Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Basic earnings per share:
Net earnings attributable to BorgWarner Inc.	$ 212.0	$ 164.4	$ 401.2	$ 328.5
Weighted average shares of common stock outstanding	210,572	215,735	211,084	216,562
Basic earnings per share of common stock	$ 1.01	$ 0.76	$ 1.90	$ 1.52
Diluted earnings per share:
Net earnings attributable to BorgWarner Inc.	$ 212.0	$ 164.4	$ 401.2	$ 328.5
Weighted average shares of common stock outstanding	210,572	215,735	211,084	216,562
Effect of stock-based compensation	906	928	773	839
Weighted average shares of common stock outstanding including dilutive shares	211,478	216,663	211,857	217,401
Diluted earnings per share of common stock	$ 1.00	$ 0.76	$ 1.89	$ 1.51