Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Basic earnings per share [Abstract]
Weighted average shares of common stock outstanding									224,414	227,150	228,600
Earnings per share — basic	$ 0.57	$ 0.70	$ 0.66	$ 0.79	$ 0.62	$ 0.73	$ 0.84	$ 0.70	$ 2.72	$ 2.89	$ 2.73
Diluted earnings per share [Abstract]
Net earnings attributable to BorgWarner Inc.	$ 125.3	$ 157.4	$ 148.1	$ 178.9	$ 139.9	$ 166.6	$ 190.2	$ 159.1	$ 609.7	$ 655.8	$ 624.3
Effect of stock-based compensation									1,234	1,774	2,737
Weighted average shares of common stock outstanding including dilutive shares									225,648	228,924	231,337
Earnings per share — diluted	$ 0.56	$ 0.70	$ 0.65	$ 0.79	$ 0.61	$ 0.73	$ 0.83	$ 0.69	$ 2.70	$ 2.86	$ 2.70