INCOME TAXES - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Oct. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Effective income tax rate reconciliation (in percent)		41.00%	37.00%	18.00%
Effective income tax rate reconciliation, tax credit, foreign, amount				$ (22)
Tax benefit associated with restructuring			$ 19	15
Effective income tax rate reconciliation, global realignment plan			11
Effective income tax rate reconciliation, other adjustments, amount			8
Effective income tax rate reconciliation, deduction, other postretirement expense, amount			6
Tax benefits associated with asbestos-related adjustments				6
Tax benefit associated with asset impairment expense				8
Tax expense on gain from customer contract expiration				1
Tax expense on gain on commercial settlement				6
Increase (decrease) in deferred tax assets due to final SAB 118 adjustments				13
Increase (decrease) in deferred tax assets, executive compensation, final SAB 118 adjustments				9
Income tax expense, one-time transition tax measurement period adjustment due to change of tax law				8
Decrease in deferred tax liability, indefinite reinvestment assertion, measurement period adjustments due to change of law				7
Effective rate reconciliation measurement period adjustments due to the Tax act				13
Interest expense		$ 21	15
Payment for penalties and interest accrued		69	46
Unrecognized tax benefits that would impact effective tax rate		263
Unrecognized tax benefits		231	146	$ 120	$ 92
Net operating loss and capital loss carryforwards		656	70
Operating loss carryforwards, state and local		$ 614
Income tax holiday, expiration term of subsidiaries		3 years
Deferred tax liabilities, undistributed foreign earnings		$ 156	56
Deferred tax liability not reported, undistributed earnings of foreign subsidiaries		1,100
Amount of unrecognized deferred tax liability		70
Other current liabilities
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits		66
BorgWarner Morse TEC LLC
Operating Loss Carryforwards [Line Items]
Tax expense on derecognition of subsidiary	$ 173
Non-U.S. Tax Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		2,400
Operating loss carryforwards, subject to expiration		1,900
Operating loss carryforwards, not subject to expiration		522
Operating loss carryforwards, valuation allowance		505
Net operating loss and capital loss carryforwards		2,400
Income tax holiday, aggregate dollar amount		36	$ 26
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, valuation allowance		17
Tax credit carryforwards, other		28
Tax credit carryforward, valuation allowance		$ 26