Earnings Per Share (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Basic earnings per share:
Net earnings attributable to BorgWarner Inc.	$ 159.1	$ 142.0
Weighted average shares of common stock outstanding	227,430	230,372
Basic earnings per share of common stock	$ 0.70	$ 0.62
Diluted earnings per share:
Net earnings attributable to BorgWarner Inc.	159.1	142.0
Adjustment for net interest expense on convertible notes	0	0
Diluted net earnings attributable to BorgWarner Inc.	$ 159.1	$ 142.0
Weighted average shares of common stock outstanding	227,430	230,372
Effect of 3.50% convertible senior notes	0	0
Effect of warrant	0	0
Effect of stock-based compensation	1,897	2,758
Weighted average shares of common stock outstanding including dilutive shares	229,327	233,130
Diluted earnings per share of common stock	$ 0.69	$ 0.61
Call Option [Member]
Diluted earnings per share:
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	0