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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Operating Assets and Facilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 14,711.1		$ 14,330.6
Less: allowance for depreciation	(3,989.9)		(3,880.9)
Operating assets and facilities, net	10,721.2		10,449.7
Total depreciation expense	108.4	$ 100.5
Railcars and locomotives
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	13,033.1		12,702.9
Aircraft spare engines
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,030.4		1,030.4
Tank containers
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	253.9		241.4
Buildings, leasehold improvements, and other equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	274.5		265.3
Other
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 119.2		$ 90.6