Quarterly report pursuant to Section 13 or 15(d)

Equity (Details)

v3.20.2
Equity (Details) - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Class of Stock [Line Items]          
Conversion of common units to common shares (in units/shares)     97,539 12,009 103,039
Dividends declared per share (in usd per share)   $ 0.275 $ 0.275 $ 0.825 $ 0.825
Common Shares          
Class of Stock [Line Items]          
Conversion of common units to common shares (in units/shares)       12,009  
Common Shares | 2018 Common Stock Issued to Public Under At-the-Market Program          
Class of Stock [Line Items]          
At the market, offering program established, aggregate value $ 300        
Corporate Office Properties, L.P.          
Class of Stock [Line Items]          
Dividends declared per share (in usd per share)   $ 0.275 $ 0.275 $ 0.825 $ 0.825