CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Total Stockholders' Equity	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Distributions in Excess of Earnings [Member]	Noncontrolling Interests [Member]
Beginning balance at Dec. 31, 2016	$ 3,759,317	$ 3,542,995	$ 192,411	$ 932	$ 3,457,649	$ (107,997)	$ 216,322
Beginning balance (in shares) at Dec. 31, 2016				93,219,439
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	180,615	164,612				164,612	16,003
Redemption of Series G & H Preferred stock	(200,000)	(200,000)	(192,411)			(7,589)
Issuance of common stock	326,058	326,058		$ 46	326,012
Issuance of common stock (in shares)				4,662,577
Issuance of share-based compensation awards	5,890	5,890			5,890
Non-cash amortization of share-based compensation	26,319	26,319			26,319
Exercise of stock options	12,179	12,179		$ 4	12,175
Exercise of stock options (in shares)				285,000
Settlement of restricted stock units for shares of common stock	0			$ 3	(3)
Settlement of restricted stock units for shares of common stock (in shares)				317,848
Repurchase of common stock, stock options and restricted stock units	(12,986)			$ (2)	(12,984)
Repurchase of common stock, stock options and restricted stock units (in shares)				(168,881)
Exchange of common units of the Operating Partnership	0	10,939		$ 3	10,936		(10,939)
Exchange of common units of the Operating Partnership (in shares)				304,350
Contributions from noncontrolling interests in consolidated property partnerships	54,604	0			0		54,604
Distributions to noncontrolling interests in consolidated property partnerships	(16,542)						(16,542)
Adjustment for noncontrolling interest in the Operating Partnership	0	(3,502)			(3,502)		3,502
Preferred dividends and distributions	(5,774)	(5,774)				(5,774)
Dividends declared per share of common stock and common unit	(169,364)	(165,937)				(165,937)	(3,427)
Ending balance at Dec. 31, 2017	3,960,316	3,700,793	0	$ 986	3,822,492	(122,685)	259,523
Ending balance (in shares) at Dec. 31, 2017				98,620,333
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	277,926	258,415				258,415	19,511
Issuance of common stock	130,693	130,693		$ 18	130,675
Issuance of common stock (in shares)				1,817,195
Issuance of share-based compensation awards	3,926	3,926			3,926
Non-cash amortization of share-based compensation	35,890	35,890			35,890
Exercise of stock options	41	41			41
Exercise of stock options (in shares)				1,000
Settlement of restricted stock units for shares of common stock	0			$ 4	(4)
Settlement of restricted stock units for shares of common stock (in shares)				488,354
Repurchase of common stock, stock options and restricted stock units	(16,553)	(16,553)		$ (2)	(16,551)
Repurchase of common stock, stock options and restricted stock units (in shares)				(231,800)
Exchange of common units of the Operating Partnership	0	1,962		$ 1	1,961		(1,962)
Exchange of common units of the Operating Partnership (in shares)				51,906
Contributions from noncontrolling interests in consolidated property partnerships	8,273						8,273
Distributions to noncontrolling interests in consolidated property partnerships	(11,803)						(11,803)
Adjustment for noncontrolling interest in the Operating Partnership	0	(1,477)			(1,477)		1,477
Dividends declared per share of common stock and common unit	(187,448)	(183,783)				(183,783)	(3,665)
Ending balance at Dec. 31, 2018	$ 4,201,261	3,929,907	0	$ 1,007	3,976,953	(48,053)	271,354
Ending balance (in shares) at Dec. 31, 2018	100,746,988			100,746,988
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 215,229	195,443				195,443	19,786
Issuance of common stock	353,722	353,722		$ 50	353,672
Issuance of common stock (in shares)				5,000,000
Issuance of share-based compensation awards	4,664	4,664			4,664
Non-cash amortization of share-based compensation	32,813	32,813			32,813
Exercise of stock options	703	703			703
Exercise of stock options (in shares)				16,500
Settlement of restricted stock units for shares of common stock	0			$ 5	(5)
Settlement of restricted stock units for shares of common stock (in shares)				463,276
Repurchase of common stock, stock options and restricted stock units	(14,861)	(14,861)		$ (2)	(14,859)
Repurchase of common stock, stock options and restricted stock units (in shares)				(212,477)
Exchange of common units of the Operating Partnership	0	78			78		(78)
Distributions to noncontrolling interests in consolidated property partnerships	(12,952)						(12,952)
Adjustment for noncontrolling interest in the Operating Partnership	0	(3,102)			(3,102)		3,102
Dividends declared per share of common stock and common unit	(206,575)	(202,711)				(202,711)	(3,864)
Ending balance at Dec. 31, 2019	$ 4,570,858	$ 4,293,510	$ 0	$ 1,060	$ 4,350,917	$ (58,467)	$ 277,348
Ending balance (in shares) at Dec. 31, 2019	106,016,287			106,016,287