BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Useful Life (Details)	Dec. 31, 2023
Minimum | Railcars and locomotives
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	40 years
Minimum | Track and track related assets
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	15 years
Minimum | Bridges and tunnels
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	15 years
Minimum | Buildings and site improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	20 years
Minimum | Railroad equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	3 years
Minimum | Terminal machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	15 years
Minimum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	3 years
Minimum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	3 years
Minimum | Vehicles
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	5 years
Maximum | Railcars and locomotives
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	50 years
Maximum | Track and track related assets
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	50 years
Maximum | Bridges and tunnels
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	55 years
Maximum | Buildings and site improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	30 years
Maximum | Railroad equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	15 years
Maximum | Terminal machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	25 years
Maximum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	6 years
Maximum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	5 years
Maximum | Vehicles
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, useful life	7 years