Asset sale commission threshold.

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Percentage of development costs that the related party will receive as per the Development agreement.

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No definition available.

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Lease Commission, Percentage

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No definition available.

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Percentage of rent payable to related party for leasing services for the eleventh through twentieth years of the lease.

+ References

No definition available.

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Percentage of rent payable to related party for leasing services for the first ten years of the lease.

+ References

No definition available.

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Percentage of rent payable to related party for leasing services for the twenty-first through thirtieth years of the lease.

+ References

No definition available.

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- Definition

The amount of management fee paid to related party to manage corporate activities.

+ References

No definition available.

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- Definition

Percentage of gross proceeds over $50,000,000 from the sale of any assets, payable to related party.

+ References

No definition available.

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Percentage of gross proceeds under $50,000,000 from the sale of any assets, payable to related party.

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No definition available.

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- Definition

Property Management Fee Agreement, Price Per Square Foot

+ References

No definition available.

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Annual increase in the amount paid to related party as property management fees.

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No definition available.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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Amount of liabilities classified as other.

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The amount of cash paid for commissions during the current period.

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- Definition

The percentage charged for managing real estate properties.

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- Definition

Amount of transactions with related party during the financial reporting period.

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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.

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Related Party Transactions - Narrative (Details)	3 Months Ended			9 Months Ended
Related Party Transactions - Narrative (Details)	Sep. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) $ / ft²	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Related Party Transaction [Line Items]
Fees to related party	$ 2,720,000		$ 2,302,000	$ 10,432,000	$ 7,493,000
Development fees
Related Party Transaction [Line Items]
Fees to related party	0		182,000	144,000	808,000
Leasing fees
Related Party Transaction [Line Items]
Fees to related party	633,000		303,000	1,155,000	545,000
Property management, cleaning, engineering, parking and security fees
Related Party Transaction [Line Items]
Fees to related party	1,387,000		$ 1,117,000	4,678,000	$ 4,040,000
Related Party
Related Party Transaction [Line Items]
Management fee agreement value				2,800,000
Other liabilities	1,359,000			$ 1,359,000		$ 134,000
Related Party \| Rego Park I property
Related Party Transaction [Line Items]
Payments for commissions		$ 2,355,000
Related Party \| Development fees
Related Party Transaction [Line Items]
Development fee as percentage of development costs				6.00%
Other liabilities						34,000
Related Party \| Leasing fees
Related Party Transaction [Line Items]
Lease fee percentage of rent one to ten years				3.00%
Lease fee percentage of rent eleven to twenty years				2.00%
Lease fee percentage of rent twenty first to thirty years				1.00%
Percentage of third-party lease commission				33.333%
Percentage commissions on sale of assets under fifty million				3.00%
Asset sale commission threshold				$ 50,000,000
Percentage commissions on sale of assets over fifty million				1.00%
Other liabilities	633,000			$ 633,000		$ 100,000
Related Party \| Property management, cleaning, engineering, parking and security fees
Related Party Transaction [Line Items]
Other liabilities	$ 726,000			$ 726,000
Related Party \| Retail Space \| Rego Park Shopping Center \| Property management fees
Related Party Transaction [Line Items]
Property management fee, percent fee				2.00%
Related Party \| Office and Retail Space \| 731 Lexington Avenue \| Property management fees
Related Party Transaction [Line Items]
Property management fee agreement, price per square foot \| $ / ft²				0.50
Related Party \| Common Area \| 731 Lexington Avenue \| Property management fees
Related Party Transaction [Line Items]
Property management fee escalation percentage per annum				3.00%
Related Party \| Common Area \| 731 Lexington Avenue \| Management and development agreement, base management fee
Related Party Transaction [Line Items]
Fees to related party				$ 399,000
Vornado \| Leasing fees
Related Party Transaction [Line Items]
Asset sale commission threshold				$ 50,000,000
Alexander's Inc. \| Related Party \| Vornado
Related Party Transaction [Line Items]
Subsidiary, ownership percentage, parent	32.40%			32.40%