Note 8 - Earnings Per Share - Reconciliation of the Numerators and Denominators of the Earnings per Share Calculations (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net income (loss) available to common stockholders - Numerator basic and diluted	$ 45	$ 111	$ (71)	$ 141
Weighted-average common shares outstanding - Basic (in shares)	144.5	144.0	144.4	144.0
Employee compensation-related shares, including stock options (in shares)	0.7	0.8	0.0	0.8
Weighted-average common shares outstanding - Diluted (in shares)	145.2	144.8	144.4	144.8