Quarterly report pursuant to Section 13 or 15(d)

Earnings Per Share ("EPS") and Earnings Per Unit ("EPU") (Details 2)

v3.5.0.2
Earnings Per Share ("EPS") and Earnings Per Unit ("EPU") (Details 2) - shares
 3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Conversion of common units        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 3,676,000 3,680,000 3,676,000 3,706,000
Conversion of Series I Preferred Units        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 176,000 176,000 176,000 176,000
Conversion of Series K Preferred Shares        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 434,000 434,000 434,000 434,000
Weighted average restricted stock and deferred shares        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 403,000 426,000 404,000 413,000
Weighted average options        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 309,000 473,000 344,000 472,000
Corporate Office Properties, L.P. | Weighted average restricted stock and deferred shares        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 403,000 426,000 404,000 413,000
Corporate Office Properties, L.P. | Weighted average options        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 309,000 473,000 344,000 472,000
Corporate Office Properties, L.P. | Conversion of Series I preferred units        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 176,000 176,000 176,000 176,000
Corporate Office Properties, L.P. | Conversion of Series K preferred units        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 434,000 434,000 434,000 434,000