Restructuring (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Restructuring Reserve
Balance, Beginning of Period	$ 7.4
Restructuring Charges (Adjustments)	0.9	$ 0.8
Cash payments	(0.8)
Non-cash charges	0.0
Balance, End of Period	7.5
Total expected restructuring charges	12.7
Cumulative restructuring charges incurred to date	9.8
Remaining expected restructuring charges	2.9
Sparks Facility
Restructuring Reserve
Balance, Beginning of Period	3.2
Restructuring Charges (Adjustments)	0.6
Cash payments	(0.5)
Non-cash charges	0.0
Balance, End of Period	3.3
Total expected restructuring charges	6.2
Cumulative restructuring charges incurred to date	5.3
Remaining expected restructuring charges	0.9
Cobourg Facility
Restructuring Reserve
Balance, Beginning of Period	4.2
Restructuring Charges (Adjustments)	0.3
Cash payments	(0.3)
Non-cash charges	0.0
Balance, End of Period	4.2
Total expected restructuring charges	6.5
Cumulative restructuring charges incurred to date	4.5
Remaining expected restructuring charges	$ 2.0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of costs incurred to date for the specified restructuring cost.

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Amount expected to be recognized in earnings for the specified restructuring cost.

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Amount of expected cost remaining for the specified restructuring cost.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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