Guarantor Subsidiaries Income Statement (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Condensed Financial Statements Captions [Line Items]
Net sales	$ 615,510		$ 583,309
Cost of sales	(432,622)		(413,928)
Gross (loss) profit	182,888		169,381
Operating expenses	(79,221)		(75,271)
Operating (loss) profit	103,667		94,110
Interest expense, net	(3,614)		(3,724)
Other (expense) income, net	(581)		(114)
Income from operations before income taxes	99,472		90,272
Income tax expense	(29,859)		(31,011)
Net income attributable to Wabtec shareholders	69,613		59,261
Comprehensive income (loss) attributable to Wabtec shareholders	43,873		70,486
Parent Company
Condensed Financial Statements Captions [Line Items]
Cost of sales	487		(55)
Gross (loss) profit	487		(55)
Operating expenses	(15,174)		(17,201)
Operating (loss) profit	(14,687)		(17,256)
Interest expense, net	(4,916)		(5,462)
Other (expense) income, net	10,896		7,832
Equity earnings	101,415		93,698
Income from operations before income taxes	92,708		78,812
Income tax expense	(23,095)		(19,551)
Net income attributable to Wabtec shareholders	69,613		59,261
Comprehensive income (loss) attributable to Wabtec shareholders	71,799		59,585
Guarantor Subsidiaries
Condensed Financial Statements Captions [Line Items]
Net sales	418,035		414,650
Cost of sales	(270,545)		(270,578)
Gross (loss) profit	147,490		144,072
Operating expenses	(38,319)		(38,984)
Operating (loss) profit	109,171		105,088
Interest expense, net	1,284		1,178
Other (expense) income, net	(3,776)		(4,303)
Equity earnings	17,700		12,387
Income from operations before income taxes	124,379		114,350
Income tax expense	(3,426)		(3,593)
Net income attributable to Wabtec shareholders	120,953		110,757
Comprehensive income (loss) attributable to Wabtec shareholders	120,953		110,757
Non-Guarantor Subsidiaries
Condensed Financial Statements Captions [Line Items]
Net sales	237,160		210,053
Cost of sales	(182,142)		(160,269)
Gross (loss) profit	55,018		49,784
Operating expenses	(25,728)		(19,086)
Operating (loss) profit	29,290		30,698
Interest expense, net	18		560
Other (expense) income, net	(7,701)		(3,643)
Income from operations before income taxes	21,607		27,615
Income tax expense	(3,338)		(7,867)
Net income attributable to Wabtec shareholders	18,269		19,748
Comprehensive income (loss) attributable to Wabtec shareholders	(9,657)		30,649
Elimination
Condensed Financial Statements Captions [Line Items]
Net sales	(39,685)	[1]	(41,394)	[1]
Cost of sales	19,578	[1]	16,974	[1]
Gross (loss) profit	(20,107)	[1]	(24,420)	[1]
Operating (loss) profit	(20,107)	[1]	(24,420)	[1]
Equity earnings	(119,115)	[1]	(106,085)	[1]
Income from operations before income taxes	(139,222)	[1]	(130,505)	[1]
Net income attributable to Wabtec shareholders	(139,222)	[1]	(130,505)	[1]
Comprehensive income (loss) attributable to Wabtec shareholders	$ (139,222)	[1]	$ (130,505)	[1]

[1] Includes elimination of gross profit realized with certain intercompany transactions between Guarantor and Non-Guarantor subsidiaries.