BorgWarner Inc. and Consolidated Subsidiaries Consolidated Statements of Equity (USD $) In Millions, except Share data, unless otherwise specified	Total	Issued common stock	Capital in excess of par value	Common stock held in treasury	Retained earnings	Accumulated other comprehensive income (loss)	Noncontrolling interests	Employee Stock Option [Member] Common stock held in treasury	Performance Shares [Member] Common stock held in treasury	Restricted Stock [Member] Common stock held in treasury
Beginning Balance at Dec. 31, 2011		$ 1.2	$ 1,134.3	$ (707.1)	$ 2,110.3	$ (150.8)	$ 65.1
Beginning Balance, shares at Dec. 31, 2011		242,631,410		(25,602,486)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared							(18.9)
Stock incentive plans			52.0
Stock incentive plans, shares	1,568,000	1,555,850
Executive stock plan			39.3
Executive stock plan, shares		1,076,360
Net issuance of restricted stock			21.2	(18.1)
Net issuance of restricted stock, shares		(782,698)
Treasury stock reissued, value	338.5			338.5
Treasury stock reissued, shares	(9,800,000)			9,709,308
Purchase of treasury stock				(295.9)
Purchases of treasury stock, shares				(8,311,388)
Net earnings attributable to BorgWarner Inc.	500.9				500.9
Net earnings attributable to the noncontrolling interest, net of tax	21.5						(21.5)
Other comprehensive income (loss)	29.5					29.5
Comprehensive (loss) income attributable to the noncontrolling interest	(2.8)						2.8
Shares Paid for Tax Withholding for Share Based Compensation				(482,500)
Convertible bond settlement, shares				22,765,542
Convertible bond settlement			(243.5)
Conversion of convertible securities, value of shares issued				617.3
Treasury stock received from bond hedge, shares	(13,000,000)			(12,979,396)
Adjustments to additional paid in capital, bond hedge	503.9		503.9
Treasury stock received from bond hedge, value	(503.9)			(503.9)
Adjustments to additional paid in capital, warrant	338.5		(338.5)
Adjustments to capital in excess of par value			(8.0)
Purchase of subsidiary shares from noncontrolling interest							(7.0)
Ending Balance at Dec. 31, 2012		1.2	1,160.7	(569.2)	2,611.2	(121.3)	63.5
Ending Balance, shares at Dec. 31, 2012		246,046,318		(14,900,920)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared					(56.8)		(20.1)
Stock incentive plans			(2.9)					35.9
Stock incentive plans, shares	870,000	8,200
Executive stock plan			(33.7)						44.5
Net issuance of restricted stock			(2.2)							(12.9)
Net issuance of restricted stock, shares		(367,375)
Treasury stock reissued, shares								861,866	644,638	148,485
Purchase of treasury stock				(225.5)
Purchases of treasury stock, shares				(5,243,106)
Net earnings attributable to BorgWarner Inc.	624.3				624.3
Net earnings attributable to the noncontrolling interest, net of tax	26.7						26.7
Other comprehensive income (loss)	107.3					107.3
Comprehensive (loss) income attributable to the noncontrolling interest	(1.7)						1.7
Stock split		1.3
Dividends, stock split					(1.3)
Convertible bond settlement, shares	(22,800,000)
Convertible bond settlement	243.5
Conversion of convertible securities, value of shares issued	617.3
Ending Balance at Dec. 31, 2013	3,632.4	2.5	1,121.9	(727.2)	3,177.4	(14.0)	71.8
Ending Balance, shares at Dec. 31, 2013		246,421,893		(18,489,037)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared					(116.1)		(24.9)
Stock incentive plans			5.4					11.5
Stock incentive plans, shares	283,000
Executive stock plan			(13.3)						24.7
Net issuance of restricted stock			(1.6)							(1.3)
Net issuance of restricted stock, shares		31,273
Treasury stock reissued, shares								283,090	336,883	326,074
Purchase of treasury stock				(139.9)
Purchases of treasury stock, shares				(2,417,547)
Net earnings attributable to BorgWarner Inc.	655.8				655.8
Net earnings attributable to the noncontrolling interest, net of tax	31.7						31.7
Other comprehensive income (loss)	(369.6)					(369.6)
Comprehensive (loss) income attributable to the noncontrolling interest	3.9						(3.9)
Ending Balance at Dec. 31, 2014	$ 3,690.9	$ 2.5	$ 1,112.4	$ (832.2)	$ 3,717.1	$ (383.6)	$ 74.7
Ending Balance, shares at Dec. 31, 2014		246,390,620		(19,960,537)