Segment Reporting and Significant Expenses- Schedule of Reconciliation of Segment Operating Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Segment Operating Income	$ 1,041	$ 1,337	[1]
Revenue	3,423	3,681	[1]
Trucking Expenses and Eliminations	(2,382)	(2,344)	[1]
Operating Income	1,041	1,337	[1]
Interest Expense	(209)	(210)	[1]
Other Income - Net	26	41	[1]
Earnings Before Income Taxes	858	1,168	[1]
Operating Segments
Segment Reporting Information [Line Items]
Segment Operating Income	1,038	1,331
Operating Income	1,038	1,331
Operating Segments | Rail Operations
Segment Reporting Information [Line Items]
Segment Operating Income	1,038	1,331
Revenue	3,221	3,466
Operating Income	1,038	1,331
Operating Segments | Trucking Operating Segment
Segment Reporting Information [Line Items]
Revenue	207	217
Trucking Expenses and Eliminations	(204)	(211)
Eliminations
Segment Reporting Information [Line Items]
Revenue	(5)	(2)
Trucking Expenses and Eliminations	5	2
Eliminations | Trucking Operating Segment
Segment Reporting Information [Line Items]
Revenue	202	215
Trucking Expenses and Eliminations	$ (199)	$ (209)

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