Organization and Basis (Details)	12 Months Ended
	Dec. 31, 2011 sqft
731 Lexington Avenue Property
Operating Properties [Abstract]
Total area of property	1,307,000
731 Lexington Avenue Property | Office Space [Member]
Operating Properties [Abstract]
Total area of property	885,000
731 Lexington Avenue Property | Office Space [Member] | Tenant Occupant [Member] | Bloomberg [Member]
Operating Properties [Abstract]
Total area of property	885,000
731 Lexington Avenue Property | Retail Space [Member]
Operating Properties [Abstract]
Total area of property	174,000
731 Lexington Avenue Property | Retail Space [Member] | Tenant Occupant [Member] | Container Store [Member]
Operating Properties [Abstract]
Total area of property	34,000
731 Lexington Avenue Property | Retail Space [Member] | Tenant Occupant [Member] | Hennes Mauritz [Member]
Operating Properties [Abstract]
Total area of property	27,000
731 Lexington Avenue Property | Retail Space [Member] | Tenant Occupant [Member] | Home Depot [Member]
Operating Properties [Abstract]
Total area of property	83,000
731 Lexington Avenue Property | Residential Space [Member]
Operating Properties [Abstract]
Total area of property	248,000
Number Of Residential Units Sold	105
The Kings Plaza Regional Shopping Center
Operating Properties [Abstract]
Total area of property	1,210,000
The Kings Plaza Regional Shopping Center | Owner Occupant [Member] | Macys [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	339,000
The Kings Plaza Regional Shopping Center | Tenant Occupant [Member] | Sears [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	289,000
The Kings Plaza Regional Shopping Center | Tenant Occupant [Member] | Lowes [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	114,000
Rego Park I Shopping Center
Operating Properties [Abstract]
Total area of property	343,000
Rego Park I Shopping Center | Tenant Occupant [Member] | Burlington Coat Factory [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	50,000
Rego Park I Shopping Center | Tenant Occupant [Member] | Marshalls [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	36,000
Rego Park I Shopping Center | Tenant Occupant [Member] | Bed Bath Beyond [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	46,000
Rego Park I Shopping Center | Tenant Occupant [Member] | Sears [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	195,000
Rego Park II Property
Operating Properties [Abstract]
Total area of property	610,000
Rego Park II Property | Tenant Occupant [Member] | Toys R Us [Member]
Operating Properties [Abstract]
Total area of property	47,000
Related Party Ownership In Tenant	one-third
Rego Park II Property | Tenant Occupant [Member] | Kohls [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	133,000
Rego Park II Property | Tenant Occupant [Member] | Century 21 [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	135,000
Rego Park II Property | Tenant Occupant [Member] | Costco [Member] | Anchor [Member]
Operating Properties [Abstract]
Total area of property	145,000
The Paramus Property | Tenant Occupant [Member] | Ikea [Member]
Operating Properties [Abstract]
Acres Of Real Estate Land	30.3
The Flushing Property | Tenant Occupant [Member] | New World Mall Llc [Member]
Operating Properties [Abstract]
Total area of property	167,000
The Rego Park III Property | Property To Be Developed [Member]
Operating Properties [Abstract]
Acres Of Real Estate Land	3.4