CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Total Stockholders' Equity	Total Stockholders' Equity Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2017					140,993,985
Balance at Dec. 31, 2017	$ 3,967,999	$ (424,859)	$ 3,681,578	$ (424,859)	$ 1,410	$ 4,510,489	$ (830,279)	$ (424,859)	$ (42)	$ 286,421
Increase (Decrease) in Stockholders' Equity
Net (loss) income	$ 68,972		60,020				60,020			8,952
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Interest rate cap/swap agreements	$ (4,424)		(4,424)						(4,424)
Amortization of share and unit-based plans (in shares)					125,723
Amortization of share and unit-based plans	33,551		33,551		$ 1	33,550
Employee stock purchases (in shares)					35,293
Employee stock purchases	1,570		1,570			1,570
Distributions declared	(419,239)		(419,239)				(419,239)
Distributions to noncontrolling interests	(34,395)									(34,395)
Contributions from noncontrolling interests	16									16
Conversion of noncontrolling interests to common shares (in shares)					66,711
Conversion of noncontrolling interests to common shares	0		75		$ 1	74				(75)
Redemption of noncontrolling interests	(759)		(511)			(511)				(248)
Adjustment of noncontrolling interests in Operating Partnership	0		22,471			22,471				(22,471)
Balance (in shares) at Dec. 31, 2018					141,221,712
Balance at Dec. 31, 2018	3,188,432	$ (2,203)	2,950,232	$ (2,203)	$ 1,412	4,567,643	(1,614,357)	$ (2,203)	(4,466)	238,200
Increase (Decrease) in Stockholders' Equity
Net (loss) income	102,554		96,820				96,820			5,734
Interest rate cap/swap agreements	(4,585)		(4,585)						(4,585)
Amortization of share and unit-based plans (in shares)					106,747
Amortization of share and unit-based plans	16,723		16,723		$ 1	16,722
Employee stock purchases (in shares)					58,191
Employee stock purchases	1,519		1,519		$ 1	1,518
Distributions declared	(424,272)		(424,272)				(424,272)
Distributions to noncontrolling interests	(50,262)									(50,262)
Contributions from noncontrolling interests	3,131									3,131
Conversion of noncontrolling interests to common shares (in shares)					21,000
Conversion of noncontrolling interests to common shares	0		1,005			1,005				(1,005)
Redemption of noncontrolling interests	(67)		(31)			(31)				(36)
Adjustment of noncontrolling interests in Operating Partnership	$ 0		(2,946)			(2,946)				2,946
Balance (in shares) at Dec. 31, 2019	141,407,650				141,407,650
Balance at Dec. 31, 2019	$ 2,830,970		2,632,262		$ 1,414	4,583,911	(1,944,012)		(9,051)	198,708
Increase (Decrease) in Stockholders' Equity
Net (loss) income	(245,462)		(230,203)				(230,203)			(15,259)
Interest rate cap/swap agreements	843		843						843
Amortization of share and unit-based plans (in shares)					151,468
Amortization of share and unit-based plans	18,066		18,066		$ 1	18,065
Employee stock purchases (in shares)					265,386
Employee stock purchases	1,531		1,531		$ 3	1,528
Distributions declared	(165,404)		(165,404)				(165,404)
Stock dividend (in shares)					7,759,280
Stock dividend	0				$ 78	(78)
Distributions to noncontrolling interests	(14,458)									(14,458)
Contributions from noncontrolling interests	19,203									19,203
Conversion of noncontrolling interests to common shares (in shares)					186,791
Conversion of noncontrolling interests to common shares	0		12,086		$ 2	12,084				(12,086)
Redemption of noncontrolling interests	(29)		25			25				(54)
Adjustment of noncontrolling interests in Operating Partnership	$ 0		(12,157)			(12,157)				12,157
Balance (in shares) at Dec. 31, 2020	149,770,575				149,770,575
Balance at Dec. 31, 2020	$ 2,445,260		$ 2,257,049		$ 1,498	$ 4,603,378	$ (2,339,619)		$ (8,208)	$ 188,211