Revenue Recognition - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Sep. 30, 2021
Revenue Recognition [Line Items]
Contract costs, amortization period	5 years
Contract liabilities	$ 105.0		$ 141.6
Contract with customer liability, revenue recognized	$ 123.8	$ 122.2
Maximum
Revenue Recognition [Line Items]
Contract liabilities recognition service contract period	1 year
Delivery and Branch Expenses
Revenue Recognition [Line Items]
Amortization of deferred contract costs	$ 3.0	$ 2.9
Prepaid Expense and Other Current Assets
Revenue Recognition [Line Items]
Deferred contract costs,current	3.4		3.4
Deferred Charges and Other Assets, Net
Revenue Recognition [Line Items]
Deferred contract costs,non current	$ 5.7		$ 5.7