CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Net sales	$ 2,534	$ 2,492	$ 6,239	$ 7,609
Cost of sales	2,017	1,968	5,101	6,053
Gross profit	517	524	1,138	1,556
Selling, general and administrative expenses	204	230	601	668
Other expense, net	29	18	142	63
Operating income	284	276	395	825
Equity in affiliates’ earnings, net of tax	(3)	(7)	(10)	(25)
Interest income	(3)	(4)	(8)	(9)
Interest expense	20	15	50	43
Other postretirement (income) expense	(2)	(1)	(5)	26
Earnings before income taxes and noncontrolling interest	272	273	368	790
Provision for income taxes	143	66	186	230
Net earnings	129	207	182	560
Net earnings attributable to the noncontrolling interest, net of tax	18	13	40	34
Net earnings attributable to BorgWarner Inc.	$ 111	$ 194	$ 142	$ 526
Earnings per share - basic (in dollar per share)	$ 0.54	$ 0.94	$ 0.69	$ 2.56
Earnings per share - diluted (in dollar per share)	$ 0.53	$ 0.94	$ 0.69	$ 2.54
Weighted average shares outstanding:
Basic (in shares)	206.0	205.3	205.9	205.9
Diluted (in shares)	207.3	206.3	206.7	206.8