Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Capital in Excess of Par Value	Accumulated Deficit	AOCL
Beginning balance, value at Dec. 31, 2018	$ 2,801,749	$ 166,177	$ 4,289	$ 4,995,697	$ (2,357,255)	$ (7,159)
Preferred shares outstanding, beginning balance at Dec. 31, 2018		6,900,000
Common shares outstanding, beginning balance at Dec. 31, 2018			85,787,355
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	43,578				43,578
Dividends declared on preferred stock	(2,588)				(2,588)
Net (loss) income attributable to common stockholders/after preferred distributions	40,990				40,990
Other comprehensive income (loss)	(5,021)					(5,021)
Dividends declared on common stock	(54,254)				(54,254)
Tax withholdings related to net stock settlements	(704)		$ (1)		(703)
Tax withholdings related to net stock settlements (in shares)			(17,800)
Issuance of stock	32,686		$ 45	32,641
Issuance of stock (in shares)			893,526
Other	(79)			(79)
Stock-based compensation, net	3,269		$ 8	3,570	(309)
Stock-based compensation, net (in shares)			148,705
Ending balance, value at Mar. 31, 2019	2,818,636	$ 166,177	$ 4,341	5,031,829	(2,371,531)	(12,180)
Preferred shares outstanding, ending balance at Mar. 31, 2019		6,900,000
Common shares outstanding, ending balance at Mar. 31, 2019			86,811,786
Beginning balance, value at Dec. 31, 2019	$ 3,413,249	$ 166,177	$ 5,124	5,686,247	(2,432,838)	(11,461)
Preferred shares outstanding, beginning balance at Dec. 31, 2019	6,900,000	6,900,000
Common shares outstanding, beginning balance at Dec. 31, 2019	102,476,152		102,476,152
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ (15,847)				(15,847)
Dividends declared on preferred stock	(2,588)				(2,588)
Net (loss) income attributable to common stockholders/after preferred distributions	(18,435)				(18,435)
Other comprehensive income (loss)	702					702
Dividends declared on common stock	(64,338)				(64,338)
Tax withholdings related to net stock settlements	$ (2,349)		$ (2)		(2,347)
Tax withholdings related to net stock settlements (in shares)	(44,500)		(44,488)
Issuance of stock	$ 17,598		$ 18	17,580
Issuance of stock (in shares)			362,481
Stock-based compensation, net	2,981		$ 7	3,444	(470)
Stock-based compensation, net (in shares)			148,017
Ending balance, value at Mar. 31, 2020	$ 3,349,408	$ 166,177	$ 5,147	$ 5,707,271	$ (2,518,428)	$ (10,759)
Preferred shares outstanding, ending balance at Mar. 31, 2020	6,900,000	6,900,000
Common shares outstanding, ending balance at Mar. 31, 2020	102,942,162		102,942,162