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Commitments and Contingencies - Additional Information (Detail) ft² in Thousands | 1 Months Ended | 9 Months Ended
--- | --- | ---
Mar. 31, 2016 USD ($) | Jun. 30, 2014 USD ($) ft² | Feb. 28, 2014 fire | Sep. 30, 2021 USD ($)
Loss Contingencies [Line Items] |  |  |  |
Standby letters of credit, outstanding |  |  |  | $ 960,000
Rego Park I | Sears |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Area of property (in sqft.) | ft² |  | 195 |  |
Number of fires | fire |  |  | 2 |
Rego Park I | Sears | Estimated Future Damages |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, damages sought, value | $ 650,000 |  |  |
Rego Park I | Sears | Minimum |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, damages sought, value |  | $ 4,000,000 |  |
Rego Park I | Sears | Minimum | Estimated Future Damages |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, damages sought, value |  | $ 25,000,000 |  |
Rego Park I | Sears | Maximum | Estimated Future Damages |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Reasonably possible losses |  |  |  | 650,000
All Risk Property and Rental Value |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Insurance maximum coverage per occurrence |  |  |  | 1,700,000,000
Terrorism Coverage Including NBCR |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Insurance maximum coverage per occurrence |  |  |  | 1,700,000,000
Insurance maximum coverage in aggregate |  |  |  | $ 1,700,000,000
NBCR |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Federal government responsibility |  |  |  | 80.00%
NBCR | FNSIC |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Insurance deductible |  |  |  | $ 275,000
Self insured responsibility |  |  |  | 20.00%
General Liability |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Insurance maximum coverage per occurrence |  |  |  | $ 300,000,000
Insurance maximum coverage per property |  |  |  | 300,000,000
Disease Coverage |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Insurance maximum coverage per occurrence |  |  |  | $ 30,000,000

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