Cash equivalents, maturity period.

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- Definition

Derivative maximum payout under weather hedge contract.

+ References

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Right to receive payment under weather hedge contract.

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No definition available.

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- Definition

Schedule Of Significant Accounting Policies [Line Items]

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No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

+ References

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Amount of cash and cash equivalent, and cash and cash equivalent restricted to withdrawal or usage; including, but not limited to, discontinued operation. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

No definition available.

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- Definition

Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Amount of cash and cash equivalent restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	6 Months Ended		9 Months Ended	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Jun. 30, 2026	Sep. 30, 2027	Sep. 30, 2025	Jun. 30, 2025	Sep. 30, 2024
Schedule Of Significant Accounting Policies [Line Items]
Cash, cash equivalents, and restricted cash			$ 27,253,000		$ 24,933,000	$ 28,332,000	$ 117,585,000
Cash and cash equivalents			27,003,000		24,683,000
Restricted cash			250,000		250,000
Derivative maximum payout			5,000,000
Accrued expenses and other current liabilities			151,421,000		119,497,000
Other long-term liabilities			15,238,000		16,171,000
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			15,100,000		15,300,000
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			$ 17,600,000		$ 18,300,000
Financial Products Corporation
Schedule Of Significant Accounting Policies [Line Items]
Delivery and branch expense reduced under weather hedge contract	$ 5,000,000	$ 3,100,000
Scenario Forecast
Schedule Of Significant Accounting Policies [Line Items]
Derivative maximum receivable				$ 12,500,000
Maximum
Schedule Of Significant Accounting Policies [Line Items]
Cash equivalents, highly liquid investments maturity			3 months
Derivative maximum receivable			$ 15,000,000