Note 1. Summary of Significant Accounting Policies Long-Lived Assets (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Impairment of long-lived assets	$ 369,400,000	$ 396,400,000	$ 0	$ 0
Other Assets [Member]
Restructuring Cost and Reserve [Line Items]
Assets Held-for-sale, Not Part of Disposal Group		32,900,000	$ 0
Railroad Transportation Equipment [Member]
Restructuring Cost and Reserve [Line Items]
Impairment of long-lived assets		369,400,000
Building [Member]
Restructuring Cost and Reserve [Line Items]
Impairment of long-lived assets		15,200,000
Investments [Domain]
Restructuring Cost and Reserve [Line Items]
Impairment of long-lived assets		$ 11,800,000