Intangible Assets, Goodwill, Acquisitions and Divestitures (Tables)

12 Months Ended

Sep. 30, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets

Intangible assets as of September 30, 2025 and September 30, 2024 consisted of the following:

		September 30, 2025					September 30, 2024
	Estimated Useful Life	Gross Carrying Amount		Accumulated Amortization			Gross Carrying Amount		Accumulated Amortization
Customer relationships	6-21 yrs.	$	715.9	$	(649.4	)	$	715.9	$	(620.1	)
Total intangible assets		$	715.9	$	(649.4	)	$	715.9	$	(620.1	)

Schedule of Future Amortization Expense

Amortization expense is anticipated to be as follows in future years:

Fiscal Year Ended September 30,
2026	$	21.8
2027		15.2
2028		11.1
2029		7.2
2030		3.2
2031 and thereafter		8.0
	$	66.5

Summary of Goodwill

The following is a summary of the goodwill activity for the periods ended September 30, 2024 and September 30, 2025:

	Maintenance Services			Development Services		Total
Balance, September 30, 2023	$	1,803.4		$	218.0	$	2,021.4
Acquisitions (1)		0.1			—		0.1
Divestiture		(5.8	)		—		(5.8	)
Balance, September 30, 2024	$	1,797.7		$	218.0	$	2,015.7
Balance, September 30, 2025	$	1,797.7		$	218.0	$	2,015.7

(1)The acquisitions adjustments include the immaterial impact of foreign currency and other prior year measurement period adjustments during the respective periods.