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Real Estate Dispositions, Held for Sale, and Impairment Charges - Components of Income from Real Estate and Related Assets Held for Sale (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Real Estate Properties [Line Items] |  |  |
Impairment charge | $ 1,813,000 | $ 0 | $ 6,835,000
Real Estate Held for Sale |  |  |
Real Estate Properties [Line Items] |  |  |
Operating revenue | 600,000 | 1,167,000 | 1,156,000
Operating expense | 2,220,000 | 307,000 | 291,000
Other income, net | 323,000 | (36,000) | (240,000)
Income (expense) from real estate and related assets sold | $ (1,297,000) | $ 824,000 | $ 625,000

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- Definition Income loss from real estate and related assets held for sale. + 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=118932676&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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- Definition Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 + Details
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- Definition Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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