Note 9 - Redeemable, Convertible Preferred Stock - Schedule of Redeemable, Convertible Preferred Stock (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Redeemable, convertible preferred stock	$ 210	$ 203
Series B Preferred Stock [Member]
Redeemable, convertible preferred stock	96	95
Series C Preferred Stock [Member]
Redeemable, convertible preferred stock	$ 114	$ 108