Note 8 - Loss on Early Extinguishment of Debt (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Extinguishment Of Debt Disclosures [Abstract]
Fair value of Initial Conversion Shares	$ 506
Fair value of Mandatory Conversion Shares	13
Carrying value of 2019 Convertible Notes	(92)
Fair value of pro-rata share of embedded derivatives at Initial Conversion Date	(416)
Fair value of pro-rata share of embedded derivatives at Mandatory Conversion Date	(9)
Total	$ 2

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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