Note 15 - Pension and Other Postretirement Benefit Plans - Schedule of Expected Benefit Payments (Details) $ in Thousands	Dec. 31, 2021 USD ($)
2022	$ 11,504
2023	11,395
2024	11,371
2025	11,443
2026	11,525
Year 2027-2031	58,808
Pension Plan [Member]
2022	43,826
2023	44,331
2024	42,723
2025	41,253
2026	42,622
Year 2027-2031	193,244
Other Postretirement Benefits Plan [Member]
2022	23,638
2023	22,893
2024	22,063
2025	21,810
2026	21,460
Year 2027-2031	$ 101,663

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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