Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 49.1	$ 34.2	$ 154.8	$ 109.0
Other comprehensive (loss)/gain, net of tax:
Foreign currency translation adjustment	(5.4)	4.0	(5.5)	16.3
Cash flow hedges	(6.8)	0.0	(25.0)	0.0
Other comprehensive (loss)/gain, net of tax	(12.2)	4.0	(30.5)	16.3
Comprehensive income	$ 36.9	$ 38.2	$ 124.3	$ 125.3