Annual report pursuant to Section 13 and 15(d)

Subesquent Events (Details)

v2.4.0.8
Subesquent Events (Details) (USD $)
 12 Months Ended 0 Months Ended 6 Months Ended 0 Months Ended
Dec. 31, 2013
item
property
Dec. 31, 2012
property
Dec. 31, 2011
Jan. 06, 2014
Jan. 04, 2013
Feb. 28, 2014
Subsequent Event [Member]
item
Feb. 28, 2014
Subsequent Event [Member]
L&B Group [Member]
Mar. 03, 2013
Subsequent Event [Member]
Messr Lefkowitz [Member]
Mar. 03, 2013
Subsequent Event [Member]
Messr Thomas [Member]
Sep. 30, 2014
Scenario, Forecast [Member]
Subsequent Event [Member]
Messr Thomas [Member]
Feb. 18, 2014
5.11% Senior Unsecured Notes [Member]
Subsequent Event [Member]
Feb. 24, 2014
Keystone Portfolio [Member]
Scenario, Forecast [Member]
property
Subsequent Event [Line Items]                        
Severance benefits               $ 3,400,000 $ 3,100,000      
Stock options vested               11,457 33,605      
Restricted stock units vested 149,463 123,877 134,048         68,667 41,000      
Period for continuation of health insurance               48 months 48 months      
Consulting payment                   300,000    
Common stock, shares outstanding 88,247,591 87,536,292   87,928,002 87,537,250   477,300          
Percentage of noncontrolling interest 11.90% 12.20%         0.50%          
Agreement termination period prior to specified notice period             30 days          
Number of board members 10         11            
Repayments of senior unsecured notes $ 100,000,000 $ 221,019,000                 $ 200,000,000  
Interest rate of senior unsecured notes                     5.11%  
Number of properties sold 24 4                   15