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Related Party Transactions - Additional Information (Detail) ft² in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 USD ($) $ / ft² | Dec. 31, 2018 USD ($) ft²
Rego Park II | Retail Space | Toys R Us |  |
Related Party Transaction [Line Items] |  |
Area of property | ft² |  | 47
Annual revenue from leased property |  | $ 2,600,000
Vornado |  |
Related Party Transaction [Line Items] |  |
Noncontrolling interest, ownership percentage by noncontrolling owners | 32.40% |
Management fee agreement value | $ 2,800,000 |
Vornado | Toys R Us |  |
Related Party Transaction [Line Items] |  |
Noncontrolling interest, ownership percentage by parent |  | 32.50%
Vornado | Property management, cleaning, engineering and security fees | 731 Lexington Avenue | Office and Retail Space |  |
Related Party Transaction [Line Items] |  |
Property management fee agreement price per square foot | $ / ft² | 0.50 |
Vornado | Property management, cleaning, engineering and security fees | 731 Lexington Avenue | Common Area |  |
Related Party Transaction [Line Items] |  |
Property management fee agreement value | $ 315,000 |
Property management fee escalation percentage per annum | 3.00% |
Vornado | Property management, cleaning, engineering and security fees | Rego Park II | Retail Space |  |
Related Party Transaction [Line Items] |  |
Property management fee agreement percentage of income | 2.00% |
Vornado | 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 increase lease fee if broker used | 1.00% |
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% |
Amount Due to / (Fees paid to) related party | $ (729,000) | $ (13,000)
Vornado | Development fees |  |
Related Party Transaction [Line Items] |  |
Development fee as percentage of development costs | 6.00% |
Amount Due to / (Fees paid to) related party | $ (170,000) | (146,000)
Vornado | Management, Property Management, Cleaning, Engineering and Security Fees |  |
Related Party Transaction [Line Items] |  |
Amount Due to / (Fees paid to) related party | $ (543,000) | $ (549,000)

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