Note 4 - Fair Value Measurement (Details Textual) - USD ($) $ in Billions	Mar. 31, 2022	Dec. 31, 2021
Long-Term Debt, Total	$ 6.8	$ 6.8
Long-Term Debt, Fair Value	$ 6.7	$ 6.9

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant