CONTINGENCIES - Impacts to the Consolidated Balance Sheet (Details) - USD ($) $ in Millions		12 Months Ended
	Oct. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Accounts payable and accrued expenses		$ 0	$ 172	$ 0
BorgWarner Morse TEC LLC
Loss Contingencies [Line Items]
Cash and cash equivalents	$ (172)	(172)
Receivables, net		(9)
Investments and other long-term receivables		(371)
Other non-current assets		(223)
Accounts payable and accrued expenses		7
Asbestos-related and environmental liabilities		772
Gain on derecognition of subsidiary, net	$ 4	$ 4