Note 7 - Goodwill and Intangible Assets - Intangible Assets and Related Accumulated Amortization (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Cost	$ 997.2	$ 951.9
Accumulated amortization	(609.3)	(559.5)
Net	$ 387.9	$ 392.4
Technology-Based Intangible Assets [Member]
Weighted average useful life (Year)	8 years	8 years
Cost	$ 379.3	$ 364.9
Accumulated amortization	(305.3)	(285.3)
Net	$ 74.0	$ 79.6
Marketing-Related Intangible Assets [Member]
Weighted average useful life (Year)	6 years	6 years
Cost	$ 39.7	$ 37.8
Accumulated amortization	(37.8)	(35.5)
Net	$ 1.9	$ 2.3
Contract-Based Intangible Assets [Member]
Weighted average useful life (Year)	6 years	6 years
Cost	$ 5.0	$ 5.0
Accumulated amortization	(5.0)	(5.0)
Net	$ 0.0	$ 0.0
Customer-Related Intangible Assets [Member]
Weighted average useful life (Year)	13 years	13 years
Cost	$ 557.7	$ 529.1
Accumulated amortization	(250.3)	(224.0)
Net	$ 307.4	$ 305.1
Database [Member]
Weighted average useful life (Year)	8 years	8 years
Cost	$ 15.5	$ 15.1
Accumulated amortization	(10.9)	(9.7)
Net	$ 4.6	$ 5.4

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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