Annual report pursuant to Section 13 and 15(d)

Related Party Transactions (Details)

v2.4.0.6
Related Party Transactions (Details) (USD $)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Related Party Transaction [Line Items]      
Lease revenue $ 582,565,000 $ 586,710,000 $ 590,936,000
Mack [Member]
     
Related Party Transaction [Line Items]      
Lease revenue 238,000 253,000 250,000
Due from related parties 0 0  
RMC Entities [Member]
     
Related Party Transaction [Line Items]      
Area of property (in square feet) 4,860    
Lease expiration date Jun. 01, 2015    
Lease revenue 125,000 130,000 137,000
Due from related parties 0 92,000  
Related party revenue 869,000 1,200,000 1,400,000
Cali [Member]
     
Related Party Transaction [Line Items]      
Area of property (in square feet) 2,631    
Lease expiration date Dec. 31, 2014    
Lease revenue 65,000 69,000 68,000
Due from related parties 0 15,000  
Reimbursement revenue $ 162,000 $ 97,000 $ 101,000
Leased Office Space 1 [Member] | Mack [Member]
     
Related Party Transaction [Line Items]      
Area of property (in square feet) 717    
Lease expiration date Nov. 01, 2013    
Leased Office Space 2 [Member] | Mack [Member]
     
Related Party Transaction [Line Items]      
Area of property (in square feet) 6,317    
Lease expiration date Nov. 01, 2014    
Leased Property [Member] | Mack [Member]
     
Related Party Transaction [Line Items]      
Number of real estate properties 1    
Leased Property [Member] | RMC Entities [Member]
     
Related Party Transaction [Line Items]      
Number of real estate properties 1    
Leased Property [Member] | Cali [Member]
     
Related Party Transaction [Line Items]      
Number of real estate properties 1