Quarterly report pursuant to Section 13 or 15(d)

Properties, Net (Details 4)

v3.5.0.2
Properties, Net (Details 4)
ft² in Thousands, $ in Thousands
3 Months Ended 9 Months Ended
Aug. 07, 2015
USD ($)
ft²
Apr. 15, 2015
USD ($)
ft²
Mar. 19, 2015
USD ($)
ft²
Sep. 30, 2016
USD ($)
Sep. 30, 2015
USD ($)
Sep. 30, 2016
USD ($)
Sep. 30, 2015
USD ($)
2015 Acquisitions              
Business Acquisition [Line Items]              
Contributed revenues       $ 9,200 $ 6,900 $ 27,600 $ 11,200
Contributed net income from continuing operations       $ 432 $ 487 $ 2,400 $ 697
250 W Pratt St | Baltimore, Maryland              
Business Acquisition [Line Items]              
Square footage of real estate properties (in square feet) | ft²     367        
Acquired property percentage leased     96.20%        
Total acquisition cost     $ 61,800        
2600 Park Tower Drive | Northern Virginia              
Business Acquisition [Line Items]              
Square footage of real estate properties (in square feet) | ft²   237          
Acquired property percentage leased   100.00%          
Total acquisition cost   $ 80,500          
100 and 30 Light Street | Baltimore, Maryland              
Business Acquisition [Line Items]              
Square footage of real estate properties (in square feet) | ft² 558            
Acquired property percentage leased 93.50%            
Total acquisition cost $ 121,200            
Business combination, liabilities assumed 55,000            
Fair value assumption of debt $ 55,500