Annual report pursuant to Section 13 and 15(d)

Subsequent Events (Details Textual)

v2.4.0.6
Subsequent Events (Details Textual) (USD $)
1 Months Ended 12 Months Ended
Jan. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Subsequent Events (Additional Textual) [Abstract]        
Lease expiration date   Dec. 31, 2013    
Subsequent Events (Textual) [Abstract]        
Extended additional period of lease   11 years    
Annualized straight line rents   $ 1,400,000    
Leasing commission paid   1,738,000 6,000 7,000
Common shares issued 129,278      
Gross proceeds from common shares issued $ 2,400,000 $ 3,917,000 $ 37,294,000 $ 3,882,000
Baytown, Texas Office Building [Member]
       
Subsequent Events (Additional Textual) [Abstract]        
Lease expiration date Apr. 30, 2013