Stockholder's Equity (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Common Stock, Dividends, Per Share, Declared		$ 0.17	$ 0.17	$ 0.34	$ 0.34
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		$ 4,502		$ 4,502			$ 4,345
Cumulative Effect of New Accounting Principle in Period of Adoption									$ (14)
Net earnings attributable to BorgWarner Inc.		172	$ 272	332	$ 497
Net earnings attributable to the noncontrolling interest, net of tax		10	12	21	24
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		5	(138)	4	(78)
Other comprehensive loss attributable to the noncontrolling interest	[1]	(3)	(6)	(2)	(4)
Common Stock [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		3	3	3	3	$ 3	3	$ 3		$ 3
Additional Paid-in Capital [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		1,116	1,110	1,116	1,110	1,111	1,146	1,102		1,118
Treasury Stock [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		(1,653)	(1,544)	(1,653)	(1,544)	(1,626)	(1,585)	(1,486)		(1,445)
Treasury Stock, Value, Acquired, Cost Method		(31)	(57)	(100)	(114)
Retained Earnings [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		5,598	4,973	5,598	4,973	5,461	5,336	4,736		4,531
Dividends, Common Stock, Cash		(35)	(35)	(70)	(71)
Cumulative Effect of New Accounting Principle in Period of Adoption									16
Net earnings attributable to BorgWarner Inc.		172	272	332	497
AOCI Attributable to Parent [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		(670)	(582)	(670)	(582)	(675)	(674)	(444)		(490)
Cumulative Effect of New Accounting Principle in Period of Adoption									$ (14)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		5	(138)	4	(78)
Noncontrolling Interest [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		108	94	108	94	$ 111	$ 119	$ 105		$ 109
Dividends, Common Stock, Cash		(10)	(17)	(30)	(35)
Net earnings attributable to the noncontrolling interest, net of tax		10	12	21	24
Other comprehensive loss attributable to the noncontrolling interest		(3)	(6)	(2)	(4)
Performance Shares [Member] | Additional Paid-in Capital [Member]
Adjustments to Additional Paid in Capital, Share-based Compensation and Exercise of Stock Options		1	2	(9)	1
Performance Shares [Member] | Treasury Stock [Member]
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures		0	1	7	5
Restricted Stock [Member] | Additional Paid-in Capital [Member]
Adjustments to Additional Paid in Capital, Share-based Compensation and Exercise of Stock Options		4	6	(21)	(9)
Restricted Stock [Member] | Treasury Stock [Member]
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures		$ 4	$ (2)	$ 25	$ 10

[1] Net of income taxes.