Condensed Consolidated Statements of Shareholders' Deficit (unaudited) - USD ($) $ in Thousands	Total	Cumulative Effect Adjustment for Adoption of New Accounting Standard	Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Cumulative Effect Adjustment for Adoption of New Accounting Standard	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, 2019	$ (1,483,164)		$ 19	$ 951,295		$ (23,442)	$ (2,494,740)		$ 83,704
Beginning balance, shares at Dec. 31, 2019			192,141,634
Net loss	(80,266)						(78,853)		(1,413)
Other comprehensive (loss) income	(5,370)					(5,275)			(95)
Common stock dividends declared	(29,184)						(29,184)
Distributions to noncontrolling interest	(520)								(520)
Cumulative non-voting convertible preferred stock	125									$ 125
Payments related to tax withholding for share-based compensation	(373)			(373)
Stock-based compensation	2,995			2,995
Stock-based compensation, shares			95,609
Issuance of common stock - employee stock purchase plan	306			306
Issuance of common stock - employee stock purchase plan, in shares			43,849
Ending balance, value at Mar. 31, 2020	(1,595,451)		$ 19	954,223		(28,717)	(2,602,777)		81,676	125
Ending balance, shares at Mar. 31, 2020			192,281,092
Beginning balance, value at Dec. 31, 2020	$ (2,072,376)	$ (45,310)	$ 23	1,209,141	$ (59,908)	(20,367)	(3,330,455)	$ 14,598	69,157	125
Beginning balance, shares at Dec. 31, 2020			231,261,958
Accounting Standards Update Extensible List	unit:AccountingStandardUpdate202006Member
Net loss	$ (4,502)						(4,438)		(64)
Other comprehensive (loss) income	2,829					2,787			42
Common stock dividends declared	(35,128)						(35,128)
Distributions to noncontrolling interest	(520)								(520)
Payments related to tax withholding for share-based compensation	(2,306)			(2,306)
Stock-based compensation	3,335			3,335
Stock-based compensation, shares			396,481
Issuance of common stock - employee stock purchase plan	288			288
Issuance of common stock - employee stock purchase plan, in shares			35,764
Ending balance, value at Mar. 31, 2021	$ (2,153,690)		$ 23	$ 1,150,550		$ (17,580)	$ (3,355,423)		$ 68,615	$ 125
Ending balance, shares at Mar. 31, 2021			231,694,203