Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings attributable to BorgWarner Inc.		$ 212.0	$ 164.4	$ 401.2	$ 328.5
Other comprehensive income (loss)
Foreign currency translation adjustments		73.4	(54.5)	122.4	13.9
Hedge instruments	[1]	(2.3)	1.7	(3.5)	3.4
Defined benefit postretirement plans	[1]	(4.5)	0.6	(4.4)	0.4
Other	[1]	1.2	(0.8)	1.2	(1.3)
Total other comprehensive income (loss) attributable to BorgWarner Inc.		67.8	(53.0)	115.7	16.4
Comprehensive income attributable to BorgWarner Inc.		279.8	111.4	516.9	344.9
Comprehensive (loss) income attributable to the noncontrolling interest		(0.6)	(1.5)	3.4	0.1
Comprehensive income		$ 279.2	$ 109.9	$ 520.3	$ 345.0

[1] Net of income taxes.