Note 10. Employee Retirement Plans Net Retirement Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Retirement Benefits [Abstract]
Service cost	$ 0.0	$ 0.0	$ 0.0
Interest	0.4	0.4	14.8
Expected return on plan assets	0.0	0.0	(20.9)
Amortization of actuarial loss	0.3	0.3	6.0
Amortization of prior service cost	0.0	0.0	1.2
Settlement loss	0.0	0.0	151.5
Net periodic benefit cost	0.7	0.7	152.6
Defined contribution expense	9.1	8.6	7.5
Pension Cost (Reversal of Cost)	$ 9.8	$ 9.3	$ 160.1