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Real Estate and Intangible Assets - Carrying Value of Intangible Assets and Accumulated Amortization (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Finite-Lived Intangible Assets [Line Items] |  |
Below market leases and deferred revenue, gross | $ (36,365) | $ (34,322)
Below market leases and deferred revenue, accumulated amortization | 15,686 | 15,000
Lease Intangibles |  |
Finite-Lived Intangible Assets [Line Items] |  |
Lease Intangibles | 238,166 | 226,525
Accumulated Amortization | (116,130) | (111,060)
In-place leases |  |
Finite-Lived Intangible Assets [Line Items] |  |
Lease Intangibles | 97,348 | 92,906
Accumulated Amortization | (50,602) | (48,468)
Leasing costs |  |
Finite-Lived Intangible Assets [Line Items] |  |
Lease Intangibles | 73,231 | 68,256
Accumulated Amortization | (35,240) | (33,705)
Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Lease Intangibles | 67,587 | 65,363
Accumulated Amortization | (30,288) | (28,887)
Above market leases and below market leases and deferred revenue |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets (liabilities), gross | (21,547) | (17,820)
Finite-lived intangible assets (liabilities), accumulated amortization | 5,574 | 4,995
Above market leases |  |
Finite-Lived Intangible Assets [Line Items] |  |
Lease Intangibles | 14,818 | 16,502
Accumulated Amortization | $ (10,112) | $ (10,005)

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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/disclosureRef -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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