Note 10. Employee Retirement Plans Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Retirement Benefits [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 1.1
Defined Benefit Plan, Plan Assets, Contributions by Employer	1.1	$ 31.6
Defined Contribution Plan, Expected Future Employer Discretionary Contributions, Next Fiscal Year	11.4
Defined Contribution Plan, Employer Discretionary Contribution Amount	10.6
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	225.0
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	$ 336.0