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Schedule II Valuation and qualifying accounts (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Allowance for doubtful accounts - Tenant rent receivables |  |  |
Movement in valuation and qualifying accounts |  |  |
Balance at beginning of year | $ 17,000 | $ 533,000 | $ 505,000
Additions (Decreases) charged to costs and expenses | (9,000) | (38,000) | 157,000
Deductions |  | (478,000) | (129,000)
Balance at end of year | 8,000 | 17,000 | $ 533,000
Allowance for doubtful accounts - Allowance for credit losses |  |  |
Movement in valuation and qualifying accounts |  |  |
Balance at beginning of year | 4,237,000 |  |
Additions (Decreases) charged to costs and expenses | $ (4,237,000) | 4,237,000 |
Balance at end of year |  | $ 4,237,000 |

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- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column B)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-4 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column E)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-4 + Details
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- Definition Amount of decrease in valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column D)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-4 + Details
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