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Commitments and Contingencies (Litigation and contingencies) (Details) ft² in Thousands, $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 USD ($) | Feb. 28, 2014 fire | Dec. 31, 2021 USD ($) ft²
Commitments And Contingencies Disclosure |  |  |
Standby letters of credit, outstanding |  |  | $ 960
Rego Park I | Sears |  |  |
Commitments And Contingencies Disclosure |  |  |
Area of land | ft² |  |  | 195
Number of fires | fire |  | 2 |
Minimum | Rego Park I | Sears |  |  |
Commitments And Contingencies Disclosure |  |  |
Loss contingency, damages sought, value |  |  | $ 4,000
Estimated Future Damages | Rego Park I | Sears |  |  |
Commitments And Contingencies Disclosure |  |  |
Loss contingency, damages sought, value | $ 650 |  |
Estimated Future Damages | Minimum | Rego Park I | Sears |  |  |
Commitments And Contingencies Disclosure |  |  |
Loss contingency, damages sought, value |  |  | 25,000
Estimated Future Damages | Maximum | Rego Park I | Sears |  |  |
Commitments And Contingencies Disclosure |  |  |
Loss contingency, estimate of possible loss |  |  | $ 650

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