Note 8 - Employee Retirement Plans (Details Textual) $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($)
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 25

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration