Property and Equipment, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 85,124	$ 80,692
Less accumulated depreciation and amortization	(17,899)	(14,978)
Property and equipment, net	67,225	65,714
Right-of-use fixed assets	1,200	1,200
Finance Lease, Right-of-Use Asset, Accumulated Amortization	424	395
Interest costs capitalized	28	25	$ 26
Land for transportation purposes
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	6,538	6,431
Track structure
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	28,334	27,934
Other roadway a
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	32,478	31,478
Locomotives
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	10,528	8,496
Freight cars and other equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	3,838	3,808
Computer hardware, software and other
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	1,664	1,518
Construction in progress
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 1,744	$ 1,027
Minimum | Track structure
Property, Plant and Equipment [Line Items]
Useful life	15 years
Minimum | Other roadway a
Property, Plant and Equipment [Line Items]
Useful life	10 years
Minimum | Locomotives
Property, Plant and Equipment [Line Items]
Useful life	8 years
Minimum | Freight cars and other equipment
Property, Plant and Equipment [Line Items]
Useful life	8 years
Minimum | Computer hardware, software and other
Property, Plant and Equipment [Line Items]
Useful life	6 years
Maximum | Track structure
Property, Plant and Equipment [Line Items]
Useful life	55 years
Maximum | Other roadway a
Property, Plant and Equipment [Line Items]
Useful life	100 years
Maximum | Locomotives
Property, Plant and Equipment [Line Items]
Useful life	37 years
Maximum | Freight cars and other equipment
Property, Plant and Equipment [Line Items]
Useful life	43 years
Maximum | Computer hardware, software and other
Property, Plant and Equipment [Line Items]
Useful life	15 years