Revenue - Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Contract assets	$ 88,351	$ 88,351	$ 54,199
Contract liabilities	(79,857)	(79,857)	(42,433)
Net contract asset	8,494	8,494	11,766
Revenue recognized related to contract liabilities	2,500	39,100
Retention amounts included in accounts receivable	6,900	6,900	$ 9,600
Retained amount expected to be collected in the next twelve months	6,000	6,000
Retained amount expected to be collected	$ 900	$ 900