Consolidated Statements of Shareholders' Deficit - USD ($) $ in Thousands	Total	Cumulative Effect Adjustment for Adoption of New Accounting Standard	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Distributions in Excess of Accumulated Earnings	Distributions in Excess of Accumulated Earnings Cumulative Effect Adjustment for Adoption of New Accounting Standard	Noncontrolling Interest - OP Units	Noncontrolling Interest - Non-voting Preferred Shares
Beginning balance, value at Dec. 31, 2017	$ (1,207,142)	$ 1,859	$ 17	$ 644,328	$ 7,821	$ (1,960,715)	$ 1,859	$ 101,407
Beginning balance, shares at Dec. 31, 2017			174,851,514
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201409Member
Net (loss) income	$ 16,545					16,187		358
At-the-market issuance of common stock, net of offering costs	109,442		$ 1	109,441
At-the-market issuance of common stock, net of offering, shares			5,496,763
Amortization of discount on convertible preferred stock	(2,980)			(2,980)
Other comprehensive income	22,811				22,284			527
Common stock dividends declared	(427,656)					(427,656)
Distributions to noncontrolling interest	(9,917)							(9,917)
Convertible preferred stock dividends	(2,624)					(2,624)
Net share settlement	(1,605)			(1,336)		(269)
Stock-based compensation	8,064			8,064
Stock-based compensation, shares			187,694
Ending balance, value at Dec. 31, 2018	$ (1,493,203)	$ (61,826)	$ 18	757,517	30,105	(2,373,218)	$ (61,826)	92,375
Ending balance, shares at Dec. 31, 2018			180,535,971
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201811Member
Net (loss) income	$ 10,908					10,582		326
At-the-market issuance of common stock, net of offering costs	21,641			21,641
At-the-market issuance of common stock, net of offering, shares			1,176,186
Amortization of discount on convertible preferred stock	(993)			(993)
Other comprehensive income	(54,675)				(53,547)			(1,128)
Common stock dividends declared	(69,403)					(69,403)
Distributions to noncontrolling interest	(1,329)							(1,329)
Exchange of noncontrolling interest				6,540				(6,540)
Exchange of noncontrolling interest, shares			666,576
Convertible preferred stock dividends	(875)					(875)
Equity settlement convertible preferred stock	87,500		$ 1	87,499
Equity settlement convertible preferred stock, shares			8,677,163
Net share settlement	(1,834)			(1,834)
Stock-based compensation	10,808			10,808
Stock-based compensation, shares			357,066
Equity settled contingent consideration	11,178			11,178
Equity settled contingent consideration, in shares			645,385
Issuance of common stock - employee stock purchase plan	884			884
Issuance of common stock - employee stock purchase plan, in shares			83,287
Equity component value of exchangeable note issuance, net	80,770			80,770
Deferred tax liability related to exchangeable note issuance	(3,499)			(3,499)
Sale of common stock warrant	50,819			50,819
Payment for bond hedge option	(70,035)			(70,035)
Ending balance, value at Dec. 31, 2019	$ (1,483,164)		$ 19	951,295	(23,442)	(2,494,740)		83,704
Ending balance, shares at Dec. 31, 2019			192,141,634
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Net (loss) income	$ (718,812)					(706,301)		(12,511)
Other comprehensive income	3,119				3,075			44
Common stock dividends declared	(129,414)					(129,414)
Distributions to noncontrolling interest	(2,080)							(2,080)
Cumulative non-voting convertible preferred stock	125								$ 125
Net share settlement	(1,097)			(1,097)
Stock-based compensation	13,721			13,721
Stock-based compensation, shares			390,066
Issuance of common stock - employee stock purchase plan	676			676
Issuance of common stock - employee stock purchase plan, in shares			96,788
Settlement Common Stock	244,550		$ 4	244,546
Settlement Common Stock, shares			38,633,470
Ending balance, value at Dec. 31, 2020	$ (2,072,376)		$ 23	$ 1,209,141	$ (20,367)	$ (3,330,455)		$ 69,157	$ 125
Ending balance, shares at Dec. 31, 2020			231,261,958