Consolidated Statements of Comprehensive Income (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Net income $ 14,735 $ 5,671
Other comprehensive loss    
Unrealized losses on interest rate derivatives (3,474) (2,123)
Other comprehensive loss (2,701) (1,428)
Comprehensive income 12,034 4,243
Comprehensive income attributable to noncontrolling interests (1,329) (911)
Comprehensive income attributable to COPT 10,705 3,332
Interest Expense [Member]    
Other comprehensive loss    
Losses on interest rate derivatives included in interest expense 773 695
Corporate Office Properties, L.P.    
Net income 14,735 5,671
Other comprehensive loss    
Unrealized losses on interest rate derivatives (3,474) (2,123)
Other comprehensive loss (2,701) (1,428)
Comprehensive income 12,034 4,243
Comprehensive income attributable to noncontrolling interests (873) (782)
Comprehensive income attributable to COPT 11,161 3,461
Corporate Office Properties, L.P. | Interest Expense [Member]    
Other comprehensive loss    
Losses on interest rate derivatives included in interest expense $ 773 $ 695