Revenues - Revenues Disaggregated by Lines of Business (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Line Items]
Revenue	$ 3,706	$ 3,413
Total Merchandise
Disaggregation of Revenue [Line Items]
Revenue	2,163	1,921
Chemicals
Disaggregation of Revenue [Line Items]
Revenue	650	618
Agricultural and Food Products
Disaggregation of Revenue [Line Items]
Revenue	437	387
Automotive
Disaggregation of Revenue [Line Items]
Revenue	274	227
Forest Products
Disaggregation of Revenue [Line Items]
Revenue	261	228
Metals and Equipment
Disaggregation of Revenue [Line Items]
Revenue	239	197
Minerals
Disaggregation of Revenue [Line Items]
Revenue	173	144
Fertilizers
Disaggregation of Revenue [Line Items]
Revenue	129	120
Coal
Disaggregation of Revenue [Line Items]
Revenue	633	533
Intermodal
Disaggregation of Revenue [Line Items]
Revenue	499	527
Trucking
Disaggregation of Revenue [Line Items]
Revenue	233	230
Other
Disaggregation of Revenue [Line Items]
Revenue	$ 178	$ 202