Revenues - Schedule of Revenues Disaggregated by Lines of Business (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Revenue	$ 3,423	$ 3,681	[1]
Total Merchandise
Disaggregation of Revenue [Line Items]
Revenue	2,152	2,185
Chemicals
Disaggregation of Revenue [Line Items]
Revenue	698	693
Agricultural and Food Products
Disaggregation of Revenue [Line Items]
Revenue	408	407
Automotive
Disaggregation of Revenue [Line Items]
Revenue	271	293
Forest Products
Disaggregation of Revenue [Line Items]
Revenue	249	262
Metals and Equipment
Disaggregation of Revenue [Line Items]
Revenue	209	220
Minerals
Disaggregation of Revenue [Line Items]
Revenue	181	174
Fertilizers
Disaggregation of Revenue [Line Items]
Revenue	136	136
Intermodal
Disaggregation of Revenue [Line Items]
Revenue	493	506
Coal
Disaggregation of Revenue [Line Items]
Revenue	461	632
Trucking
Disaggregation of Revenue [Line Items]
Revenue	202	215
Other
Disaggregation of Revenue [Line Items]
Revenue	$ 115	$ 143

[1] See the 2024 annual report filed on Form 10-K for revision of prior period financial statements.