Note 7. Property, Plant, and Equipment Property, Plant, and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	$ 9,272.6	$ 9,105.6
Less accumulated depreciation, including partially-owned subsidiaries of $599.0 and $568.4	2,385.8	2,258.7
Property, Plant and Equipment, Net	6,886.8	6,846.9
Manufacturing Facility, Non-Operating [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Net	2.6
Intersegment Eliminations [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	(1,050.7)	(1,047.3)
NegativeAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	287.4	268.2
Property, Plant and Equipment, Net	(763.3)	(779.1)
Railcar Leasing and Management Services Group [Member] | Operating Segments [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Net	7,309.4	7,276.7
Manufacturing and Corporate [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	823.9	828.0
Less accumulated depreciation, including partially-owned subsidiaries of $599.0 and $568.4	483.2	478.7
Property, Plant and Equipment, Net	340.7	349.3
Manufacturing and Corporate [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	15.7	17.4
Manufacturing and Corporate [Member] | Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	384.6	377.4
Manufacturing and Corporate [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	405.5	415.1
Manufacturing and Corporate [Member] | Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	18.1	18.1
Wholly Owned Subsidiaries [Member] | Railcar Leasing and Management Services Group [Member] | Operating Segments [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	7,269.0	7,082.0
Less accumulated depreciation, including partially-owned subsidiaries of $599.0 and $568.4	1,480.9	1,375.9
Property, Plant and Equipment, Net	5,788.1	5,706.1
Wholly Owned Subsidiaries [Member] | Railcar Leasing and Management Services Group [Member] | Operating Segments [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	21.7	20.7
Wholly Owned Subsidiaries [Member] | Railcar Leasing and Management Services Group [Member] | Operating Segments [Member] | Railcars on Lease [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	7,247.3	7,061.3
Partially-Owned Subsidiaries [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	1,917.6	1,927.7
Less accumulated depreciation, including partially-owned subsidiaries of $599.0 and $568.4	599.0	568.4
Partially-Owned Subsidiaries [Member] | Railcar Leasing and Management Services Group [Member] | Operating Segments [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Net	1,521.3	1,570.6
Partially-Owned Subsidiaries [Member] | Railcar Leasing and Management Services Group [Member] | Operating Segments [Member] | Railcars on Lease [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, at cost, including partially-owned subsidiaries of $1,917.6 and $1,927.7	2,230.4	2,242.9
Less accumulated depreciation, including partially-owned subsidiaries of $599.0 and $568.4	$ 709.1	$ 672.3