Note 10. Income Taxes Components of Income Tax Expense / Benefit (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Current Federal Tax Expense (Benefit)									$ 60.1	$ 38.7	$ 1.6
Current State and Local Tax Expense (Benefit)									2.6	1.3	3.5
Current Foreign Tax Expense (Benefit)									9.8	10.5	7.8
Current Income Tax Expense (Benefit)									72.5	50.5	12.9
Deferred Federal Income Tax Expense (Benefit)									(24.1)	(20.7)	14.5
Deferred State and Local Income Tax Expense (Benefit)									1.5	(8.1)	0.4
Deferred Foreign Income Tax Expense (Benefit)									0.5	(12.7)	(0.2)
Provision (benefit) for deferred income taxes									(22.1)	(41.5)	14.7
Provision (benefit) for income taxes:	$ 6.7	$ 15.6	$ 17.1	$ 11.0	$ 7.1	$ 6.0	$ 7.4	$ (11.5)	$ 50.4	$ 9.0	$ 27.6