Condensed Consolidated Statement of Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period Of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Distributions in Excess of Accumulated Earnings	Distributions in Excess of Accumulated Earnings Cumulative Effect, Period Of Adoption, Adjustment	Accumulated Other Comprehensive Loss	Noncontrolling Interest
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13	$ 6,403,504	$ (190)	$ 7	$ 7,121,927	$ (887,619)	$ (190)	$ (13,888)	$ 183,077
Balance at period beginning (in shares) at Dec. 31, 2019			66,092
Balance at period beginning at Dec. 31, 2019	6,403,504	$ (190)	$ 7	7,121,927	(887,619)	$ (190)	(13,888)	183,077
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	497,683				473,125			24,558
Cash flow hedge losses reclassified to earnings	3,282						3,171	111
Change in fair value of derivatives and amortization of swap settlements	(6,119)						(5,911)	(208)
Change in fair value of marketable debt securities, net	(178)						(172)	(6)
Issuance of common stock under:
Stock option and restricted stock plans, net (in shares)			95
Stock option and restricted stock plans, net	9,201			9,201
Sale of common stock, net	(228)			(228)
Equity based compensation costs	9,294			8,956				338
Retirement of common stock, net (in shares)			(985)
Retirement of common stock, net	(222,990)			(222,990)
Changes in the redemption value of redeemable noncontrolling interest	6,691			6,888				(197)
Changes in noncontrolling interest from acquisition	1,349							1,349
Distributions to noncontrolling interest	(23,689)							(23,689)
Redemptions of noncontrolling interest (in shares)			8
Redemptions of noncontrolling interest	(2,971)			(2,123)				(848)
Common stock dividends	(407,157)				(407,157)
Balance at period end (in shares) at Sep. 30, 2020			65,210
Balance at period end at Sep. 30, 2020	6,267,482		$ 7	6,921,631	(821,841)		(16,800)	184,485
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13	6,352,881		$ 7	6,944,805	(760,028)		(18,710)	186,807
Balance at period beginning (in shares) at Jun. 30, 2020			65,331
Balance at period beginning at Jun. 30, 2020	6,352,881		$ 7	6,944,805	(760,028)		(18,710)	186,807
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	78,842				73,661			5,181
Change in fair value of derivatives and amortization of swap settlements	1,884						1,821	63
Change in fair value of marketable debt securities, net	92						89	3
Issuance of common stock under:
Sale of common stock, net	(95)			(95)
Equity based compensation costs	2,361			2,279				82
Retirement of common stock, net (in shares)			(121)
Retirement of common stock, net	(26,586)			(26,586)
Changes in the redemption value of redeemable noncontrolling interest	2,522			2,346				176
Distributions to noncontrolling interest	(7,677)							(7,677)
Redemptions of noncontrolling interest	(1,268)			(1,118)				(150)
Common stock dividends	(135,474)				(135,474)
Balance at period end (in shares) at Sep. 30, 2020			65,210
Balance at period end at Sep. 30, 2020	6,267,482		$ 7	6,921,631	(821,841)		(16,800)	184,485
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13	6,267,482		7	6,921,631	(821,841)		(16,800)	184,485
Cumulative effect upon adoption of ASU No. 2016-13	6,183,192		$ 6	6,876,326	(861,193)		(14,729)	182,782
Balance at period beginning (in shares) at Dec. 31, 2020			64,999
Balance at period beginning at Dec. 31, 2020	6,183,192		$ 6	6,876,326	(861,193)		(14,729)	182,782
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	371,566				351,680			19,886
Change in fair value of derivatives and amortization of swap settlements	5,607						5,417	190
Change in fair value of marketable debt securities, net	356						344	12
Issuance of common stock under:
Stock option and restricted stock plans, net (in shares)			112
Stock option and restricted stock plans, net	12,402		$ 1	12,401
Sale of common stock, net	(202)			(202)
Equity based compensation costs	9,495			9,172				323
Retirement of common stock, net (in shares)			(40)
Retirement of common stock, net	(9,172)			(9,172)
Changes in the redemption value of redeemable noncontrolling interest	(4,922)			(5,499)				577
Contributions from noncontrolling interest	1,900							1,900
Distributions to noncontrolling interest	(22,114)							(22,114)
Redemptions of noncontrolling interest (in shares)			10
Redemptions of noncontrolling interest	(8,407)			(7,518)				(889)
Common stock dividends	(407,802)				(407,802)
Balance at period end (in shares) at Sep. 30, 2021			65,081
Balance at period end at Sep. 30, 2021	6,131,899		$ 7	6,875,508	(917,315)		(8,968)	182,667
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13	6,136,703		$ 7	6,862,879	(899,663)		(9,768)	183,248
Balance at period beginning (in shares) at Jun. 30, 2021			65,004
Balance at period beginning at Jun. 30, 2021	6,136,703		$ 7	6,862,879	(899,663)		(9,768)	183,248
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	125,002				118,390			6,612
Change in fair value of derivatives and amortization of swap settlements	728						704	24
Change in fair value of marketable debt securities, net	99						96	3
Issuance of common stock under:
Stock option and restricted stock plans, net (in shares)			68
Stock option and restricted stock plans, net	15,572			15,572
Sale of common stock, net	(118)			(118)
Equity based compensation costs	1,628			1,573				55
Changes in the redemption value of redeemable noncontrolling interest	1,673			1,253				420
Distributions to noncontrolling interest	(7,257)							(7,257)
Redemptions of noncontrolling interest (in shares)			9
Redemptions of noncontrolling interest	(6,089)			(5,651)				(438)
Common stock dividends	(136,042)				(136,042)
Balance at period end (in shares) at Sep. 30, 2021			65,081
Balance at period end at Sep. 30, 2021	6,131,899		$ 7	6,875,508	(917,315)		(8,968)	182,667
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13	$ 6,131,899		$ 7	$ 6,875,508	$ (917,315)		$ (8,968)	$ 182,667