Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended
	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Schedule Of Significant Accounting Policies [Line Items]
Cash, cash equivalents, and restricted cash	$ 20,175,000		$ 22,841,000	$ 45,441,000	$ 14,870,000
Cash and cash equivalents	19,925,000			45,191,000
Restricted cash	250,000			250,000
Derivative maximum payout				5,000,000
Accrued expenses and other current liabilities	118,382,000			115,606,000
Other long-term liabilities	16,298,000			16,175,000
New England Teamsters & Trucking Industry Pension Fund
Schedule Of Significant Accounting Policies [Line Items]
Accrued expenses and other current liabilities	300,000			300,000
Other long-term liabilities	15,900,000			16,000,000.0
New England Teamsters & Trucking Industry Pension Fund | Significant Other Observable Inputs Level 2
Schedule Of Significant Accounting Policies [Line Items]
Multiemployer plan discounted withdrawal liability	19,600,000			$ 18,500,000
Financial Products Corporation
Schedule Of Significant Accounting Policies [Line Items]
Delivery and branch expense increased (reduced) under weather hedge contract	$ 1,000,000	$ 12,900,000	$ (400,000)
Maximum
Schedule Of Significant Accounting Policies [Line Items]
Cash equivalents, highly liquid investments maturity	3 months
Derivative maximum receivable	$ 12,500,000