Guarantor Subsidiaries Financial Information - Condensed Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Condensed Financial Statements, Captions [Line Items]
Net sales	$ 932,253	$ 723,601	$ 1,848,287	$ 1,495,632
Cost of sales	(658,290)	(486,212)	(1,304,617)	(1,003,063)
Gross profit	273,963	237,389	543,670	492,569
Total operating expenses	(160,262)	(104,105)	(315,111)	(217,104)
Income from operations	113,701	133,284	228,559	275,465
Interest expense, net	(15,420)	(4,969)	(33,132)	(9,840)
Other income (expense), net	(1,552)	(1,229)	767	(1,075)
Equity earnings (loss)	0	0	0	0
Income from operations before income taxes	96,729	127,086	196,194	264,550
Income tax expense	(24,569)	(36,601)	(52,030)	(79,902)
Net income	72,160	90,485	144,164	184,648
Less: Net (gain) loss attributable to noncontrolling interest	(135)	0	1,750	0
Net income attributable to Wabtec shareholders	72,025	90,485	145,914	184,648
Comprehensive income attributable to Wabtec shareholders	219,125	49,236	340,967	171,021
Elimination
Condensed Financial Statements, Captions [Line Items]
Net sales	(32,487)	(101,033)	(64,097)	(78,886)
Cost of sales	23,808	63,754	48,004	49,071
Gross profit	(8,679)	(37,279)	(16,093)	(29,815)
Total operating expenses	0	0	0	0
Income from operations	(8,679)	(37,279)	(16,093)	(29,815)
Interest expense, net	0	0	0	0
Other income (expense), net	0	0	0	0
Equity earnings (loss)	(135,150)	(155,049)	(215,377)	(306,769)
Income from operations before income taxes	(143,829)	(192,328)	(231,470)	(336,584)
Income tax expense	0	0	0	0
Net income	(143,829)	(192,328)	(231,470)	(336,584)
Less: Net (gain) loss attributable to noncontrolling interest	0	0	0	0
Net income attributable to Wabtec shareholders	(143,829)	(192,328)	(231,470)	(336,584)
Comprehensive income attributable to Wabtec shareholders	(143,829)	(192,328)	(231,470)	(336,584)
Parent
Condensed Financial Statements, Captions [Line Items]
Net sales	137,708	161,632	282,251	338,619
Cost of sales	(100,311)	(118,079)	(199,262)	(247,160)
Gross profit	37,397	43,553	82,989	91,459
Total operating expenses	(32,954)	(29,063)	(57,247)	(66,938)
Income from operations	4,443	14,490	25,742	24,521
Interest expense, net	(18,732)	(7,085)	(33,343)	(13,754)
Other income (expense), net	(10,228)	223	2,854	11,040
Equity earnings (loss)	96,944	108,929	165,229	221,950
Income from operations before income taxes	72,427	116,557	160,482	243,757
Income tax expense	(402)	(26,074)	(14,567)	(59,108)
Net income	72,025	90,483	145,915	184,649
Less: Net (gain) loss attributable to noncontrolling interest	0	0	0	0
Net income attributable to Wabtec shareholders	72,025	90,483	145,915	184,649
Comprehensive income attributable to Wabtec shareholders	72,921	90,182	147,668	183,369
Guarantors
Condensed Financial Statements, Captions [Line Items]
Net sales	250,065	349,763	508,777	606,676
Cost of sales	(159,789)	(221,854)	(327,395)	(374,815)
Gross profit	90,276	127,909	181,382	231,861
Total operating expenses	(30,072)	(30,596)	(59,944)	(62,948)
Income from operations	60,204	97,313	121,438	168,913
Interest expense, net	2,251	1,596	4,411	3,321
Other income (expense), net	(617)	611	(1,877)	(3,870)
Equity earnings (loss)	38,206	46,120	50,148	84,819
Income from operations before income taxes	100,044	145,640	174,120	253,183
Income tax expense	124	(947)	(17)	(1,947)
Net income	100,168	144,693	174,103	251,236
Less: Net (gain) loss attributable to noncontrolling interest	157	0	157	0
Net income attributable to Wabtec shareholders	100,325	144,693	174,260	251,236
Comprehensive income attributable to Wabtec shareholders	100,326	144,691	174,261	251,236
Non-Guarantors
Condensed Financial Statements, Captions [Line Items]
Net sales	576,967	313,239	1,121,356	629,223
Cost of sales	(421,998)	(210,033)	(825,964)	(430,159)
Gross profit	154,969	103,206	295,392	199,064
Total operating expenses	(97,236)	(44,446)	(197,920)	(87,218)
Income from operations	57,733	58,760	97,472	111,846
Interest expense, net	1,061	520	(4,200)	593
Other income (expense), net	9,293	(2,063)	(210)	(8,245)
Equity earnings (loss)	0	0	0	0
Income from operations before income taxes	68,087	57,217	93,062	104,194
Income tax expense	(24,291)	(9,580)	(37,446)	(18,847)
Net income	43,796	47,637	55,616	85,347
Less: Net (gain) loss attributable to noncontrolling interest	(292)	0	1,593	0
Net income attributable to Wabtec shareholders	43,504	47,637	57,209	85,347
Comprehensive income attributable to Wabtec shareholders	$ 189,707	$ 6,691	$ 250,508	$ 73,000