Annual report pursuant to Section 13 and 15(d)

Disposition of Properties (Details)

v3.6.0.2
Disposition of Properties (Details) - Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
ft² in Thousands, $ in Thousands
 1 Months Ended 3 Months Ended 12 Months Ended
Sep. 30, 2016
USD ($)
Jan. 31, 2016
USD ($)
ft²
Oct. 31, 2015
USD ($)
ft²
Sep. 30, 2015
USD ($)
ft²
Dec. 31, 2014
USD ($)
ft²
Sep. 30, 2016
USD ($)
Mar. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Sep. 30, 2015
USD ($)
ft²
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                      
Gain on sale of assets and interests in unconsolidated entities                   $ 6,305 $ 106,721
Fort Myers [Member]                      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                      
Square Feet | ft²   199                  
Net Sales Price   $ 25,785                  
Gain on sale of assets and interests in unconsolidated entities   $ 4,887         $ 4,900        
Myrtle Beach Hwy 501 [Member]                      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                      
Net Sales Price $ 2,921                    
Gain on sale of assets and interests in unconsolidated entities $ 1,418         $ 1,400          
Barstow [Member]                      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                      
Square Feet | ft²     171                
Net Sales Price     $ 105,793                
Gain on sale of assets and interests in unconsolidated entities     $ 86,506         $ 86,500      
Kittery I & II, Tuscola, & West Branch [Member]                      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                      
Square Feet | ft²       439         439    
Net Sales Price       $ 43,304              
Gain on sale of assets and interests in unconsolidated entities       $ 20,215         $ 20,200    
Lincoln City [Member]                      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                      
Square Feet | ft²         270            
Net Sales Price         $ 38,993            
Gain on sale of assets and interests in unconsolidated entities         $ 7,513            
Kittery I & II, Tuscola, West Branch & Barstow [Member]                      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                      
Net Sales Price                     149,100
Restricted cash               $ 121,300     $ 121,300