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v3.23.2

Related Party Transactions - Additional Information (Detail) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) $ / ft² | Jun. 30, 2022 USD ($) | Dec. 31, 2022 USD ($)
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, amounts of transaction | $ 3,090,000 | $ 2,247,000 | $ 5,240,000 | $ 5,537,000 |
Amounts due to Vornado | 952,000 |  | 952,000 |  | $ 801,000
Management And Development Agreement, Base Management Fee | 731 Lexington Avenue | Common Area |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, amounts of transaction |  |  | $ 365,000 |  |
Leasing and Other Agreements, Percentage of Gross Proceeds Used for Commission for Sales Less Than Fifty Million |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, rate |  |  | 3.00% |  |
Asset sale commission threshold |  |  | $ 50,000,000 |  |
Leasing and Other Agreements, Percentage of Gross Proceeds Used For Commission for Sales Greater Than Fifty Million |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, rate |  |  | 1.00% |  |
Asset sale commission threshold |  |  | $ 50,000,000 |  |
Leasing fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, amounts of transaction | 129,000 | $ 0 | 170,000 | $ 1,318,000 |
Related Party | Rego Park III Land Parcel |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Payments for commissions | 711,000 |  |  |  |
Related Party | Management and Development Agreement |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Annual management fee |  |  | $ 2,800,000 |  |
Related Party | Management and Development Agreement | 731 Lexington Avenue | Office and Retail Space |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Property management fee agreement, price per square foot | $ / ft² |  |  | 0.50 |  |
Related Party | Management and Development Agreement, Percentage of Gross Revenue | Rego Park II | Retail Space |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Property management fee agreement percentage of annual escalation |  |  | 2.00% |  |
Related Party | Management and Development Agreement, Annualized Management Fee | 731 Lexington Avenue | Common Area |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Property management fee agreement percentage of annual escalation |  |  | 3.00% |  |
Related Party | Management and Development Agreement, Development Fee |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Property management fee agreement percentage of annual escalation |  |  | 6.00% |  |
Related Party | Leasing and Other Agreements, Percentage of Rent for First Ten Years |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Service fees, rate |  |  | 3.00% |  |
Related Party | Leasing and Other Agreements, Percentage of Rent for Eleventh Through Twentieth Year |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Service fees, rate |  |  | 2.00% |  |
Related Party | Leasing and Other Agreements, Percentage of Rent for the Twenty-First Through the Thirtieth Year |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Service fees, rate |  |  | 1.00% |  |
Related Party | Leasing and Other Agreements, Percentage Increase in Fee if Third Party is Used |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Service fees, rate |  |  | 1.00% |  |
Related Party | Management, property management, cleaning, engineering and security fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Amounts due to Vornado | 823,000 |  | $ 823,000 |  | 742,000
Related Party | Leasing fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Amounts due to Vornado | $ 129,000 |  | $ 129,000 |  | $ 59,000
Vornado | Alexander's Inc. | Related Party |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Ownership percentage by noncontrolling owners | 32.40% |  | 32.40% |  |

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