SEGMENT INFORMATION - Schedule of Sales by Product (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Total sales	$ 2,950	$ 2,610
Freight Segment
Segment Reporting Information [Line Items]
Total sales	2,115	1,901
Transit Segment
Segment Reporting Information [Line Items]
Total sales	835	709
Services
Segment Reporting Information [Line Items]
Total sales	419	453
Services | Freight Segment
Segment Reporting Information [Line Items]
Total sales	714	863
Equipment | Freight Segment
Segment Reporting Information [Line Items]
Total sales	726	476
Components | Freight Segment
Segment Reporting Information [Line Items]
Total sales	357	381
Digital Intelligence | Freight Segment
Segment Reporting Information [Line Items]
Total sales	318	181
Original Equipment Manufacturer | Transit Segment
Segment Reporting Information [Line Items]
Total sales	381	322
Aftermarket | Transit Segment
Segment Reporting Information [Line Items]
Total sales	$ 454	$ 387