Note 11 - Debt - Schedule of Debt (Details) - Senior Notes, 4.876 Percent, Due 2025 [Member] - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Long-term debt	$ 304.6	$ 307.5
Long-term debt, fair value	$ 298.0	$ 295.4

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Section 50
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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-Name Accounting Standards Codification
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant