Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Net income attributable to Wabtec shareholders	$ 94,163	$ 96,164
Less: dividends declared - common shares and non-vested restricted stock	(7,355)	(5,781)
Undistributed earnings	$ 86,808	$ 90,383
Percentage allocated to common shareholders	99.70%	99.60%
Undistributed earnings allocated to common shareholders	$ 86,548	$ 90,021
Add: dividends declared - common shares	7,332	5,759
Numerator for basic and diluted earnings per common share	$ 93,880	$ 95,780
Basic weighted average common shares outstanding (in shares)	91,258	96,243
Assumed conversion of dilutive stock-based compensation plans (in shares)	891	1,142
Denominator for diluted earnings per common share - adjusted weighted average shares and assumed conversion (in shares)	92,149	97,385
Basic earnings per share (in dollars per share)	$ 1.03	$ 1.00
Diluted earnings per share, as reported (in dollars per share)	$ 1.02	$ 0.99
Basic weighted-average common shares outstanding and non-vested restricted stock expected to vest (in shares)	91,543	96,607