BorgWarner Inc. and Consolidated Subsidiaries Consolidated Statements of Equity - USD ($) $ in Millions	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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury Stock, Common, Shares					(27,062,236)
Beginning Balance at Dec. 31, 2015			$ 2.5	$ 1,109.7	$ (1,158.4)	$ 3,733.6	$ (610.2)	$ 77.8
Beginning Balance, shares at Dec. 31, 2015			246,387,057
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared						(113.4)		(26.0)
Stock incentive plans				(19.4)					$ 32.4
Net issuance for executive stock plan				12.8						$ 0.0
Net issuance of restricted stock				1.2							$ 19.2
Treasury stock reissued, shares									793,230	0	414,464
Purchase of treasury stock					$ (274.8)
Business divestiture								(4.8)
Purchases of treasury stock, shares					(8,269,550)
Net earnings attributable to BorgWarner Inc.	$ 595.0					595.0
Net earnings attributable to the noncontrolling interest, net of tax	41.7							41.7
Other comprehensive income (loss)	(111.9)						(111.9)
Other comprehensive (loss) income attributable to the noncontrolling interest	$ (5.1)	[1]						(5.1)
Ending Balance at Dec. 31, 2016			$ 2.5	1,104.3	$ (1,381.6)	4,215.2	(722.1)	83.6
Ending Balance, shares at Dec. 31, 2016			246,387,057
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.53
Treasury Stock, Common, Shares					(34,124,092)
Dividends declared						(124.1)		(29.3)
Stock incentive plans				(10.6)					$ 18.9
Net issuance for executive stock plan				21.0						$ 2.7
Net issuance of restricted stock				4.0							$ 14.6
Treasury stock reissued, shares									473,419	73,935	402,184
Purchase of treasury stock					$ (100.0)
Purchases of treasury stock, shares					(2,399,710)
Net earnings attributable to BorgWarner Inc.	$ 439.9					439.9
Net earnings attributable to the noncontrolling interest, net of tax	43.4							43.4
Other comprehensive income (loss)	232.1						232.1
Other comprehensive (loss) income attributable to the noncontrolling interest	11.4	[1]						11.4
Ending Balance at Dec. 31, 2017	$ 3,825.9		$ 2.5	1,118.7	$ (1,445.4)	4,531.0	(490.0)	109.1
Ending Balance, shares at Dec. 31, 2017			246,387,057
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.59
Treasury Stock, Common, Shares					(35,574,264)
Adoption of accounting standards						15.9	(14.0)
Dividends declared						(141.5)		(35.8)
Net issuance for executive stock plan				17.5						$ 4.5
Net issuance of restricted stock				9.6							$ 6.1
Treasury stock reissued, shares										154,642	284,946
Purchase of treasury stock					$ (150.0)
Purchases of treasury stock, shares					(3,037,447)
Net earnings attributable to BorgWarner Inc.	$ 930.7					930.7
Net earnings attributable to the noncontrolling interest, net of tax	53.9							53.9
Other comprehensive income (loss)	(170.1)						(170.1)
Other comprehensive (loss) income attributable to the noncontrolling interest	(7.9)	[1]						(7.9)
Ending Balance at Dec. 31, 2018	$ 4,344.8		$ 2.5	$ 1,145.8	$ (1,584.8)	$ 5,336.1	$ (674.1)	$ 119.3
Ending Balance, shares at Dec. 31, 2018			246,387,057
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.68
Treasury Stock, Common, Shares					(38,172,123)

[1] *Net of income taxes.