959 | 8,294
Lease Intangibles [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross | 169,734 | 157,089
Finite-lived intangible assets, accumulated amortization | (64,181) | (52,175)
In-Place Leases [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross | 71,482 | 66,244
Finite-lived intangible assets, accumulated amortization | (28,182) | (22,679)
Leasing Costs [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross | 48,000 | 44,360
Finite-lived intangible assets, accumulated amortization | (18,599) | (14,774)
Customer Relationships [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross | 50,252 | 46,485
Finite-lived intangible assets, accumulated amortization | (17,400) | (14,722)
Above and Below Market Leases [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible liabilities, gross | (11,127) | (7,775)
Finite-lived intangible liabilities, accumulated amortization | 1,663 | 1,476
Above Market Leases [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross | 10,479 | 10,176
Finite-lived intangible assets, accumulated amortization | $ (7,296) | $ (6,818)

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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=26713463&loc=d3e16323-109275 + Details
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