Annual report pursuant to Section 13 and 15(d)

Organization (Details 2)

v3.6.0.2
Organization (Details 2) - Corporate Office Properties, L.P. [Member]
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Common Units [Member]    
Forms of ownership in Operating Partnership and ownership percentage by the entity    
Percentage ownership in operating partnership 96.50% 96.30%
Preferred Units [Member]    
Forms of ownership in Operating Partnership and ownership percentage by the entity    
Percentage ownership in operating partnership 95.50%