Note 20 - Other Postretirement Benefits - Weighted-average Assumed Healthcare Cost Trend Rates Used to Compute Other Post-retirement Amounts (Details)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Healthcare cost trend	6.24%	5.73%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	3.47%	3.32%
Year that the rate reaches the ultimate trend rate	2038	2040

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in YYYY format.

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