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Note 13 - Retirement Benefit Plans - Reconciliation of Level 3 Investments (Details) - Pension Plan [Member] - Foreign Plan [Member] - UK Pension Plan [Member] - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Fair value at beginning of year | $ 12.2 | $ 10.8
Purchases, sales, issuances and settlements, net | 0.1 | 0.2
Net gain | 0.6 | 0.8
Foreign currency | 0.4 | 0.4
Fair value at end of year | $ 13.3 | $ 12.2

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- Definition Amount of increase (decrease) in asset measured at fair value on recurring basis using unobservable input (level 3) due to foreign currency effects. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized from asset measured at fair value on recurring basis using unobservable input (level 3). + References No definition available. + Details
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- Definition Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Details
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- Details
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- Details
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