Related Party Transactions - Additional Information (Detail) ft² in Thousands, $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($) ft² $ / ft²	Dec. 31, 2017 USD ($)
Related Party Transaction [Line Items]
Receivable arising from the straight-lining of rents	$ 169,124	$ 174,713
Toys R Us
Related Party Transaction [Line Items]
Receivable arising from the straight-lining of rents	$ 500
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
Vornado
Related Party Transaction [Line Items]
Noncontrolling interest, ownership percentage by noncontrolling owners	32.40%
Management fee agreement value	$ 2,800
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
Percentage commissions on sale of assets over fifty million	1.00%
Amount Due to / (Fees paid to) related party	$ 13	1,811
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 \| 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
Property management fee escalation percentage per annum	3.00%
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	$ 47	21
Vornado \| Management, Property Management, Cleaning, Engineering and Security Fees
Related Party Transaction [Line Items]
Amount Due to / (Fees paid to) related party	381	$ 658
Tenant Improvements \| Toys R Us
Related Party Transaction [Line Items]
Depreciation and amortization	588
Deferred Leasing Costs \| Toys R Us
Related Party Transaction [Line Items]
Depreciation and amortization	$ 215
Vornado \| Vornado \| Toys R Us
Related Party Transaction [Line Items]
Noncontrolling interest, ownership percentage by parent	32.50%

Annual revenue attributable to tenant.

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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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- Definition

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.

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

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- Definition

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

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- Definition

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

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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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Percentage of increase in leasing services payable to related party if a real estate broker is used

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Amount per square foot paid to related party as property management fees.

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Annual amount paid to related party as property management fees.

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- Definition

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

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- Definition

Area of a real estate property.

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- Definition

The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property, by the lessor or lessee, respectively. Such receivable is reduced by allowances attributable to, for instance, credit risk associated with a lessee.

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- Definition

The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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

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The percentage charged for managing real estate properties.

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Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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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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