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Note 13 - Debt - Schedule of Unsecured Debt (Details) - Unsecured Debt [Member] $ in Millions | Mar. 31, 2022 USD ($)
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2.8% Notes, Due February 14, 2032 [Member] |
Debt Instrument | $ 1,250
3.375% Notes, Due February 14, 2042 [Member] |
Debt Instrument | 500
The 3.5% Notes, Due February 14, 2053 [Member] |
Debt Instrument | 1,250
3.85% Notes, Due February 14, 2072 [Member] |
Debt Instrument | $ 500

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