REPORTING SEGMENTS AND RELATED INFORMATION - Earnings before interest and income taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information
Segment Adjusted Operating Income	$ 452	$ 533
Corporate, including stock-based compensation	63	69
Merger, acquisition and divestiture expense	23	13
Intangible asset amortization expense	23	20
Restructuring expense	15	30
Gain on sale of business	(24)	0
Net gain on insurance recovery for property damage	0	(2)
Equity in affiliates’ earnings, net of tax	(8)	(12)
Unrealized loss on equity securities	39	272
Interest expense, net	15	18
Other postretirement income	(9)	(11)
Earnings before income taxes and noncontrolling interest	315	136
Provision for income taxes	91	42
Net earnings	224	94
Net earnings attributable to noncontrolling interest, net of tax	24	29
Net earnings attributable to BorgWarner Inc.	200	65
Air Management
Segment Reporting Information
Segment Adjusted Operating Income	257	329
e-Propulsion & Drivetrain
Segment Reporting Information
Segment Adjusted Operating Income	119	149
Fuel Injection
Segment Reporting Information
Segment Adjusted Operating Income	52	34
Aftermarket
Segment Reporting Information
Segment Adjusted Operating Income	$ 24	$ 21