|
Equity (Details) (USD $)
In Millions, except Share data, unless otherwise specified |
3 Months Ended | |
|---|---|---|
|
Mar. 31, 2015
|
Mar. 31, 2014
|
|
| Class of Stock [Line Items] | ||
| Number of operating partnerships units converted into common shares (in units) | 158,000 | 48,498 |
| Common Shares | ||
| Class of Stock [Line Items] | ||
| Shares issued to the public (in units/ shares) | 890,241 | |
| Weighted average price per share of stock issued | 30.29 | |
| Net proceeds of stock issuance | 26.6 | |
| Commission costs | 0.4 | |
| Remaining capacity under ATM Plan | 84.0 | |
| Corporate Office Properties, L.P. | Common Shares | ||
| Class of Stock [Line Items] | ||
| Shares issued to the public (in units/ shares) | 890,241 | |