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Note 13 - Financial Instruments (Details Textual) - USD ($) $ in Millions | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current | $ 20 | $ 16
Debt Instrument, Fair Value Disclosure | 27,300 | 28,500
Fair Value of Total Debt Less of Carrying Value | 4,100 | 4,100
Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current | $ 20 | $ 16

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