Accounting Policies - Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Cost of sales	$ 486,212	$ 579,264	$ 1,003,063	$ 1,142,503
Income from Operations	127,086	149,932	264,550	291,180
Income tax expense	(36,601)	(48,428)	(79,902)	(93,512)
Interest expense, net	(4,969)	(4,041)	(9,840)	(8,347)
Net income attributable to Wabtec shareholders	90,485	$ 101,504	184,648	$ 197,668
Reclassification out of Accumulated Other Comprehensive Income | Pension and post retirement benefit plans
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Income from Operations	549		1,284
Income tax expense	(157)		(388)
Net income attributable to Wabtec shareholders	392		896
Reclassification out of Accumulated Other Comprehensive Income | Amortization of initial net obligation and prior service cost
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Cost of sales	(422)		(807)
Reclassification out of Accumulated Other Comprehensive Income | Amortization of net loss
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Cost of sales	971		2,091
Reclassification out of Accumulated Other Comprehensive Income | Derivative contracts
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Income tax expense	(130)		(280)
Interest expense, net	453		927
Net income attributable to Wabtec shareholders	$ 323		$ 647