Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revenue from External Customer [Line Items]
Changes in contract estimates related to projects in progress	$ 2.8	$ 5.5
Transferred over Time | Product Concentration Risk | Revenue from Contract with Customer Benchmark
Revenue from External Customer [Line Items]
Concentration risk, percentage	94.00%	92.00%
Transferred at Point in Time | Product Concentration Risk | Revenue from Contract with Customer Benchmark
Revenue from External Customer [Line Items]
Concentration risk, percentage	6.00%	8.00%