Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement of Comprehensive Income [Abstract]
Net earnings attributable to BorgWarner Inc.	$ 174.1	$ 120.6	$ 316.1	$ 278.6
Foreign currency translation adjustments	(5.0)	(90.7)	(89.8)	(45.9)
Hedge instruments	2.5	1.4	13.6	11.0
Defined benefit postretirement plans	(3.4)	(1.0)	(9.2)	(2.6)
Other	0.5	0.5	0.5	0.5
Total other comprehensive income (loss) attributable to BorgWarner Inc.	1.4	(87.8)	(66.5)	(31.8)
Comprehensive income attributable to BorgWarner Inc.	175.5	32.8	249.6	246.8
Comprehensive (loss) income attributable to the noncontrolling interest	(1.1)	(0.8)	(2.3)	0.1
Comprehensive income	$ 174.4	$ 32.0	$ 247.3	$ 246.9