Consolidated Statements of Equity - USD ($) $ in Thousands |
Total |
Forward Equity Sale Agreement [Member] |
Common Stock Issued to Public Under At-the-Market Program [Member] |
Common Shares [Member]
Common Stock Issued to Public Under At-the-Market Program [Member]
|
Preferred Shares [Member] |
Preferred Shares [Member]
Preferred Shares [Member]
|
Common Shares [Member] |
Common Shares [Member]
Forward Equity Sale Agreement [Member]
|
Common Shares [Member]
Common Stock Issued to Public Under At-the-Market Program [Member]
|
Additional Paid-in Capital [Member] |
Additional Paid-in Capital [Member]
Forward Equity Sale Agreement [Member]
|
Additional Paid-in Capital [Member]
Common Stock Issued to Public Under At-the-Market Program [Member]
|
Additional Paid-in Capital [Member]
Common Shares [Member]
Common Stock Issued to Public Under At-the-Market Program [Member]
|
Cumulative Distributions in Excess of Net Income [Member] |
Accumulated Other Comprehensive Income (Loss) [Member] |
Noncontrolling Interests [Member] |
Corporate Office Properties, L.P. [Member] |
Corporate Office Properties, L.P. [Member]
Forward Equity Sale Agreement [Member]
|
Corporate Office Properties, L.P. [Member]
Common Stock Issued to Public Under At-the-Market Program [Member]
|
Corporate Office Properties, L.P. [Member]
Common Shares [Member]
|
Corporate Office Properties, L.P. [Member]
Common Shares [Member]
Forward Equity Sale Agreement [Member]
|
Corporate Office Properties, L.P. [Member]
Common Shares [Member]
Common Stock Issued to Public Under At-the-Market Program [Member]
|
Corporate Office Properties, L.P. [Member]
Accumulated Other Comprehensive Income (Loss) [Member]
|
Corporate Office Properties, L.P. [Member]
Noncontrolling Interests [Member]
|
Corporate Office Properties, L.P. [Member]
Limited Partner [Member]
|
Corporate Office Properties, L.P. [Member]
Limited Partner [Member]
Preferred Shares [Member]
|
Corporate Office Properties, L.P. [Member]
General Partner [Member]
|
Corporate Office Properties, L.P. [Member]
General Partner [Member]
Preferred Shares [Member]
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Balance at Dec. 31, 2015 | $ 1,616,564 | $ 199,083 | $ 945 | $ 2,004,507 | $ (657,172) | $ (2,838) | $ 72,039 | $ 1,616,564 | $ 1,400,745 | $ (2,985) | $ 10,921 | $ 8,800 | $ 199,083 | |||||||||||||||
| Balance (in units/ shares) at Dec. 31, 2015 | 94,531,512 | 98,208,903 | ||||||||||||||||||||||||||
| Balance (preferred units) at Dec. 31, 2015 | 352,000 | 7,431,667 | ||||||||||||||||||||||||||
| Increase (Decrease) in Shareholders' Equity | ||||||||||||||||||||||||||||
| Redemption of preferred shares/units | (531,667) | (531,667) | ||||||||||||||||||||||||||
| Redemption of preferred shares/units (531,667 and 6,900,000 shares in 2016 and 2017, respectively) | $ (26,583) | (26,583) | 17 | (17) | (26,583) | $ (26,583) | ||||||||||||||||||||||
| Conversion of common units to common shares (87,000, 339,513 and 1,904,615 shares in 2016, 2017 and 2018, respectively) | 0 | 1 | 1,166 | (1,167) | ||||||||||||||||||||||||
| Common shares issued during the period (in units/shares) | 3,721,227 | 3,721,227 | ||||||||||||||||||||||||||
| Common shares issued during the period | $ 109,053 | $ 37 | $ 109,016 | $ 109,053 | $ 109,053 | |||||||||||||||||||||||
| Share-based compensation (158,912, 179,180 and 146,290 shares issued, net of redemptions in 2016, 2017 and 2018, respectively) | $ 7,453 | 2 | 7,451 | 7,453 | $ 7,453 | |||||||||||||||||||||||
| Share-based compensation (in shares/units) | 158,912 | 158,912 | ||||||||||||||||||||||||||
| Redemption of vested equity awards | $ (2,466) | (2,466) | (2,466) | $ (2,466) | ||||||||||||||||||||||||
| Adjustments to noncontrolling interests resulting from changes in ownership of COPLP | 0 | (2,158) | 2,158 | |||||||||||||||||||||||||
| Comprehensive income | 32,656 | 28,890 | 1,107 | 2,659 | 32,656 | 15,096 | 1,131 | 1,472 | $ 660 | 14,297 | ||||||||||||||||||
| Dividends/Distributions | (119,526) | (119,526) | (124,176) | (109,219) | $ (660) | $ (14,297) | ||||||||||||||||||||||
| Distributions to owners of common and preferred units in COPLP | (4,650) | (4,650) | ||||||||||||||||||||||||||
| Contributions from noncontrolling interests in other consolidated entities | 1,244 | 1,244 | 1,244 | 1,244 | ||||||||||||||||||||||||
| Distributions to noncontrolling interests in other consolidated entities | (16) | (16) | (16) | (16) | ||||||||||||||||||||||||
| Adjustment to arrive at fair value of redeemable noncontrolling interests | (621) | (621) | (621) | (621) | ||||||||||||||||||||||||
| Tax loss from share-based compensation | $ (331) | (331) | (331) | $ (331) | ||||||||||||||||||||||||
| Balance (preferred units) at Dec. 31, 2016 | 352,000 | 6,900,000 | ||||||||||||||||||||||||||
| Balance (in units/ shares) at Dec. 31, 2016 | 98,498,651 | 102,089,042 | ||||||||||||||||||||||||||
| Balance at Dec. 31, 2016 | $ 1,612,777 | 172,500 | 985 | 2,116,581 | (747,825) | (1,731) | 72,267 | 1,612,777 | $ 1,419,710 | (1,854) | 13,621 | $ 8,800 | $ 172,500 | |||||||||||||||
| Increase (Decrease) in Shareholders' Equity | ||||||||||||||||||||||||||||
| Redemption of preferred shares/units | (6,900,000) | (6,900,000) | ||||||||||||||||||||||||||
| Redemption of preferred shares/units (531,667 and 6,900,000 shares in 2016 and 2017, respectively) | (172,500) | (172,500) | 6,847 | (6,847) | (172,500) | $ (172,500) | ||||||||||||||||||||||
| Conversion of common units to common shares (87,000, 339,513 and 1,904,615 shares in 2016, 2017 and 2018, respectively) | $ 0 | 3 | 4,633 | (4,636) | ||||||||||||||||||||||||
| Common shares issued during the period (in units/shares) | 1,678,913 | 591,042 | 1,678,913 | 591,042 | ||||||||||||||||||||||||
| Common shares issued during the period | $ 49,944 | $ 19,668 | $ 17 | 6 | $ 49,927 | $ 19,662 | 49,944 | 19,668 | $ 49,944 | $ 19,668 | ||||||||||||||||||
| Exercise of share options (in units/shares) | 5,000 | 5,000 | ||||||||||||||||||||||||||
| Exercise of share options (5,000 shares in 2017) | $ 150 | 0 | 150 | 150 | $ 150 | |||||||||||||||||||||||
| Share-based compensation (158,912, 179,180 and 146,290 shares issued, net of redemptions in 2016, 2017 and 2018, respectively) | $ 6,095 | 2 | 6,093 | 6,095 | $ 6,095 | |||||||||||||||||||||||
| Share-based compensation (in shares/units) | 179,180 | 179,180 | ||||||||||||||||||||||||||
| Redemption of vested equity awards | $ (1,973) | (1,973) | (1,973) | $ (1,973) | ||||||||||||||||||||||||
| Adjustments to noncontrolling interests resulting from changes in ownership of COPLP | 0 | (1,486) | 1,486 | |||||||||||||||||||||||||
| Comprehensive income | 76,630 | 68,745 | 3,898 | 3,987 | 76,630 | 64,416 | 4,027 | 1,308 | 660 | 6,219 | ||||||||||||||||||
| Dividends/Distributions | (116,158) | (116,158) | (120,480) | (113,601) | $ (660) | $ (6,219) | ||||||||||||||||||||||
| Distributions to owners of common and preferred units in COPLP | (4,322) | (4,322) | ||||||||||||||||||||||||||
| Distributions to noncontrolling interests in other consolidated entities | (2,617) | (2,617) | (2,617) | (2,617) | ||||||||||||||||||||||||
| Adjustment to arrive at fair value of redeemable noncontrolling interests | 626 | 626 | 626 | 626 | ||||||||||||||||||||||||
| Tax loss from share-based compensation | $ (13) | (13) | (13) | $ (13) | ||||||||||||||||||||||||
| Balance (preferred units) at Dec. 31, 2017 | 352,000 | 352,000 | 0 | |||||||||||||||||||||||||
| Balance (in units/ shares) at Dec. 31, 2017 | 101,292,299 | 104,543,177 | 3,250,878 | 101,292,299 | ||||||||||||||||||||||||
| Balance at Dec. 31, 2017 | $ 1,468,307 | 0 | 1,013 | 2,201,047 | (802,085) | 2,167 | 66,165 | 1,468,307 | $ 1,445,022 | 2,173 | 12,312 | $ 8,800 | $ 0 | |||||||||||||||
| Increase (Decrease) in Shareholders' Equity | ||||||||||||||||||||||||||||
| Cumulative effect of accounting change for adoption of hedge accounting guidance | (276) | 276 | (276) | 276 | ||||||||||||||||||||||||
| Balance as adjusted | 1,468,307 | 0 | 1,013 | 2,201,047 | (802,361) | 2,443 | 66,165 | 1,468,307 | $ 1,444,746 | 2,449 | 12,312 | 8,800 | 0 | |||||||||||||||
| Conversion of common units to common shares (87,000, 339,513 and 1,904,615 shares in 2016, 2017 and 2018, respectively) | 0 | 19 | 27,394 | (27,413) | ||||||||||||||||||||||||
| Redemption of common units (in units) | (13,377) | |||||||||||||||||||||||||||
| Redemption of common units | (339) | (339) | (339) | $ (339) | ||||||||||||||||||||||||
| Common shares issued during the period (in units/shares) | 5,907,000 | 991,664 | 5,907,000 | 991,664 | ||||||||||||||||||||||||
| Common shares issued during the period | $ 172,294 | $ 29,732 | $ 59 | $ 10 | $ 172,235 | $ 29,722 | $ 172,294 | $ 29,732 | $ 172,294 | $ 29,732 | ||||||||||||||||||
| Share-based compensation (158,912, 179,180 and 146,290 shares issued, net of redemptions in 2016, 2017 and 2018, respectively) | $ 6,963 | 1 | 6,962 | 6,963 | $ 6,963 | |||||||||||||||||||||||
| Share-based compensation (in shares/units) | 146,290 | 146,290 | ||||||||||||||||||||||||||
| Redemption of vested equity awards | $ (1,702) | (1,702) | (1,702) | $ (1,702) | ||||||||||||||||||||||||
| Adjustments to noncontrolling interests resulting from changes in ownership of COPLP | 0 | (2,466) | 2,466 | |||||||||||||||||||||||||
| Comprehensive income | 73,550 | 72,301 | (2,681) | 3,930 | 73,550 | 74,043 | (2,570) | 1,417 | 660 | 0 | ||||||||||||||||||
| Dividends/Distributions | (116,748) | (116,748) | (119,905) | (119,245) | $ (660) | $ 0 | ||||||||||||||||||||||
| Distributions to owners of common and preferred units in COPLP | (3,157) | (3,157) | ||||||||||||||||||||||||||
| Distributions to noncontrolling interests in other consolidated entities | (15) | (15) | (15) | (15) | ||||||||||||||||||||||||
| Adjustment to arrive at fair value of redeemable noncontrolling interests | $ (1,837) | (1,837) | (1,837) | $ (1,837) | ||||||||||||||||||||||||
| Balance (preferred units) at Dec. 31, 2018 | 352,000 | 352,000 | 0 | |||||||||||||||||||||||||
| Balance (in units/ shares) at Dec. 31, 2018 | 110,241,868 | 111,574,754.000 | 1,332,886 | 110,241,868 | ||||||||||||||||||||||||
| Balance at Dec. 31, 2018 | $ 1,627,048 | $ 0 | $ 1,102 | $ 2,431,355 | $ (846,808) | $ (238) | $ 41,637 | $ 1,627,048 | $ 1,604,655 | $ (121) | $ 13,714 | $ 8,800 | $ 0 |