Consolidated Statement Of Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Shares	Common Shares	Additional Paid-in Capital	Accumulated Dividends in Excess of Net Income	Accumulated Other Comprehensive (Loss) Income	Noncontrolling Interests	Common Shares Additional Paid-in Capital
Beginning balance (in shares) at Dec. 31, 2018		405,896	74,249,633
Beginning balance at Dec. 31, 2018	$ 2,467,330	$ 159,997	$ 745	$ 3,004,442	$ (818,877)	$ (416)	$ 121,439
Increase (Decrease) in Stockholders' Equity [Roll Forward]
January 1st adoption of new accounting standard	(7,098)				(7,098)
Net income, excluding amounts attributable to redeemable noncontrolling interests	142,687				141,046		1,641
Other comprehensive loss - change in fair value of interest rate swaps	(608)					(608)
Dividends declared to common shareholders	(152,555)				(152,555)
Dividends declared to preferred shareholders	(4,021)				(4,021)
Distributions declared to noncontrolling interests	(7,664)						(7,664)
Shares issued (in shares)			511,954
Shares issued	68,304		$ 5					$ 68,299
Shares issued under dividend reinvestment plan (in shares)			8,121
Shares issued under dividend reinvestment plan	1,054			1,054
Share-based compensation expense, net of forfeitures (in shares)			102,137
Share-based compensation expense, net of forfeitures	6,992		$ 1	6,991
Shares withheld for employee taxes (in shares)			(32,900)
Shares withheld for employee taxes	(4,442)			(4,442)
Conversion and redemption of OP units (in Shares)			111,252
Conversion and redemption of OP units	0		$ 1	11,935			(11,936)
Adjustment to redeemable noncontrolling interests	667			667
Ending balance (in shares) at Jun. 30, 2019		405,896	74,950,197
Ending balance at Jun. 30, 2019	2,510,646	$ 159,997	$ 752	3,088,946	(841,505)	(1,024)	103,480
Beginning balance (in shares) at Mar. 31, 2019		405,896	74,836,984
Beginning balance at Mar. 31, 2019	2,501,563	$ 159,997	$ 752	3,071,981	(843,947)	(625)	113,405
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income, excluding amounts attributable to redeemable noncontrolling interests	81,760				80,902		858
Other comprehensive loss - change in fair value of interest rate swaps	(399)					(399)
Dividends declared to common shareholders	(76,449)				(76,449)
Dividends declared to preferred shareholders	(2,011)				(2,011)
Distributions declared to noncontrolling interests	(6,398)						(6,398)
Shares issued (in shares)			65,822
Shares issued	8,951		$ 0					8,951
Shares issued under dividend reinvestment plan (in shares)			3,848
Shares issued under dividend reinvestment plan	526			526
Share-based compensation expense, net of forfeitures (in shares)			1,551
Share-based compensation expense, net of forfeitures	3,131		$ 0	3,131
Shares withheld for employee taxes (in shares)			(214)
Shares withheld for employee taxes	(28)			(28)
Conversion and redemption of OP units (in Shares)			42,206
Conversion and redemption of OP units	0		$ 0	4,385			(4,385)
Ending balance (in shares) at Jun. 30, 2019		405,896	74,950,197
Ending balance at Jun. 30, 2019	2,510,646	$ 159,997	$ 752	3,088,946	(841,505)	(1,024)	103,480
Beginning balance (in shares) at Dec. 31, 2019		405,896	75,540,804
Beginning balance at Dec. 31, 2019	2,636,132	$ 159,997	$ 759	3,166,522	(791,124)	(813)	100,791
Increase (Decrease) in Stockholders' Equity [Roll Forward]
January 1st adoption of new accounting standard	(510)				(510)
Net income, excluding amounts attributable to redeemable noncontrolling interests	66,143				65,270		873
Other comprehensive loss - change in fair value of interest rate swaps	(6,945)					(6,945)
Dividends declared to common shareholders	(158,810)				(158,810)
Dividends declared to preferred shareholders	(4,021)				(4,021)
Distributions declared to noncontrolling interests	(1,677)						(1,677)
Shares issued (in shares)			29
Shares issued	2		$ 0					2
Shares issued under dividend reinvestment plan (in shares)			10,605
Shares issued under dividend reinvestment plan	955			955
Share-based compensation expense, net of forfeitures (in shares)			114,092
Share-based compensation expense, net of forfeitures	7,029		$ 1	7,028
Shares withheld for employee taxes (in shares)			(32,390)
Shares withheld for employee taxes	(3,997)			(3,997)
Conversion and redemption of OP units (in Shares)			0
Conversion and redemption of OP units	(3,320)		$ 0	(30)			(3,290)
Contributions from noncontrolling interests	120						120
Ending balance (in shares) at Jun. 30, 2020		405,896	75,633,140
Ending balance at Jun. 30, 2020	2,531,101	$ 159,997	$ 760	3,170,480	(889,195)	(7,758)	96,817
Beginning balance (in shares) at Mar. 31, 2020		405,896	75,622,504
Beginning balance at Mar. 31, 2020	2,599,608	$ 159,997	$ 760	3,166,899	(818,284)	(7,265)	97,501
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income, excluding amounts attributable to redeemable noncontrolling interests	10,717				10,507		210
Other comprehensive loss - change in fair value of interest rate swaps	(493)					(493)
Dividends declared to common shareholders	(79,407)				(79,407)
Dividends declared to preferred shareholders	(2,011)				(2,011)
Distributions declared to noncontrolling interests	(894)						(894)
Shares issued (in shares)			16
Shares issued	0		$ 0					$ 0
Shares issued under dividend reinvestment plan (in shares)			6,771
Shares issued under dividend reinvestment plan	509			509
Share-based compensation expense, net of forfeitures (in shares)			4,026
Share-based compensation expense, net of forfeitures	3,087		$ 0	3,087
Shares withheld for employee taxes (in shares)			(177)
Shares withheld for employee taxes	(15)			(15)
Conversion and redemption of OP units (in Shares)			0
Conversion and redemption of OP units	0		$ 0	0			0
Contributions from noncontrolling interests	0						0
Ending balance (in shares) at Jun. 30, 2020		405,896	75,633,140
Ending balance at Jun. 30, 2020	$ 2,531,101	$ 159,997	$ 760	$ 3,170,480	$ (889,195)	$ (7,758)	$ 96,817