Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Operating Assets and Facilities (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 19,695.8		$ 19,695.8		$ 15,662.6
Less: allowance for depreciation	(4,426.1)		(4,426.1)		(4,251.7)
Operating assets and facilities, net	15,269.7		15,269.7		11,410.9
Total depreciation expense	172.1	$ 111.9	346.7	$ 220.3
Railcars and locomotives
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	17,784.0		17,784.0		13,802.1
Aircraft spare engines
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,177.7		1,177.7		1,177.5
Tank containers
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	277.3		277.3		278.0
Buildings, leasehold improvements, and other equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	324.0		324.0		318.5
Other
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 132.8		$ 132.8		$ 86.5