Consolidated Statements of Equity - USD ($) $ in Thousands |
Total |
Common Shares [Member] |
Preferred Shares [Member] |
Common Shares [Member] |
Additional Paid-in Capital [Member] |
Additional Paid-in Capital [Member]
Common Shares [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]
Common Shares [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, 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
|
|
|
|
|
|
|
Balance (preferred units) at Dec. 31, 2014 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
352,000
|
|
7,431,667
|
Increase (Decrease) in Shareholders' Equity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Conversion of common units to common shares (160,160, 87,000 and 339,513 shares in 2015, 2016 and 2017, respectively) |
$ 0
|
|
|
2
|
2,149
|
|
|
|
(2,151)
|
|
|
|
|
|
|
|
|
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 (890,241, 3,721,227 and 591,042 shares in 2015, 2016 and 2017, respectively) |
|
$ 26,535
|
|
9
|
|
$ 26,526
|
|
|
|
26,535
|
$ 26,535
|
|
|
|
|
|
|
Exercise of share options (in units/shares) |
76,474
|
|
|
|
|
|
|
|
|
|
76,474
|
|
|
|
|
|
|
Exercise of share options (76,474 and 5,000 shares in 2015 and 2017 respectively) |
$ 2,008
|
|
|
|
2,008
|
|
|
|
|
2,008
|
$ 2,008
|
|
|
|
|
|
|
Share-based compensation (149,353, 158,912 and 179,180 shares issued, net of redemptions in 2015, 2016 and 2017, respectively) |
$ 7,398
|
|
|
1
|
7,397
|
|
|
|
|
7,398
|
$ 7,398
|
|
|
|
|
|
|
Share-based compensation (in shares/units) |
149,353
|
|
|
|
|
|
|
|
|
|
149,353
|
|
|
|
|
|
|
Redemption of vested equity awards |
$ (2,462)
|
|
|
|
(2,462)
|
|
|
|
|
(2,462)
|
$ (2,462)
|
|
|
|
|
|
|
Adjustments to noncontrolling interests resulting from changes in ownership of COPLP |
0
|
|
|
|
(682)
|
|
|
|
682
|
|
|
|
|
|
|
|
|
Comprehensive income |
185,247
|
|
|
|
|
|
178,300
|
(1,541)
|
8,488
|
185,247
|
170,488
|
(1,604)
|
1,493
|
|
$ 660
|
|
$ 14,210
|
Dividends/Distributions |
(118,208)
|
|
|
|
|
|
(118,208)
|
|
|
(122,914)
|
(108,044)
|
|
|
|
$ (660)
|
|
$ (14,210)
|
Distributions to owners of common and preferred units in COPLP |
(4,706)
|
|
|
|
|
|
|
|
(4,706)
|
|
|
|
|
|
|
|
|
Contributions from noncontrolling interests in other consolidated entities |
300
|
|
|
|
|
|
|
|
300
|
300
|
|
|
300
|
|
|
|
|
Distributions to noncontrolling interests in other consolidated entities |
(35)
|
|
|
|
|
|
|
|
(35)
|
(35)
|
|
|
(35)
|
|
|
|
|
Adjustment to arrive at fair value of redeemable noncontrolling interests |
116
|
|
|
|
116
|
|
|
|
|
116
|
116
|
|
|
|
|
|
|
Tax loss from share-based compensation |
$ (513)
|
|
|
|
(513)
|
|
|
|
|
(513)
|
$ (513)
|
|
|
|
|
|
|
Balance (preferred units) at Dec. 31, 2015 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
352,000
|
|
7,431,667
|
Balance (in units/ shares) at Dec. 31, 2015 |
94,531,512
|
|
|
|
|
|
|
|
|
|
98,208,903
|
|
|
|
|
|
|
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
|
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 (160,160, 87,000 and 339,513 shares in 2015, 2016 and 2017, respectively) |
0
|
|
|
1
|
1,166
|
|
|
|
(1,167)
|
|
|
|
|
|
|
|
|
Issuance of common units resulting from common shares issued under at-the-market program (in units) |
|
|
|
|
|
|
|
|
|
|
3,721,227
|
|
|
|
|
|
|
Issuance of common units resulting from common shares issued under at-the-market program (890,241, 3,721,227 and 591,042 shares in 2015, 2016 and 2017, respectively) |
109,053
|
|
|
37
|
109,016
|
|
|
|
|
109,053
|
$ 109,053
|
|
|
|
|
|
|
Share-based compensation (149,353, 158,912 and 179,180 shares issued, net of redemptions in 2015, 2016 and 2017, 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 |
14,543
|
|
|
|
|
|
11,439
|
1,107
|
1,997
|
14,543
|
(3,017)
|
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
|
|
|
|
0
|
|
|
|
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
|
352,000
|
6,900,000
|
6,900,000
|
Balance (in units/ shares) at Dec. 31, 2016 |
98,498,651
|
|
|
|
|
|
|
|
|
|
102,089,042
|
|
|
3,590,391
|
|
98,498,651
|
|
Balance at Dec. 31, 2016 |
$ 1,594,664
|
|
$ 172,500
|
985
|
2,116,581
|
|
(765,276)
|
(1,731)
|
71,605
|
1,594,664
|
$ 1,401,597
|
(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 (160,160, 87,000 and 339,513 shares in 2015, 2016 and 2017, respectively) |
0
|
|
|
3
|
4,633
|
|
|
|
(4,636)
|
|
|
|
|
|
|
|
|
Common shares issued under forward equity sale agreements (1,678,913 shares) |
49,944
|
|
|
17
|
49,927
|
|
|
|
|
49,944
|
$ (49,944)
|
|
|
|
|
|
|
Issuance of common units resulting from COPT forward equity sale agreements (in shares) |
|
|
|
|
|
|
|
|
|
|
1,678,913
|
|
|
|
|
|
|
Issuance of common units resulting from common shares issued under at-the-market program (in units) |
|
|
|
|
|
|
|
|
|
|
591,042
|
|
|
|
|
|
|
Issuance of common units resulting from common shares issued under at-the-market program (890,241, 3,721,227 and 591,042 shares in 2015, 2016 and 2017, respectively) |
$ 19,668
|
|
|
6
|
19,662
|
|
|
|
|
19,668
|
$ 19,668
|
|
|
|
|
|
|
Exercise of share options (in units/shares) |
5,000
|
|
|
|
|
|
|
|
|
|
5,000
|
|
|
|
|
|
|
Exercise of share options (76,474 and 5,000 shares in 2015 and 2017 respectively) |
$ 150
|
|
|
|
150
|
|
|
|
|
150
|
$ 150
|
|
|
|
|
|
|
Share-based compensation (149,353, 158,912 and 179,180 shares issued, net of redemptions in 2015, 2016 and 2017, 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 |
78,022
|
|
|
|
|
|
70,091
|
3,898
|
4,033
|
78,022
|
65,808
|
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
|
0
|
Balance (in units/ shares) at Dec. 31, 2017 |
101,292,299
|
|
|
|
|
|
|
|
|
|
104,543,177.000
|
|
|
3,250,878
|
|
101,292,299
|
|
Balance at Dec. 31, 2017 |
$ 1,451,586
|
|
$ 0
|
$ 1,013
|
$ 2,201,047
|
|
$ (818,190)
|
$ 2,167
|
$ 65,549
|
$ 1,451,586
|
$ 1,428,301
|
$ 2,173
|
$ 12,312
|
|
$ 8,800
|
|
$ 0
|