Consolidated Statements of Equity (USD $)
In Thousands, except Share data, unless otherwise specified
Total
USD ($)
Preferred Shares
USD ($)
Common Shares
USD ($)
Additional Paid-in Capital
USD ($)
Cumulative Distributions in Excess of Net Income
USD ($)
Accumulated Other Comprehensive Income (Loss)
USD ($)
Noncontrolling Interests
USD ($)
Corporate Office Properties, L.P.
USD ($)
Corporate Office Properties, L.P.
Common Shares
USD ($)
Corporate Office Properties, L.P.
Accumulated Other Comprehensive Income (Loss)
USD ($)
Corporate Office Properties, L.P.
Noncontrolling Interests
USD ($)
Corporate Office Properties, L.P.
Limited Partner
Corporate Office Properties, L.P.
Limited Partner
Preferred Shares
USD ($)
Corporate Office Properties, L.P.
General Partner
Corporate Office Properties, L.P.
General Partner
Preferred Shares
USD ($)
Balance (COPT: 87,394,512 shares and 93,255,284 shares as of December 31, 2013 and 2014, respectively) at Dec. 31, 2013 $ 1,497,249 $ 249,083 $ 874 $ 1,814,015 $ (641,868) $ 3,480 $ 71,665 $ 1,497,249 $ 1,226,318 $ 3,605 $ 9,443   $ 8,800   $ 249,083
Balance (in units/ shares) at Dec. 31, 2013 87,394,512               91,372,212            
Balance (preferred units) at Dec. 31, 2013                         352,000   9,431,667
Increase (Decrease) in Shareholders' Equity                              
Conversion of common units to common shares (COPT: 48,498 shares and 158,000 shares for the three months ended March 31, 2014 and 2015, respectively) 0   0 651     (651)                
Exercise of share options (in units/shares) 26,614               26,614            
Exercise of share options (COPT: 26,614 shares and 70,374 shares for the three months ended March 31, 2014 and 2015, respectively) 568     568       568 568            
Share-based compensation issuance, net of redemptions (in units/shares) 125,307               125,307            
Share-based compensation issuance, net of redemptions (COPT: 125,307 and 162,370 shares issued, net of redemptions for the three months ended March 31, 2014 and 2015, respectively) 1,856   2 1,854       1,856 1,856            
Redemption of vested equity awards (in units/shares)                 0            
Redemption of vested equity awards (1,092)     (1,092)       (1,092) (1,092)            
Adjustments to noncontrolling interests resulting from changes in ownership of COPLP 0     (69)     69                
Comprehensive income 3,741       4,741 (1,408) 408 3,741 279 (1,472) 279   165   4,490
Dividends / Distributions to owners of common and preferred units (28,581)       (28,581)     (29,827) (25,172)       (165)   (4,490)
Distributions to owners of common and preferred units in COPLP (1,246)           (1,246)                
Adjustment to arrive at fair value of redeemable noncontrolling interest 540     540       540 540            
Balance (COPT: 87,594,931 shares and 94,536,269 shares as of March 31, 2014 and 2015, respectively) at Mar. 31, 2014 1,473,035 249,083 876 1,816,467 (665,708) 2,072 70,245 1,473,035 1,203,297 2,133 9,722   8,800   249,083
Balance (in units/ shares) at Mar. 31, 2014 87,594,931               91,524,133            
Balance (preferred units) at Mar. 31, 2014                         352,000   9,431,667
Balance (COPT: 87,394,512 shares and 93,255,284 shares as of December 31, 2013 and 2014, respectively) at Dec. 31, 2014 1,520,884 199,083 933 1,969,968 (717,264) (1,297) 69,461 1,520,884 1,305,219 (1,381) 9,163   8,800   199,083
Balance (in units/ shares) at Dec. 31, 2014 93,255,284               97,092,835     3,837,551   93,255,284  
Balance (preferred units) at Dec. 31, 2014                       352,000 352,000 7,431,667 7,431,667
Increase (Decrease) in Shareholders' Equity                              
Conversion of common units to common shares (COPT: 48,498 shares and 158,000 shares for the three months ended March 31, 2014 and 2015, respectively) 0   2 2,120     (2,122)                
Issuance of common units resulting from common shares issued under at-the-market program (in units)                 890,241            
Issuance of common units resulting from common shares issued under at-the-market program (COPT: 890,241 shares for the three months ended March 31, 2015) 26,535   9 26,526       26,535 26,535            
Exercise of share options (in units/shares) 70,374               70,374            
Exercise of share options (COPT: 26,614 shares and 70,374 shares for the three months ended March 31, 2014 and 2015, respectively) 1,845     1,845       1,845 1,845            
Share-based compensation issuance, net of redemptions (in units/shares) 162,370               162,370            
Share-based compensation issuance, net of redemptions (COPT: 125,307 and 162,370 shares issued, net of redemptions for the three months ended March 31, 2014 and 2015, respectively) 1,829   1 1,828       1,829 1,829            
Redemption of vested equity awards (in units/shares)                 0            
Redemption of vested equity awards (2,031)     (2,031)       (2,031) (2,031)            
Adjustments to noncontrolling interests resulting from changes in ownership of COPLP 0     (475)     475                
Comprehensive income 11,472       13,355 (2,650) 767 11,472 10,200 (2,756) 311   165   3,552
Dividends / Distributions to owners of common and preferred units (29,550)       (29,550)     (30,727) (27,010)       (165)   (3,552)
Distributions to owners of common and preferred units in COPLP (1,177)           (1,177)                
Distributions to noncontrolling interests in subsidiaries (4)           (4) (4)     (4)        
Adjustment to arrive at fair value of redeemable noncontrolling interest (73)     (73)       (73) (73)            
Balance (COPT: 87,594,931 shares and 94,536,269 shares as of March 31, 2014 and 2015, respectively) at Mar. 31, 2015 $ 1,529,730 $ 199,083 $ 945 $ 1,999,708 $ (733,459) $ (3,947) $ 67,400 $ 1,529,730 $ 1,316,514 $ (4,137) $ 9,470   $ 8,800   $ 199,083
Balance (in units/ shares) at Mar. 31, 2015 94,536,269               98,215,820     3,679,551   94,536,269  
Balance (preferred units) at Mar. 31, 2015                       352,000 352,000 7,431,667 7,431,667