Consolidated Statements of Equity - USD ($) $ in Thousands |
Total |
Common Stock Issued to Public Under At-the-Market Program |
Forward Equity Sale Agreement |
Preferred Shares |
Common Shares |
Common Shares
Common Stock Issued to Public Under At-the-Market Program
|
Common Shares
Forward Equity Sale Agreement
|
Additional Paid-in Capital |
Additional Paid-in Capital
Common Stock Issued to Public Under At-the-Market Program
|
Additional Paid-in Capital
Forward Equity Sale Agreement
|
Cumulative Distributions in Excess of Net Income |
Accumulated Other Comprehensive Income (Loss) |
Noncontrolling Interests |
Corporate Office Properties, L.P. |
Corporate Office Properties, L.P.
Common Stock Issued to Public Under At-the-Market Program
|
Corporate Office Properties, L.P.
Forward Equity Sale Agreement
|
Corporate Office Properties, L.P.
Common Shares
|
Corporate Office Properties, L.P.
Common Shares
Common Stock Issued to Public Under At-the-Market Program
|
Corporate Office Properties, L.P.
Common Shares
Forward Equity Sale Agreement
|
Corporate Office Properties, L.P.
Accumulated Other Comprehensive Income (Loss)
|
Corporate Office Properties, L.P.
Noncontrolling Interests
|
Corporate Office Properties, L.P.
Limited Partner
|
Corporate Office Properties, L.P.
Limited Partner
Preferred Shares
|
Corporate Office Properties, L.P.
General Partner
|
Corporate Office Properties, L.P.
General Partner
Preferred Shares
|
Balance (COPT: 98,498,651 and 101,292,299 shares as of December 31, 2016 and 2017, respectively) 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
|
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
|
|
|
|
|
|
|
|
|
Increase (Decrease) in Shareholders' Equity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Redemption of preferred units resulting from redemption of preferred shares (in units) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
(6,900,000)
|
Redemption of preferred shares (6,900,000 shares) |
$ (172,500)
|
|
|
(172,500)
|
|
|
|
6,847
|
|
|
(6,847)
|
|
|
(172,500)
|
|
|
|
|
|
|
|
|
|
|
$ (172,500)
|
Conversion of common units to common shares (COPT: 187,000 and 53,817 shares for the six months ended June 30, 2017 and 2018, respectively) |
$ 0
|
|
|
|
2
|
|
|
2,562
|
|
|
|
|
(2,564)
|
|
|
|
|
|
|
|
|
|
|
|
|
Common shares issued during the period |
|
$ 19,668
|
|
|
|
$ 6
|
|
|
$ 19,662
|
|
|
|
|
|
$ 19,668
|
|
|
$ 19,668
|
|
|
|
|
|
|
|
Common shares issued during the period (in shares) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
591,042
|
|
|
|
|
|
|
|
Issuance of common units resulting from exercise of share options (in units) |
5,000
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
5,000
|
|
|
|
|
|
|
|
|
Issuance of common units resulting from exercise of share options (COPT: 5,000 shares for the six months ended June 30, 2017) |
$ 150
|
|
|
|
0
|
|
|
150
|
|
|
|
|
|
150
|
|
|
$ 150
|
|
|
|
|
|
|
|
|
Share-based compensation issuance, net of redemptions (in units/shares) |
189,948
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
189,948
|
|
|
|
|
|
|
|
|
Share-based compensation issuance, net of redemptions (COPT: 189,948 and 137,379 shares issued, net of redemptions for the six months ended June 30, 2017 and 2018, respectively) |
$ 3,047
|
|
|
|
2
|
|
|
3,045
|
|
|
|
|
|
3,047
|
|
|
$ 3,047
|
|
|
|
|
|
|
|
|
Redemption of vested equity awards |
(1,813)
|
|
|
|
|
|
|
(1,813)
|
|
|
|
|
|
(1,813)
|
|
|
(1,813)
|
|
|
|
|
|
|
|
|
Adjustments to noncontrolling interests resulting from changes in ownership of COPLP |
0
|
|
|
|
|
|
|
(514)
|
|
|
|
|
514
|
|
|
|
|
|
|
|
|
|
|
|
|
Comprehensive income |
41,047
|
|
|
|
|
|
|
|
|
|
38,545
|
568
|
1,934
|
41,047
|
|
|
33,209
|
|
|
588
|
701
|
|
$ 330
|
|
6,219
|
Dividends / Distributions to owners of common and preferred units |
(60,922)
|
|
|
|
|
|
|
|
|
|
(60,922)
|
|
|
(63,124)
|
|
|
(56,575)
|
|
|
|
|
|
$ (330)
|
|
$ (6,219)
|
Distributions to owners of common and preferred units in COPLP |
(2,202)
|
|
|
|
|
|
|
|
|
|
|
|
(2,202)
|
|
|
|
|
|
|
|
|
|
|
|
|
Distributions to noncontrolling interests in subsidiaries |
(2,610)
|
|
|
|
|
|
|
|
|
|
|
|
(2,610)
|
(2,610)
|
|
|
|
|
|
|
(2,610)
|
|
|
|
|
Adjustment to arrive at fair value of redeemable noncontrolling interests |
$ (401)
|
|
|
|
|
|
|
(401)
|
|
|
|
|
|
(401)
|
|
|
$ (401)
|
|
|
|
|
|
|
|
|
Balance (in units/shares) at Jun. 30, 2017 |
99,471,641
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
102,875,032
|
|
|
|
|
|
|
|
|
Balance (preferred units) at Jun. 30, 2017 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
352,000
|
|
0
|
Balance (COPT: 99,471,641 shares and 103,260,495 shares as of June 30, 2017 and 2018, respectively) at Jun. 30, 2017 |
$ 1,436,241
|
|
|
0
|
995
|
|
|
2,146,119
|
|
|
(777,049)
|
(1,163)
|
67,339
|
1,436,241
|
|
|
$ 1,416,995
|
|
|
(1,266)
|
11,712
|
|
$ 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
|
Balance (COPT: 98,498,651 and 101,292,299 shares as of December 31, 2016 and 2017, respectively) 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
|
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
|
|
Increase (Decrease) in Shareholders' Equity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Conversion of common units to common shares (COPT: 187,000 and 53,817 shares for the six months ended June 30, 2017 and 2018, respectively) |
$ 0
|
|
|
|
1
|
|
|
760
|
|
|
|
|
(761)
|
|
|
|
|
|
|
|
|
|
|
|
|
Common shares issued during the period |
|
|
$ 52,227
|
|
|
|
$ 18
|
|
|
$ 52,209
|
|
|
|
|
|
$ 52,227
|
|
|
$ 52,227
|
|
|
|
|
|
|
Common shares issued during the period (in shares) |
|
|
1,777,000
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1,777,000
|
|
|
|
|
|
|
Share-based compensation issuance, net of redemptions (in units/shares) |
137,379
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
137,379
|
|
|
|
|
|
|
|
|
Share-based compensation issuance, net of redemptions (COPT: 189,948 and 137,379 shares issued, net of redemptions for the six months ended June 30, 2017 and 2018, respectively) |
$ 3,400
|
|
|
|
1
|
|
|
3,399
|
|
|
|
|
|
3,400
|
|
|
$ 3,400
|
|
|
|
|
|
|
|
|
Redemption of vested equity awards |
(1,525)
|
|
|
|
|
|
|
(1,525)
|
|
|
|
|
|
(1,525)
|
|
|
(1,525)
|
|
|
|
|
|
|
|
|
Adjustments to noncontrolling interests resulting from changes in ownership of COPLP |
0
|
|
|
|
|
|
|
(702)
|
|
|
|
|
702
|
|
|
|
|
|
|
|
|
|
|
|
|
Comprehensive income |
45,422
|
|
|
|
|
|
|
|
|
|
36,584
|
6,569
|
2,269
|
45,422
|
|
|
37,736
|
|
|
6,786
|
570
|
|
$ 330
|
|
$ 0
|
Dividends / Distributions to owners of common and preferred units |
(56,493)
|
|
|
|
|
|
|
|
|
|
(56,493)
|
|
|
(58,581)
|
|
|
(58,251)
|
|
|
|
|
|
$ (330)
|
|
$ 0
|
Distributions to owners of common and preferred units in COPLP |
(2,088)
|
|
|
|
|
|
|
|
|
|
|
|
(2,088)
|
|
|
|
|
|
|
|
|
|
|
|
|
Distributions to noncontrolling interests in subsidiaries |
(7)
|
|
|
|
|
|
|
|
|
|
|
|
(7)
|
(7)
|
|
|
|
|
|
|
(7)
|
|
|
|
|
Adjustment to arrive at fair value of redeemable noncontrolling interests |
$ (758)
|
|
|
|
|
|
|
(758)
|
|
|
|
|
|
(758)
|
|
|
$ (758)
|
|
|
|
|
|
|
|
|
Balance (in units/shares) at Jun. 30, 2018 |
103,260,495
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
106,457,556
|
|
|
|
|
3,197,061
|
|
103,260,495
|
|
Balance (preferred units) at Jun. 30, 2018 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
352,000
|
352,000
|
|
0
|
Balance (COPT: 99,471,641 shares and 103,260,495 shares as of June 30, 2017 and 2018, respectively) at Jun. 30, 2018 |
$ 1,508,485
|
|
|
$ 0
|
$ 1,033
|
|
|
$ 2,254,430
|
|
|
$ (822,270)
|
$ 9,012
|
$ 66,280
|
$ 1,508,485
|
|
|
$ 1,477,575
|
|
|
$ 9,235
|
$ 12,875
|
|
$ 8,800
|
|
$ 0
|