Note 8 - Stockholders' Equity - Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Net income (loss)	$ 3	$ (281)	$ 9	$ 21	$ 24	$ 18	$ (269)	$ 63
Less: Dividends on Series A Preferred Stock	6			6			18	18
Net (loss) income attributable to common stockholders	$ (3)			$ 15			$ (287)	$ 45
Weighted average basic shares outstanding (in shares)	82.1			82.7			81.9	83.4
Effect of dilutive securities (in shares)	0.0			0.7			0.0	0.8
Weighted average diluted shares outstanding (in shares)	82.1			83.4			81.9	84.2
Basic (in dollars per share)	$ (0.04)			$ 0.18			$ (3.50)	$ 0.54
Diluted (in dollars per share)	$ (0.04)			$ 0.18			$ (3.50)	$ 0.53