CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues:
Total revenues	$ 1,040,155	$ 1,117,164	$ 1,074,729
Expenses:
Property operating expenses	489,070	451,581	413,492
Depreciation and amortization	289,025	286,235	276,861
General and administrative	37,028	85,885	103,694
Acquisition and certain other transaction related costs	13,102	194	403
Impairment of assets	115,201	66,346	5,082
Total expenses	943,426	890,241	799,532
Gain on sale of properties	39,696	261,916	46,055
Dividend income	1,846	2,901	2,637
Gains and losses on equity securities, net	(41,898)	(20,724)	0
Interest and other income	941	667	406
Interest expense (including net amortization of debt premiums, discounts and issuance costs of $6,032, $6,221 and $5,282, respectively)	(180,112)	(179,287)	(165,019)
Loss on early extinguishment of debt	(44)	(22)	(7,627)
(Loss) income from continuing operations before income tax expense and equity in earnings of an investee	(82,842)	292,374	151,649
Income tax expense	(436)	(476)	(454)
Equity in earnings of an investee	400	516	608
Net income (loss)	(82,878)	292,414	151,803
Net income attributable to noncontrolling interest	(5,356)	(5,542)	(4,193)
Net (loss) income attributable to common shareholders	(88,234)	286,872	147,610
Other comprehensive income (loss):
Unrealized gain on investments in equity securities, net	0	0	47,138
Amounts reclassified from cumulative other comprehensive income to net income	175	0	5,082
Equity in unrealized gain (loss) of an investee	91	(68)	462
Other comprehensive income (loss)	266	(68)	52,682
Comprehensive (loss) income	(82,612)	292,346	204,485
Comprehensive income attributable to noncontrolling interest	(5,356)	(5,542)	(4,193)
Comprehensive (loss) income attributable to common shareholders	$ (87,968)	$ 286,804	$ 200,292
Weighted average shares used in computing earnings per common share:
Weighted average common shares outstanding (basic) (in shares)	237,604	237,511	237,420
Weighted average common shares outstanding (diluted) (in shares)	237,604	237,546	237,452
Per common share amounts (basic and diluted)
Net (loss) income attributable to common shareholders (in dollars per share)	$ (0.37)	$ 1.21	$ 0.62
Rental income
Revenues:
Total revenues	$ 606,558	$ 700,641	$ 681,022
Residents fees and services
Revenues:
Total revenues	$ 433,597	$ 416,523	$ 393,707