Consolidated Statement of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid- In-Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Noncontrolling Interests	Series I Preferred Stock Preferred Stock
Beginning Balance at Dec. 31, 2016	$ 7,750,911	$ 1,017	$ 5,624,545	$ (124,049)	$ 22,137	$ 1,578,893	$ 426,436	$ 221,932
Beginning Balance (in shares) at Dec. 31, 2016		100,562
Increase (Decrease) in Stockholders' Equity
Net income (loss)	85,673					101,374	(15,701)
Other comprehensive loss	(3,533)				(3,533)
Preferred dividends	(14,950)					(14,950)
DRSPP (in shares)		2
DRSPP proceeds	223		223
Conversion of units of the Operating Partnership to common stock (in shares)		202
Conversion of units in the Operating Partnership to common stock	21,574	$ 2	21,572
Reallocation of noncontrolling interest in the Operating Partnership	5,712					5,712
Equity component of repurchased exchangeable senior notes	(109,776)		(109,776)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)		87
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	29,787	$ 1	29,786
Repurchases of common stock (in shares)		(8,342)
Repurchases of common units	(848,048)	$ (83)	(621,324)			(226,641)
Proceeds from stock options exercised (in shares)		292
Proceeds from stock options exercised	23,314	$ 2	23,312
Contributions to consolidated joint venture interests	36,275						36,275
Deconsolidation of partially owned entity	(30,203)						(30,203)
Cash distributions to noncontrolling interests	(52,446)						(52,446)
Cash distributions declared ( per common share, none of which represented a return of capital for federal income tax purposes)	(305,059)					(305,059)
Deconsolidation of partially owned entity	(30,203)						(30,203)
Ending Balance at Dec. 31, 2017	6,589,454	$ 939	4,968,338	(124,049)	18,604	1,139,329	364,361	221,932
Ending Balance (in shares) at Dec. 31, 2017		92,803
Increase (Decrease) in Stockholders' Equity
Adjusted Balance	7,159,978	$ 939	4,968,338	(124,049)	18,604	1,709,853	364,361	221,932
Net income (loss)	247,256					247,262	(6)
Other comprehensive loss	(3,496)				(3,496)
Preferred dividends	(14,950)					(14,950)
DRSPP (in shares)		1
DRSPP proceeds	136		136
Conversion of units of the Operating Partnership to common stock (in shares)		160
Conversion of units in the Operating Partnership to common stock	16,303	$ 2	16,301
Reallocation of noncontrolling interest in the Operating Partnership	34,236					34,236
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)		149
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	17,484	$ 1	17,483
Repurchases of common stock (in shares)		(9,745)
Repurchases of common units	(937,795)	$ (98)	(522,482)			(415,215)
Proceeds from stock options exercised (in shares)		316
Proceeds from stock options exercised	28,912	$ 3	28,909
Contributions to consolidated joint venture interests	5,459						5,459
Deconsolidation of partially owned entity	(315,116)						(315,116)
Cash distributions to noncontrolling interests	(8,364)						(8,364)
Cash distributions declared ( per common share, none of which represented a return of capital for federal income tax purposes)	(282,188)					(282,188)
Deconsolidation of partially owned entity	(315,116)						(315,116)
Ending Balance at Dec. 31, 2018	5,947,855	$ 847	4,508,685	(124,049)	15,108	1,278,998	46,334	221,932
Ending Balance (in shares) at Dec. 31, 2018		83,684
Increase (Decrease) in Stockholders' Equity
Net income (loss)	267,275					270,434	(3,159)
Other comprehensive loss	(43,593)				(43,593)
Preferred dividends	(14,950)					(14,950)
DRSPP (in shares)		4
DRSPP proceeds	334		334
Conversion of units of the Operating Partnership to common stock (in shares)		5
Conversion of units in the Operating Partnership to common stock	471		471
Reallocation of noncontrolling interest in the Operating Partnership	(34,320)					(34,320)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)		105
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	25,763	$ 2	25,761
Repurchases of common stock (in shares)		(4,596)
Repurchases of common units	(384,399)	$ (46)	(248,287)			(136,066)
Contributions to consolidated joint venture interests	58,462						58,462
Cash distributions to noncontrolling interests	(478)						(478)
Cash distributions declared ( per common share, none of which represented a return of capital for federal income tax purposes)	(279,377)					(279,377)
Redemption of common units	(25,845)		(569)				(25,276)
Ending Balance at Dec. 31, 2019	$ 5,517,198	$ 803	$ 4,286,395	$ (124,049)	$ (28,485)	$ 1,084,719	$ 75,883	$ 221,932
Ending Balance (in shares) at Dec. 31, 2019		79,202