Earnings per Common Share - Antidilutive Securities (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average number of antidilutive potential common shares excluded from computation (in shares)	250	0	58,483
Series B Convertible Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average number of antidilutive potential common shares excluded from computation (in shares)	0	0	33,240
Common share warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average number of antidilutive potential common shares excluded from computation (in shares)	0	0	18,575
Employee stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average number of antidilutive potential common shares excluded from computation (in shares)	0	0	5,983
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average number of antidilutive potential common shares excluded from computation (in shares)	250	0	685
Equity forward contracts
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average number of antidilutive potential common shares excluded from computation (in shares)	0	0	0