v2.4.0.8
Noncontrolling Interests (Property Partnerships) (Narrative) (Details) (USD $)
9 Months Ended 0 Months Ended 9 Months Ended 0 Months Ended 0 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Dec. 31, 2013
May 31, 2013
767 Fifth Avenue (The GM Building) [Member]
Consolidated Properties [Member]
Apr. 10, 2014
Salesforece Tower (formerly Transbay Tower) [Member]
Consolidated Properties [Member]
sqft
Sep. 30, 2013
Noncontrolling Interests [Member]
May 31, 2013
Noncontrolling Interests [Member]
Consolidated Properties [Member]
partners
Oct. 09, 2013
Noncontrolling Interests [Member]
Time Square Tower [Member]
Consolidated Properties [Member]
sqft
Feb. 26, 2013
Noncontrolling Interests [Member]
Salesforece Tower (formerly Transbay Tower) [Member]
Consolidated Properties [Member]
Feb. 07, 2014
Noncontrolling Interests [Member]
Salesforece Tower (formerly Transbay Tower) [Member]
Consolidated Properties [Member]
Noncontrolling Interest [Line Items]                    
Property partnerships $ 716,565,000   $ 726,132,000              
Partners Joint Venture Ownership Percentage       40.00%            
Ownership Percentage               45.00% 5.00% 50.00%
Sales price               684,000,000    
Ownership Percentage by Parent         95.00%       95.00%  
Number of Joint Venture Partners             2      
Noncontrolling interests recorded upon consolidation 0 480,861,000   480,900,000   480,861,000        
maximum percentage of construction costs to allow partner to have a loan                 50.00%  
Portion of total costs partner can require the company to fund                 2.50%  
portion of partners equity that can be funded by the company                 50.00%  
Proceeds from sale of an interest in a real estate asset               673,100,000    
Area of Real Estate Property         1,400,000     1,246,000    
Portion allocation to noncontrolling interest based on carrying value of the total equity of the property prior to the sale               $ 243,500,000