CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Rental income	$ 691,699	$ 763,262	$ 774,600
Tenant reimbursements and other income	170,158	189,767	186,487
Total revenues	861,857	953,029	961,087
Expenses:
Operating expenses	387,982	410,045	397,673
Depreciation and amortization	227,532	234,402	230,284
General and administrative	113,155	80,504	49,312
Loss on asset impairment	185,067	124,253	0
Acquisition related costs	5	318	5,648
Total expenses	913,741	849,522	682,917
Operating (loss) income	(51,884)	103,507	278,170
Interest and other income	1,561	1,229	1,410
Interest expense (including net amortization of debt discounts, premiums and deferred financing fees of $(549), $9 and $3,296, respectively)	(143,230)	(173,011)	(202,055)
Gain (loss) on early extinguishment of debt	4,909	(60,052)	(287)
Gain on sale of equity investment	171,561	66,293	0
Gain on issuance of shares by an equity investee	17,020	0	7,246
(Loss) income from continuing operations before income tax expense and equity in earnings of investees	(63)	(62,034)	84,484
Income tax expense	(3,191)	(2,634)	(3,207)
Equity in earnings of investees	24,460	25,754	11,420
Income (loss) from continuing operations	21,206	(38,914)	92,697
Discontinued operations:
Income (loss) from discontinued operations	8,389	6,393	(4,341)
Loss on asset impairment from discontinued operations	(2,238)	(102,869)	(168,632)
Loss on early extinguishment of debt from discontinued operations	(3,345)	(1,011)	(1,608)
Net (loss) gain on sale of properties from discontinued operations	0	(22,162)	2,039
Income (loss) before gain on sale of properties	24,012	(158,563)	(79,845)
Gain on sale of properties	0	1,596	0
Net income (loss)	24,012	(156,967)	(79,845)
Net income attributable to noncontrolling interest in consolidated subsidiary	0	(20,093)	(15,576)
Net income (loss) attributable to Equity Commonwealth	24,012	(177,060)	(95,421)
Preferred distributions	(32,095)	(44,604)	(51,552)
Excess redemption price paid over carrying value of preferred shares	(16,205)	0	(4,985)
Net loss attributable to Equity Commonwealth common shareholders	(24,288)	(221,664)	(151,958)
Amounts attributable to Equity Commonwealth common shareholders:
(Loss) income from continuing operations	(27,094)	(102,015)	20,584
Income (loss) from discontinued operations	8,389	6,393	(4,341)
Loss on asset impairment from discontinued operations	(2,238)	(102,869)	(168,632)
Loss on early extinguishment of debt from discontinued operations	(3,345)	(1,011)	(1,608)
Net (loss) gain on sale of properties from discontinued operations	0	(22,162)	2,039
Net loss attributable to Equity Commonwealth common shareholders	$ (24,288)	$ (221,664)	$ (151,958)
Weighted average number of common shares outstanding - basic and diluted	125,163	112,378	83,750
Basic and diluted earnings per common share attributable to Equity Commonwealth common shareholders:
(Loss) income from continuing operations (in dollars per share)	$ (0.21)	$ (0.91)	$ 0.25
Income (loss) from discontinued operations (in dollars per share)	$ 0.02	$ (1.06)	$ (2.06)
Net loss (in dollars per share)	$ (0.19)	$ (1.97)	$ (1.81)