Reporting Segments and Related Information - Quarterly Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Asbestos-related charge									$ 703.6	$ 0.0	$ 0.0
Net sales	$ 2,259.0	$ 2,214.2	$ 2,329.2	$ 2,268.6	$ 2,123.1	$ 1,884.0	$ 2,031.9	$ 1,984.2	9,071.0	8,023.2	8,305.1
Cost of sales	1,758.0	1,743.1	1,832.5	1,804.3	1,676.2	1,485.8	1,602.9	1,555.2	7,137.9	6,320.1	6,548.7
Gross profit	501.0	471.1	496.7	464.3	446.9	398.2	429.0	429.0	1,933.1	1,703.1	1,756.4
Selling, general and administrative expenses	217.1	209.7	202.3	188.4	178.4	148.0	167.4	168.2	817.5	662.0	698.9
Other expense, net	741.9	111.1	25.0	11.7	68.0	13.1	19.1	1.2	889.7	101.4	93.8
Operating income	(458.0)	150.3	269.4	264.2	200.5	237.1	242.5	259.6	225.9	939.7	963.7
Equity in affiliates’ earnings, net of tax	(11.3)	(12.4)	(10.1)	(9.1)	(11.7)	(8.7)	(11.1)	(8.5)	(42.9)	(40.0)	(47.3)
Interest income	(1.6)	(1.6)	(1.5)	(1.6)	(2.2)	(2.0)	(1.6)	(1.7)	(6.3)	(7.5)	(5.5)
Interest expense and finance charges	19.5	22.4	21.4	21.3	17.8	15.0	17.6	10.0	84.6	60.4	36.4
Earnings before income taxes and noncontrolling interest	(464.6)	141.9	259.6	253.6	196.6	232.8	237.6	259.8	190.5	926.8	980.1
Provision for income taxes	(183.1)	48.8	84.2	80.4	61.2	66.9	80.2	72.1	30.3	280.4	292.6
Net earnings	(281.5)	93.1	175.4	173.2	135.4	165.9	157.4	187.7	160.2	646.4	687.5
Net earnings attributable to the noncontrolling interest, net of tax	11.8	9.8	11.0	9.1	10.1	8.5	9.3	8.8	41.7	36.7	31.7
Net earnings attributable to BorgWarner Inc.	$ (293.3)	$ 83.3	$ 164.4	$ 164.1	$ 125.3	$ 157.4	$ 148.1	$ 178.9	$ 118.5	$ 609.7	$ 655.8
Earnings per share — basic	$ (1.39)	$ 0.39	$ 0.76	$ 0.75	$ 0.57	$ 0.70	$ 0.66	$ 0.79	$ 0.55	$ 2.72	$ 2.89
Earnings per share — diluted	$ (1.39)	$ 0.39	$ 0.76	$ 0.75	$ 0.56	$ 0.70	$ 0.65	$ 0.79	$ 0.55	$ 2.70	$ 2.86
Pension settlement loss									$ 0.0	$ 25.7	$ 3.1
Merger and acquisition expense	$ 4.8	$ 5.9	$ 7.2	$ 5.8	$ 17.9	$ 3.9			23.7	21.8	0.0
Tax benefits associated with asbestos-related charge	263.0								263.0
Tax (expenses) benefits associated with loss on divestiture	(4.9)								22.7
Tax benefits associated with intangible asset impairment	4.4								4.4
Effective income tax rate reconciliation, asset impairment expense		27.6
Tax expense on gain from customer contract expiration			(2.6)						(2.2)
Tax expense global realignment plan						4.5	$ 10.3
Restructuring expense		1.3	19.2	6.4	24.4	6.3	10.5	$ 9.4	26.9	65.7	90.8
Tax impact of other tax settlements							3.9
Intangible asset impairment									12.6	0.0	10.3
Loss on divestiture	20.6								127.1	0.0	0.0
Tax benefit associated with restructuring		0.5	4.4	1.0	0.4	0.7	2.2	1.2	6.0	3.7	15.3
Tax benefits related to partial reversal of a gain with customer contract expiration		0.4
Tax benefit on intangible asset impairment											0.4
Other tax benefits										9.0	1.1
Tax impact of other tax adjustments	4.9	2.4	$ 0.3	$ 1.0	$ 7.7	0.4	1.3	2.4	8.6	9.9
Asset Impairment Charges		$ 106.5
Tax benefit associated with merger and acquisition expense										3.8
Gain on previously held equity interest									$ 0.0	10.8	0.0
Corporate and Other [Member]
Restructuring expense						$ 3.0	$ 9.4	$ 2.7		$ 12.5	$ 12.0
U.S. Plans:
Loss on divestiture	$ 20.6