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Real Estate Dispositions, Held for Sale and Impairment Charges - Additional Information (Detail) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2021 USD ($) property | Jun. 30, 2020 USD ($) tenant | Dec. 31, 2020 property
Real Estate Properties [Line Items] |  |  |
Number of real estate properties, held for sale | 0 |  |
Impairment charge | $ | $ 0 | $ 1,700,000 |
Boston Heights, Ohio; Rancho Cordova, California; Champaign, Illinois |  |  |
Real Estate Properties [Line Items] |  |  |
Number of real estate properties, held for sale |  |  | 3
Rancho Cordova, California and Champaign, Illinois |  |  |
Real Estate Properties [Line Items] |  |  |
Number of properties sold | 2 |  |
Blaine, Minnesota |  |  |
Real Estate Properties [Line Items] |  |  |
Number of properties impaired | tenant |  | 1 |

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- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). + 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=123570139&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230 Reference 3: 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=123351718&loc=d3e2420-110228 + Details
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