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Real Estate Dispositions, Held for Sale and Impairment Charges - Additional Information (Detail) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 USD ($) property | Jun. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) property | Sep. 30, 2019 USD ($) | Dec. 31, 2019 property
Real Estate Properties [Line Items] |  |  |  |  |  |
Number of real estate properties, held for sale | 5 |  |  | 5 |  |
Number of real estate properties, held and used | 3 |  |  | 3 |  |
Impairment charge | $ | $ 1,184 |  | $ 0 | $ 2,905 | $ 0 |
Boston Heights, Ohio |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |
Number of real estate properties, held for sale | 1 |  |  | 1 |  |
Champaign, Illinois |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |
Number of real estate properties, held for sale | 3 |  |  | 3 |  |
Impairment charge | $ | $ 1,000 |  |  |  |  |
Austin, Texas |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |
Number of real estate properties, held for sale | 1 |  |  | 1 |  |
Charlotte, North Carolina |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |
Number of real estate properties, held for sale |  |  |  |  |  | 1
Blaine, Minnesota |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |
Impairment charge | $ |  | $ 1,700 |  |  |  |
Rancho Cordova, California |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |
Impairment charge | $ | $ 200 |  |  |  |  |

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- Definition Number of Impaired Assets, Held and Used + References No definition available. + Details
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
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