Note 8 - Loss on Early Extinguishment of Debt (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Extinguishment Of Debt Disclosures [Abstract]
Fair value of Initial Conversion Shares		$ 506
Fair value of Mandatory Conversion Shares		13
Carrying value of Notes		(92)
Fair value of pro-rata share of embedded derivative at Initial Conversion		(416)
Fair value of pro-rata share of embedded derivative at Mandatory Conversion		(9)
Total	$ 2	$ 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
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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