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Relationship with Vornado (Details) (Vornado [member], USD $) | 3 Months Ended
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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 |

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