Quarterly report pursuant to Section 13 or 15(d)

Fair Value Disclosures (Financial Assets And Liabilities Not Measured At Fair Value) (Details)

v2.3.0.15
Fair Value Disclosures (Financial Assets And Liabilities Not Measured At Fair Value) (Details) (USD $)
In Thousands
Sep. 30, 2011
Dec. 31, 2010
Sep. 30, 2010
Dec. 31, 2009
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Cash and cash equivalents, carrying value $ 40,751 $ 78,767 $ 262,413 $ 11,203
Restricted cash, carrying value 23,267 20,486    
Mortgage notes payable 428,909 361,860    
Lines of credit payable, carrying value 193,000 100,000    
Notes payable, carrying value 657,378 753,587    
Cash and cash equivalents, fair value 40,751 78,767    
Restricted cash, fair value 23,267 20,486    
Mortgage notes payable, fair value 463,801 380,360    
Lines of credit payable, fair value 193,000 100,000    
Notes payable, fair value 726,957 785,637    
2445 M Street Note Receivable [Member]
       
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
2445 M Street note receivable, carrying value 6,844 7,090    
2445 M Street note receivable, fair value $ 7,807 $ 8,048