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Relationship with Vornado (Details) (Vornado [member], USD $) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013
Related Party Transaction [Line Items] |  |  |  |
Noncontrolling Interest, Ownership Percentage by Parent | 32.40% |  | 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% |  | 1.58% |
Other Agreements [Abstract] |  |  |  |
Other Supervisory Fees |  |  | 6.00% |
Summary of fees to Vornado |  |  |  |
Fees to related party (in US dollars) | 2,476,000 | 1,814,000 | 4,224,000 | 3,695,000
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) |  |  | 280,000 |
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 | 1,400,000 | 1,400,000
Development fees [Member] |  |  |  |
Managment and Development Agreement [Abstract] |  |  |  |
Development fee as percentage of development costs |  |  | 6.00% |
Summary of fees to Vornado |  |  |  |
Fees to related party (in US dollars) | 749,000 | 0 | 749,000 | 0
Fees owed to Vornado (in US dollars) | 749,000 |  | 749,000 |
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) | 186,000 | 292,000 | 364,000 | 678,000
Fees owed to Vornado (in US dollars) | 41,279,000 |  | 41,279,000 |
Property Management Fees [Member] |  |  |  |
Summary of fees to Vornado |  |  |  |
Fees to related party (in US dollars) | 841,000 | 822,000 | 1,711,000 | 1,617,000
Fees owed to Vornado (in US dollars) | $ 461,000 |  | $ 461,000 |

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