CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Distributions in Excess of Accumulated Earnings	Total Common Shareholders' Equity	Noncontrolling Interests
Balance at Dec. 31, 2018	$ 2,081,947	$ 82	$ 1,548,603	$ 516	$ (89,696)	$ 1,459,505	$ 622,442
Balance (in Shares) at Dec. 31, 2018		81,557,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0		4,230			4,230	(4,230)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		250,000
Issuance of Common Shares	135,751	$ 5	135,746			135,751
Issuance of Common Shares		4,816,000
Dividends/distributions declared ($0, $0.28, $0.29 and $0.84 per Common Share/OP Unit for Three Months and Nine Months Ended September 30, 2020 and 2019)	(76,387)				(71,065)	(71,065)	(5,322)
Employee and trustee stock compensation, net	7,361		396			396	6,965
Employee and trustee stock compensation, net (in Shares)		21,000
Noncontrolling interest distributions	(34,595)						(34,595)
Noncontrolling interest contributions	161,628						161,628
Comprehensive (loss) income	(46,182)			(44,654)	31,735	(12,919)	(33,263)
Reallocation of noncontrolling interests	0		3,684			3,684	(3,684)
Balance at Sep. 30, 2019	2,229,523	$ 87	1,692,659	(44,138)	(129,026)	1,519,582	709,941
Balance (in Shares) at Sep. 30, 2019		86,644,000
Balance at Dec. 31, 2018	$ 2,081,947	$ 82	1,548,603	516	(89,696)	1,459,505	622,442
Balance (in Shares) at Dec. 31, 2018		81,557,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of Common Shares (in shares)	0
Balance at Dec. 31, 2019	$ 2,186,965	$ 87	1,706,357	(31,175)	(132,961)	1,542,308	644,657
Balance (in Shares) at Dec. 31, 2019	87,050,465	87,050,000
Balance at Jun. 30, 2019	$ 2,100,106	$ 84	1,625,906	(29,570)	(115,224)	1,481,196	618,910
Balance (in Shares) at Jun. 30, 2019		84,453,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0		720			720	(720)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		42,000
Issuance of Common Shares	60,637	$ 3	60,634			60,637
Issuance of Common Shares		2,149,000
Dividends/distributions declared ($0, $0.28, $0.29 and $0.84 per Common Share/OP Unit for Three Months and Nine Months Ended September 30, 2020 and 2019)	(26,025)				(24,260)	(24,260)	(1,765)
Employee and trustee stock compensation, net	1,916		148			148	1,768
Noncontrolling interest distributions	(29,713)						(29,713)
Noncontrolling interest contributions	129,438						129,438
Comprehensive (loss) income	(6,836)			(14,568)	10,458	(4,110)	(2,726)
Reallocation of noncontrolling interests	0		5,251			5,251	(5,251)
Balance at Sep. 30, 2019	2,229,523	$ 87	1,692,659	(44,138)	(129,026)	1,519,582	709,941
Balance (in Shares) at Sep. 30, 2019		86,644,000
Balance at Dec. 31, 2019	$ 2,186,965	$ 87	1,706,357	(31,175)	(132,961)	1,542,308	644,657
Balance (in Shares) at Dec. 31, 2019	87,050,465	87,050,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of change in accounting principle	$ (400)				(389)	(389)	(11)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0		6,544			6,544	(6,544)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		408,000
Acquisition of noncontrolling interest	588						588
Repurchase of Common Shares	(22,386)	$ (1)	(22,385)			(22,386)
Repurchase of Common Shares (in shares)		(1,219,000)
Dividends/distributions declared ($0, $0.28, $0.29 and $0.84 per Common Share/OP Unit for Three Months and Nine Months Ended September 30, 2020 and 2019)	(27,032)				(24,937)	(24,937)	(2,095)
Employee and trustee stock compensation, net	8,551		578			578	7,973
Employee and trustee stock compensation, net (in Shares)		27,000
Noncontrolling interest distributions	(24,654)						(24,654)
Noncontrolling interest contributions	36,736						36,736
Comprehensive (loss) income	(106,268)			(54,698)	1,966	(52,732)	(53,536)
Reallocation of noncontrolling interests	0		4,244			4,244	(4,244)
Balance at Sep. 30, 2020	$ 2,052,100	$ 86	1,695,338	(85,873)	(156,321)	1,453,230	598,870
Balance (in Shares) at Sep. 30, 2020	86,266,122	86,266,000
Balance at Jun. 30, 2020	$ 2,093,331	$ 86	1,693,006	(90,209)	(147,291)	1,455,592	637,739
Balance (in Shares) at Jun. 30, 2020		86,265,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends/distributions declared ($0, $0.28, $0.29 and $0.84 per Common Share/OP Unit for Three Months and Nine Months Ended September 30, 2020 and 2019)	(123)						(123)
Employee and trustee stock compensation, net	2,413		232			232	2,181
Employee and trustee stock compensation, net (in Shares)		1,000
Noncontrolling interest distributions	(20,117)						(20,117)
Noncontrolling interest contributions	8,427						8,427
Comprehensive (loss) income	(31,831)			4,336	(9,030)	(4,694)	(27,137)
Reallocation of noncontrolling interests	0		2,100			2,100	(2,100)
Balance at Sep. 30, 2020	$ 2,052,100	$ 86	$ 1,695,338	$ (85,873)	$ (156,321)	$ 1,453,230	$ 598,870
Balance (in Shares) at Sep. 30, 2020	86,266,122	86,266,000