Annual report pursuant to Section 13 and 15(d)

Nature Of Business (Details)

v2.4.0.8
Nature Of Business (Details) (USD $)
3 Months Ended 12 Months Ended 0 Months Ended 2 Months Ended 0 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Aug. 31, 2012
Research Boulevard 1700 [Member]
Dec. 20, 2012
Plumtree Medical Center [Member]
Apr. 05, 2011
Dulles Station, Phase I [Member]
Nov. 02, 2011
Industrial Portfolio [Member]
Dec. 31, 2013
Taxable Reit Subsidiary [Member]
Dec. 31, 2012
Taxable Reit Subsidiary [Member]
Mar. 19, 2013
Office Building [Member]
Atrium Building [Member]
Aug. 05, 2011
Office Building [Member]
Industrial Portfolio [Member]
properties
Nature of Business [Line Items]                          
Percentage of Distribution of Ordinary Taxable Income     90.00%                    
Gain on sale of properties     $ 22,144,000 $ 5,124,000 $ 97,491,000 $ 3,724,000 $ 1,400,000 $ 0 $ 97,491,000 [1]     $ 3,195,000  
Number of real estate properties                         2
Federal and state income tax liabilities recognized     0 0 1,138,000                
Real estate impairment 2,097,000 14,526,000 0 0 14,526,000                
Deferred Tax Assets     5,700,000                    
Deferred Tax Assets, Net                   0 0    
Deferred Tax Liabilities                   $ 600,000 $ 600,000    
Ordinary income     62.00% 72.00% 60.00%                
Return of capital     38.00% 26.00% 17.00%                
Qualified dividends     0.00% 0.00% 5.00%                
Unrecaptured Section 1250 gain     0.00% 2.00% 13.00%                
Capital gain     0.00% 0.00% 5.00%                
[1] The Industrial Portfolio consists of every property in our industrial segment and two office properties (the Crescent and Albemarle Point).