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		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Net income (loss) available to common stockholders - Numerator basic and diluted	$ 53	$ (174)	$ 124	$ (116)
Weighted-average common shares outstanding - Basic (in shares)	145.2	144.5	145.1	144.4
Employee compensation-related shares, including stock options (in shares)	1.5	0.0	1.4	0.0
Weighted-average common shares outstanding - Diluted (in shares)	146.7	144.5	146.5	144.4