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 9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Conversion of common units        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 3,591,000 3,679,000 3,648,000 0
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 0 434,000 434,000
Weighted average restricted stock and deferred shares        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 375,000 411,000 394,000 412,000
Weighted average options        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 233,000 440,000 307,000 480,000
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) 375,000 411,000 394,000 412,000
Corporate Office Properties, L.P. | Weighted average options        
Antidilutive securities        
Antidilutive securities excluded from computation of diluted earnings per share (in shares) 233,000 440,000 307,000 480,000
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 0 434,000 434,000