Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2012

Earnings Per Share [Abstract]

Schedule of Earnings per Share reconciliation [Text Block]

The following table reconciles the numerators and denominators used to calculate basic and diluted earnings per share of common stock:

	Year Ended December 31,
(in millions except per share amounts)	2012		2011		2010
Basic earnings per share:
Net earnings attributable to BorgWarner Inc.	$	500.9	$	550.1	$	377.4
Weighted average shares of common stock outstanding	112.652		109.229		114.155
Basic earnings per share of common stock	$	4.45	$	5.04	$	3.31
Diluted earnings per share:
Net earnings attributable to BorgWarner Inc.	$	500.9	$	550.1	$	377.4
Adjusted for net interest expense on convertible notes	5.8		21.5		20.4
Diluted net earnings attributable to BorgWarner Inc.	$	506.7	$	571.6	$	397.8
Weighted average shares of common stock outstanding	112.652		109.229		114.155
Effect of 3.50% convertible senior notes	3.322		11.389		11.389
Effect of warrant	3.400		5.215		1.464
Effect of stock-based compensation	2.003		2.635		2.567
Total dilutive effect on weighted average shares of common stock outstanding	8.725		19.239		15.420
Weighted average shares of common stock outstanding including dilutive shares	121.377		128.468		129.575
Diluted earnings per share of common stock	$	4.17	$	4.45	$	3.07
Total anti-dilutive shares:
Call options	1.939		6.141		2.836