Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital [Member]	Distributions in Excess of Accumulated Earnings [Member]	Accumulated Other Comprehensive Loss, Net	Noncontrolling Interest
Balances at Dec. 31, 2016	$ 6,292,237	$ 6	$ 7,029,679	$ (805,409)	$ (32,098)	$ 100,059
Balances (in shares) at Dec. 31, 2016		65,528
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	458,043			433,059		24,984
Reversal of unrealized gains upon the sale of marketable securities	(1,909)				(1,846)	(63)
Change in fair value of derivatives and amortization of swap settlements before guidance	12,744				12,322	422
Cash flow hedge losses reclassified to earnings	0
Change in fair value of marketable securities, net	3,284				3,176	108
Issuance of common stock under:
Stock option and restricted stock plans, net	26,635		26,635
Stock option and restricted stock plans, net (in shares)		179
Sale of common stock, net	89,055	$ 1	89,054
Sale of common stock, net (in shares)		345
Equity based compensation costs	11,302		9,529			1,773
Changes in the redemption value of redeemable noncontrolling interest	(65)		(136)			71
Changes in noncontrolling interest from acquisition	22,506					22,506
Distributions to noncontrolling interest	(27,051)					(27,051)
Redemptions of noncontrolling interest	(28,580)		(25,190)			(3,390)
Redemptions of noncontrolling interest (in shares)		2
Common stock dividends	(461,376)			(461,376)
Balances at Dec. 31, 2017	6,396,825	$ 7	7,129,571	(833,726)	(18,446)	119,419
Balances (in shares) at Dec. 31, 2017		66,054
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	413,599			390,153		23,446
Reversal of unrealized gains upon the sale of marketable securities	13				13	0
Change in fair value of derivatives and amortization of swap settlements before guidance	7,824				7,564	260
Cash flow hedge losses reclassified to earnings	0
Change in fair value of marketable securities, net	(118)				(114)	(4)
Issuance of common stock under:
Stock option and restricted stock plans, net	6,213		6,213
Stock option and restricted stock plans, net (in shares)		41
Sale of common stock, net	(919)	$ 0	(919)
Sale of common stock, net (in shares)		0
Equity based compensation costs	12,851		11,651			1,200
Retirement of common stock, net	(51,233)		(51,233)
Retirement of common stock, net (in shares)		(210)
Changes in the redemption value of redeemable noncontrolling interest	(1,164)		(1,143)			(21)
Changes in noncontrolling interest from acquisition	7,919					7,919
Distributions to noncontrolling interest	(29,233)					(29,233)
Redemptions of noncontrolling interest	(1,333)		(1,061)			(272)
Redemptions of noncontrolling interest (in shares)		5
Common stock dividends	(491,108)			(491,108)
Balances at Dec. 31, 2018	6,393,844	$ 7	7,093,079	(812,796)	(13,217)	126,771
Balances (in shares) at Dec. 31, 2018		65,890
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	464,448			439,286		25,162
Reversal of unrealized gains upon the sale of marketable securities	(32)				(31)	(1)
Cash flow hedge losses reclassified to earnings	1,824				1,762	62
Change in fair value of derivatives and amortization of swap settlements	(2,948)				(2,849)	(99)
Change in fair value of marketable securities, net	281				272	9
Issuance of common stock under:
Stock option and restricted stock plans, net	33,779		33,779
Stock option and restricted stock plans, net (in shares)		195
Sale of common stock, net	72,539		72,539
Sale of common stock, net (in shares)		228
Equity based compensation costs	12,283		11,029			1,254
Retirement of common stock, net	(56,989)		(56,989)
Retirement of common stock, net (in shares)		(234)
Changes in the redemption value of redeemable noncontrolling interest	(2,008)		(3,427)			1,419
Changes in noncontrolling interest from acquisition	65,472					65,472
Distributions to noncontrolling interest	(28,493)					(28,493)
Redemptions of noncontrolling interest	(36,568)		(28,083)			(8,485)
Redemptions of noncontrolling interest (in shares)		13
Common stock dividends	(514,109)			(514,109)
Balances at Dec. 31, 2019	$ 6,403,504	$ 7	$ 7,121,927	$ (887,619)	$ (13,888)	$ 183,077
Balances (in shares) at Dec. 31, 2019		66,092