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Income Taxes - Additional information (Details) - USD ($) $ in Millions			12 Months Ended
	Apr. 01, 2023	Mar. 31, 2023	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income taxes
Effective tax rate (as a percent)			24.70%	21.80%	19.70%
Valuation allowance related to net deferred tax assets			$ 154.4	$ 197.7
Corporate tax rate			21.00%	21.00%	21.00%
Tax expense related to audit settlement				$ 13.2
Tax rate changes			$ (4.1)	(26.8)	$ (0.5)
Tax benefit from foreign subsidiaries			(75.8)	(53.2)	(55.7)
United Kingdom
Income taxes
Effective tax rate (as a percent)	25.00%	19.00%
Tax rate changes				$ 25.9
CANADA
Income taxes
Valuation allowance related to net deferred tax assets					$ 31.7
Foreign
Income taxes
Valuation allowance related to net operating losses			$ 21.9

X

- Definition

Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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