Note 6 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Beginning balance	$ 80.9	$ 89.1	$ 78.5
Additions based on tax positions related to the current year	13.3	16.2	25.8
Additions/(reductions) based on tax positions taken in prior years	(2.9)
Additions/(reductions) based on tax positions taken in prior years		0.5	2.8
Reductions due to settlements	(1.4)	(14.6)	(8.0)
Reductions due to lapse of applicable statute of limitations	(11.9)	(10.3)	(10.0)
Ending balance	$ 78.0	$ 80.9	$ 89.1

Amount of unrecognized tax benefits.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 217
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-217

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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