Stockholders' Equity - Summary (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares at beginning of period	212,477,101	110,363,539	75,721,360
Shares issued for directors' fees	158,218	187,566	68,486
Shares issued for nonvested shares of common stock	1,847,700	2,332,114	801,579
Shares issued for debt exchange	0	0
Shares retired or forfeited	(813,422)	(406,118)	(296,415)
Shares at end of period	213,669,597	212,477,101	110,363,539
Shares at beginning of period	0	0	0
Treasury stock acquired	719,016	285,807	243,389
Treasury stock retired	(719,016)	(285,807)	(243,389)
Shares at end of period	0	0	0
Common stock, shares issued	213,669,597	212,477,101
7.0% Senior Notes
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued for debt exchange			10,863,000
Equity Offering
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares issued	0	0	23,205,529
Merger
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares issued	0	100,000,000	0