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Note 12 - Financial Instruments (Details Textual) - USD ($) $ in Millions | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current | $ 46 | $ 46
Debt Instrument, Fair Value Disclosure, Total | 32,000 | 32,900
Fair Value of Total Debt in Excess of Carrying Value | 200 | $ 3,200
Fair Value, Inputs, Level 2 [Member] | Bank Time Deposits and Government Agency Securities [Member] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current | $ 46 |

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