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Note 14 - Debt - Schedule of Unsecured Debt (Details) (Parentheticals) - Unsecured Debt [Member] | 12 Months Ended
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Dec. 31, 2021
2.150% Notes, Due February 5, 2027 [Member] |
Debt Instrument, Interest Rate | 2.375%
Debt Instrument, Maturity Date | May 20, 2031
2.400% Notes, Due February 5, 2030 [Member] |
Debt Instrument, Interest Rate | 3.20%
Debt Instrument, Maturity Date | May 20, 2041
3.250% Notes, Due February 5, 2050 [Member] |
Debt Instrument, Interest Rate | 3.55%
Debt Instrument, Maturity Date | May 20, 2061
3.750% Notes, Due February 5, 2070 [Member] |
Debt Instrument, Interest Rate | 2.375%
Debt Instrument, Maturity Date | May 20, 2031
3.250% Notes, Due February 5, 2050, Issued April 7, 2020 [Member] |
Debt Instrument, Interest Rate | 2.95%
Debt Instrument, Maturity Date | Mar. 10, 2052

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