Fair Value Measurements and Derivative Instruments (Tables)

3 Months Ended

Dec. 31, 2022

Derivative Instruments Gain Loss [Line Items]

Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

The following tables summarize the financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2022 and September 30, 2022:

	December 31, 2022
	Carrying Value		Level 1		Level 2		Level 3
Other assets:
Investments held by Rabbi Trust	$	10.8	$	10.8	$	—	$	—
Total assets	$	10.8	$	10.8	$	-	$	—
Other liabilities:
Obligation to Rabbi Trust	$	10.8	$	10.8	$	—	$	—
Total liabilities	$	10.8	$	10.8	$	—	$	—

	September 30, 2022
	Carrying Value		Level 1		Level 2		Level 3
Other assets:
Investments held by Rabbi Trust	$	10.6	$	10.6	$	—	$	—
Interest rate swap contracts		3.0		—		3.0		—
Total Assets	$	13.6	$	10.6	$	3.0	$	—
Other liabilities:
Obligation to Rabbi Trust		10.6		10.6		—		—
Total Liabilities	$	10.6	$	10.6	$	—	$	—

Interest Rate Swaps

Derivative Instruments Gain Loss [Line Items]

Summary of Effects on Consolidated Financial Statements of Designated As Cash Flow Hedges

The effects on the consolidated financial statements of the interest rate swaps which were designated as cash flow hedges were as follows:

	Three Months Ended December 31,
	2022		2021
Income recognized in Other comprehensive (loss) income	$	—	$	1.1
Net income (loss) reclassified from Accumulated other comprehensive (loss) income into Interest expense		3.0		(0.8	)

Fuel Swap Contracts

Derivative Instruments Gain Loss [Line Items]

Summary of Effects on Consolidated Financial Statements of Designated As Cash Flow Hedges

The effects on the consolidated financial statements of the fuel swaps which were designated as cash flow hedges were as follows:

	Three Months Ended December 31,
	2022		2021
Income recognized in Other comprehensive (loss) income	$	—	$	0.2
Net gain reclassified from Accumulated other comprehensive (loss) income into Cost of services provided		—		1.5