Revenue - Performance Obligations and Contract Estimates (Details) $ in Millions	9 Months Ended
	Jun. 30, 2023 USD ($) project	Jun. 30, 2022 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Standard assurance warranty, period	1 year
Remaining performance obligation, amount	$ 1,300.0
Changes in contract estimates related to projects in progress	$ 13.2	$ 5.9
Projects cancelled | project	2
Change in contract estimates due to project cancellations	$ 3.4
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 690.0
Remaining performance obligation, expected timing of satisfaction, period	12 months