Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation (Details)

v2.4.0.8
Stock Based Compensation (Details) (USD $)
In Millions, except Share data, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2014
Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation expense $ 1.3 $ 1.2 $ 3.8 $ 3.6
Restricted Share Awards [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Fair value of share grants vested     1.0 0.7
Total unvested restricted share awards (in shares) 207,082   207,082  
Weighted average grant date fair value (in dollars per share) $ 25.37   $ 25.37  
Total compensation costs, non-vested restricted share awards $ 1.7   $ 1.7  
Total compensation cost not yet recognized, period for recognition (in months)     17 months  
Washington Real Estate Investment Trust 2007 Omnibus Long-Term Incentive Plan [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock based plan, aggregate number of shares authorized (in shares) 2,000,000   2,000,000  
Stock based plan, period in effect (in years)     10 years