Note 3 - Revenues - Disaggregated Revenues (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenues	$ 806.3	$ 772.6	$ 1,588.9	$ 1,525.6
UNITED STATES
Revenues	651.3	627.5	1,289.7	1,249.0
UNITED KINGDOM
Revenues	66.3	63.1	131.7	123.1
Other Countries [Member]
Revenues	88.7	82.0	167.5	153.5
Insurance [Member] \| Underwriting [Member]
Revenues	569.1	549.6	1,121.2	1,081.6
Insurance [Member] \| Claims [Member]
Revenues	$ 237.2	$ 223.0	$ 467.7	$ 444.0

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details