Supporting Financial Information - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2023
Finite-Lived Intangible Assets [Line Items]
Amortization expense of intangible assets	$ 4.1	$ 2.2
Intangible assets, remaining amortization period	8 years 1 month 6 days
Depreciation	$ 0.1	$ 0.2
Customer contracts and related customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets, remaining amortization period			8 years
Backlog
Finite-Lived Intangible Assets [Line Items]
Intangible assets, remaining amortization period			8 years 3 months 18 days
Trade name
Finite-Lived Intangible Assets [Line Items]
Intangible assets, remaining amortization period			8 years 4 months 24 days
Covenants not to compete
Finite-Lived Intangible Assets [Line Items]
Intangible assets, remaining amortization period			5 years 9 months 18 days