Relationship with Vornado (Details) (Vornado [member], USD $)	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	32.40%
Managment and Development Agreement [Abstract]
Management Fee Agreement Value (in US dollars)	$ 2,800,000
Leasing Agreement [Abstract]
Asset Sale Commission Threshold (in US dollars)	50,000,000
Percentage Commissions On Sale Of Assets Under Fifty Million	3.00%
Percentage Commissions On Sale Of Assets Over Fifty Million	1.00%
Leasing services fee and commission on asset sale, annual installment, maximum. (in US dollars)	4,000,000
Debt Instrument, Description of Variable Rate Basis	LIBOR
Basis spread over LIBOR	1.00%
Unpaid Balance Effective Interest	1.58%
Other Agreements [Abstract]
Other Supervisory Fees	6.00%
Summary of fees to Vornado
Fees to related party (in US dollars)	1,748,000	1,881,000
Lexington Avenue Property [Member] \| Office And Retail Space [Member]
Managment and Development Agreement [Abstract]
Property Management Fee Agreement Price Per Square Foot	0.5
Lexington Avenue Property [Member] \| Common Area [Member]
Managment and Development Agreement [Abstract]
Property Management Fee Agreement Value (in US dollars)	272,000
Property Management Fee Escalation Percentage Per Annum	3.00%
Rego Park 2 Property [Member]
Managment and Development Agreement [Abstract]
Property Management Fee Agreement Percentage Of Income	2.00%
Company Management Fees [Member]
Summary of fees to Vornado
Fees to related party (in US dollars)	700,000	700,000
Development fees [Member]
Managment and Development Agreement [Abstract]
Development fee as percentage of development costs	6.00%
Leasing Fees [Member]
Leasing Agreement [Abstract]
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%
Summary of fees to Vornado
Fees to related party (in US dollars)	178,000	386,000
Fees owed to Vornado (in US dollars)	42,102,000
Property Management Fees [Member]
Summary of fees to Vornado
Fees to related party (in US dollars)	870,000	795,000
Fees owed to Vornado (in US dollars)	$ 390,000

Asset Sale Commission Threshold

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Maximum annual installments payable for leasing services and commission on asset sales under the leasing agreement.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The fee charged to supervise cleaning, engineering and security services

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Annual amount paid to related party as property management fees

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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- Definition

Interest rate charged on unpaid commissions as of at end of the current reporting period

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The percentage charged for managing real estate properties.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 235

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.4-08.(k)(1))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph k

-Subparagraph 1

-Article 4

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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