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v3.3.1.900

Equity - COPLP and Subsidiaries (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 16, 2014 | Jul. 16, 2013 | Jul. 15, 2013 | Nov. 30, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Preferred Stock |  |  |  |  |  |  |
Number of shares issued |  |  |  |  | 7,431,667 |  |
Aggregate liquidation preference |  |  |  |  | $ 199,083 | $ 199,083 |
Stock redeemed or called during period value |  |  |  |  |  | 50,000 | $ 84,750
Common Shares |  |  |  |  |  |  |
Shares issued to the public |  |  |  | 5,520,000 |  |  |
Per share value of common and preferred shares issued to the public (in dollars per share) |  |  |  | $ 27.30 |  |  |
Net proceeds from issue of shares after underwriter discounts but before offering expenses |  |  |  | $ 148,900 |  | $ 148,666 | $ 117,961
Number of common shares for each converted common unit (in shares) |  |  |  |  | 1 |  |
Number of operating partnerships units converted into common shares (in units) |  |  |  |  | 160,160 | 140,149 | 311,343
Dividends declared per common share |  |  |  |  | $ 1.1000 | $ 1.10 | $ 1.10
Preferred units in COPLP |  |  |  |  | $ 8,800 | $ 8,800 |
Common Stock Issued to Public Under At-the-Market Program [Member] |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |
Shares issued to the public |  |  | 1,500,000.0 |  | 890,241 |  | 1,500,000
Issuance of stock, weighted average price per share |  |  |  |  | $ 30.29 |  |
Payments of stock issuance costs |  |  | $ 600 |  | $ 400 |  |
Series H [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Annual dividend yield | 7.50% |  |  |  |  |  |
Preferred stock, redemption price per share | $ 25 |  |  |  |  |  |
Stock redeemed or called during period value | $ 50,000 |  |  |  |  |  |
Issuance costs associated with redeemed preferred shares | $ 1,800 |  |  |  |  |  |
Series K [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Number of shares issued |  |  |  |  | 531,667 |  |
Aggregate liquidation preference |  |  |  |  | $ 26,583 |  |
Annual dividend yield |  |  |  |  | 5.60% |  |
Annual dividend per share (in dollars per share) |  |  |  |  | $ 2.80000 |  |
Number of common shares to be issued on conversion of each preferred share |  |  |  |  | 0.8163 |  |
Series L [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Number of shares issued |  |  |  |  | 6,900,000 |  |
Aggregate liquidation preference |  |  |  |  | $ 172,500 |  |
Annual dividend yield |  |  |  |  | 7.375% |  |
Annual dividend per share (in dollars per share) |  |  |  |  | $ 1.84375 |  |
Corporate Office Properties, L.P. [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Number of shares issued |  |  |  |  | 7,431,667 |  |
Aggregate liquidation preference |  |  |  |  | $ 199,083 |  |
Stock redeemed or called during period value |  |  |  |  |  | 50,000 | $ 84,750
Common Shares |  |  |  |  |  |  |
Net proceeds from issue of shares after underwriter discounts but before offering expenses |  |  |  |  |  | $ 148,666 | $ 117,961
Number of common shares for each converted common unit (in shares) |  |  |  |  | 1 |  |
Number of operating partnerships units converted into common shares (in units) |  |  |  |  | 160,160.00 | 140,149.000 | 311,343.000
Dividends declared per common share |  |  |  |  | $ 1.1 | $ 1.10 | $ 1.10
Corporate Office Properties, L.P. [Member] | Common Stock Issued to Public Under At-the-Market Program [Member] |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |
Shares issued to the public |  | 1,500,000 |  |  | 890,241 |  |
Net proceeds from issue of shares after underwriter discounts but before offering expenses |  | $ 38,500 |  |  | $ 26,600 |  |
Issuance of stock, weighted average price per share |  | $ 26.05 |  |  | $ 30.29 |  |
Payments of stock issuance costs |  | $ 600 |  |  | $ 400 |  |
Corporate Office Properties, L.P. [Member] | Common Units [Member] |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |
Percentage ownership in operating partnership |  |  |  |  | 96.30% | 96.00% |
Corporate Office Properties, L.P. [Member] | Conversion of Series I preferred units [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Annual dividend yield |  |  |  |  | 7.50% |  |
Annual cumulative preferred return increment frequency |  |  |  |  | 5 years |  |
Common Shares |  |  |  |  |  |  |
Limited partners' capital account, units issued |  |  |  |  | 352,000 |  |
Preferred units in COPLP |  |  |  |  | $ 8,800 |  |
Preferred stock, liquidation preference per share |  |  |  |  | $ 25 |  |
Common units conversion basis units issuable |  |  |  |  | 0.5 |  |
Corporate Office Properties, L.P. [Member] | Series H [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Annual dividend yield | 7.50% |  |  |  |  |  |
Preferred stock, redemption price per share | $ 25 |  |  |  |  |  |
Stock redeemed or called during period value | $ 50,000 |  |  |  |  |  |
Issuance costs associated with redeemed preferred shares | $ 1,800 |  |  |  |  |  |
Corporate Office Properties, L.P. [Member] | Series K [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Number of shares issued |  |  |  |  | 531,667 |  |
Aggregate liquidation preference |  |  |  |  | $ 26,583 |  |
Annual dividend yield |  |  |  |  | 5.60% |  |
Annual dividend per share (in dollars per share) |  |  |  |  | $ 2.80000 |  |
Number of common shares to be issued on conversion of each preferred share |  |  |  |  | 0.8163 |  |
Corporate Office Properties, L.P. [Member] | Series L [Member] |  |  |  |  |  |  |
Preferred Stock |  |  |  |  |  |  |
Number of shares issued |  |  |  |  | 6,900,000 |  |
Aggregate liquidation preference |  |  |  |  | $ 172,500 |  |
Annual dividend yield |  |  |  |  | 7.375% |  |
Annual dividend per share (in dollars per share) |  |  |  |  | $ 1.84375 |  |
Corporate Office Properties, L.P. [Member] | Common Shares [Member] |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |
Shares issued to the public |  |  |  | 5,520,000 |  |  |
Per share value of common and preferred shares issued to the public (in dollars per share) |  |  |  | $ 27.30 |  |  |
Net proceeds from issue of shares after underwriter discounts but before offering expenses |  |  |  | $ 148,900 |  |  |

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