Note 9. Income Taxes Deferred Tax Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Deferred Tax Liabilities, Property, Plant and Equipment	$ 913.4	$ 718.4
Deferred Tax Liabilities, Partially Owned Subsidiaries	144.7	131.7
Deferred Tax Liabilities, Right-of-use Assets	10.0	0.0
Deferred Tax Liabilities, Gross	1,068.1	850.1
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits	3.1	5.7
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Warranty Reserves	4.5	8.1
Deferred Tax Assets, Other	46.1	34.0
Deferred Tax Assets, Tax Credit Carryforwards	229.0	65.5
Deferred Tax Assets, Inventory	5.1	8.9
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities	9.7	9.1
Deferred Tax Assets, Lease Liabilities	10.0	0.0
Deferred Tax Assets, Gross	307.5	131.3
Deferred Tax Liabilities, Net, Before Adjustments	760.6	718.8
Deferred Tax Assets, Valuation Allowance	19.5	15.1
Deferred Tax Liabilities, Net, Before Uncertain Tax Positions	780.1	733.9
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other	(1.0)	(2.3)
Deferred Tax Liabilities, Net	779.1	$ 731.6
Deferred Tax Assets, Operating Loss Carryforwards, Domestic	940.5
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	13.2
Deferred Tax Assets, Tax Credit Carryforwards, Other	$ 18.9