v2.4.0.6
Commitments And Contingencies (Details) (USD $)
 3 Months Ended
Mar. 31, 2013
Commitments And Contingencies [Line Items]  
Letter of credit and performance obligations $ 18,300,000
Property insurance program per occurrence limits 1,000,000,000
Per occurrence limit for NBCR Coverage 1,000,000,000
Value of program trigger 100,000,000
Coinsurance of program trigger 15.00%
Deductible in insurance as a percentage of the value of the affected property, San Francisco 5.00%
Per occurrence limit of the earthquake insurance which covers San Francisco region 120,000,000
Annual aggregate limit of the earthquake insurance which covers San Francisco region 120,000,000
Amount of earthquake insurance provided by IXP, LLC as direct insurer San Francisco 20,000,000
Earthquake Coverage Included in Builders Risk Policy for 680 Folsom 20,000,000
Earthquake Coverage Included In Builders Risk Policy For 535 Mission 15,000,000
Operating partnership guarantee to cover liabilities of IXP 20,000,000
767 Venture, LLC [Member]
  
Commitments And Contingencies [Line Items]  
Maximum funding obligation 14,400,000
Property insurance program per occurrence limits 1,625,000,000
Coverage for acts of Terrorism certified under TRIA in excess of amount provided by NYXP, LLC, as a direct insurer 1,375,000,000
Coverage for acts of terrorism certified under TRIA 250,000,000
John Hancock Tower [Member]
  
Commitments And Contingencies [Line Items]  
Guarantee Obligation Related To Tenant Re-Leasing Costs 2,400,000
601 Lexington Avenue [Member]
  
Commitments And Contingencies [Line Items]  
Coverage For Acts Of Terrorism Under TRIA Covered in Excess of Amount Covered by IXP $ 250,000,000