CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income attributable to Wabtec shareholders	$ 124.8	$ 86.8	$ 237.2	$ 198.4
Foreign currency translation gain (loss)	33.8	29.2	(27.9)	(152.2)
Unrealized gain (loss) on derivative contracts	0.5	(9.1)	(7.4)	(1.0)
Unrealized (loss) gain on pension benefit plans and post-retirement benefit plans	(1.1)	0.7	(4.4)	(2.9)
Other comprehensive income (loss) before tax	33.2	20.8	(39.7)	(156.1)
Income tax benefit related to components of other comprehensive income (loss)	0.0	2.0	3.0	0.9
Other comprehensive income (loss), net of tax	33.2	22.8	(36.7)	(155.2)
Comprehensive income attributable to Wabtec shareholders	$ 158.0	$ 109.6	$ 200.5	$ 43.2