Note 1. Summary of Significant Accounting Policies Revenue Recognition (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Billed Contracts Receivable	$ 21.4	$ 2.9
Rail Products Group [Member] | Railcar products [Domain]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 3,200.9
Revenue, remaining performance obligation expected to be delivered in current year	53.40%
Rail Products Group [Member] | Railcar products [Domain] | External Customers [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 2,896.5
Rail Products Group [Member] | Railcar products [Domain] | Leasing [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	304.4
Rail Products Group [Member] | Sustainable Railcar Conversions
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 81.9
Revenue, remaining performance obligation expected to be delivered in current year	100.00%
Rail Products Group [Member] | Maintenance services [Domain]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 6.6
Revenue, remaining performance obligation expected to be delivered in current year	100.00%
Railcar Leasing and Management Services Group [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 65.0
Revenue, remaining performance obligation expected to be delivered in current year	27.00%