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Note 12 - Financial Instruments (Details Textual) - USD ($) $ in Millions | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current | $ 16 | $ 46
Debt Instrument, Fair Value Disclosure | 25,900 | 28,100
Fair Value of Total Debt Less of Carrying Value | 7,000 | 5,200
Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current | $ 16 | $ 46

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