XML 47 R39.htm IDEA: XBRL DOCUMENT
v3.25.2

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) | 1 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jul. 31, 2025 | Mar. 31, 2025 | Mar. 31, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Sep. 30, 2026 | Sep. 30, 2024 | Sep. 30, 2023
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Cash, cash equivalents, and restricted cash |  |  |  | $ 28,332,000 | $ 45,951,000 |  | $ 117,585,000 | $ 45,441,000
Cash and cash equivalents |  |  |  | 28,082,000 |  |  | 117,335,000 |
Restricted cash |  |  |  | 250,000 |  |  | 250,000 |
Assets held-for-sale |  |  |  | 1,000,000 |  |  |  |
Derivative maximum payout |  |  |  | 5,000,000 | 0 |  |  |
Accrued expenses and other current liabilities |  |  |  | 133,163,000 |  |  | 116,317,000 |
Other long-term liabilities |  |  |  | 16,244,000 |  |  | 16,273,000 |
Subsequent Event |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Assets held-for-sale | $ 1,000,000 |  |  |  |  |  |  |
Cash proceeds from sale of assets | $ 4,900,000 |  |  |  |  |  |  |
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 |  |  |  | 15,400,000 |  |  | 15,700,000 |
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 |  |  |  | $ 18,300,000 |  |  | $ 19,300,000 |
Financial Products Corporation |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Delivery and branch expense reduced under weather hedge contract |  | $ 3,100,000 | $ 7,500,000 |  |  |  |  |
Scenario Forecast |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Derivative maximum receivable |  |  |  |  |  | $ 15,000,000 |  |
Derivative maximum payout |  |  |  |  |  | $ 5,000,000 |  |
Maximum |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Cash equivalents, highly liquid investments maturity |  |  |  | 3 months |  |  |  |
Derivative maximum receivable |  |  |  | $ 15,000,000 | $ 12,500,000 |  |  |

X
- Definition Cash equivalents, maturity period. + References No definition available. + Details
Name: | sgu_CashEquivalentsMaturityPeriod
Namespace Prefix: | sgu_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Derivative maximum payout under weather hedge contract. + References No definition available. + Details
Name: | sgu_DerivativeMaximumPayoutUnderWeatherHedgeContract
Namespace Prefix: | sgu_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Right to receive payment under weather hedge contract. + References No definition available. + Details
Name: | sgu_RightToReceivePaymentUnderWeatherHedgeContract
Namespace Prefix: | sgu_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Schedule Of Significant Accounting Policies [Line Items] + References No definition available. + Details
Name: | sgu_ScheduleOfSignificantAccountingPoliciesLineItems
Namespace Prefix: | sgu_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(20)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_AccruedLiabilitiesCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of assets held-for-sale that are not part of a disposal group. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 15 -Paragraph 4 -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482309/360-10-15-4 + Details
Name: | us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483467/210-10-45-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-4 + Details
Name: | us-gaap_CashAndCashEquivalentsAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including, but not limited to, disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-8 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 24 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-24 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-4 + Details
Name: | us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A + Details
Name: | us-gaap_DerivativeGainLossOnDerivativeNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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. + Details
Name: | us-gaap_MultiemployerPlansWithdrawalObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_OtherLiabilitiesNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 12 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-12 + Details
Name: | us-gaap_ProceedsFromSaleOfPropertyHeldForSale
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-8 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-4 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 45 -Paragraph 5 -SubTopic 210 -Topic 954 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477220/954-210-45-5 + Details
Name: | us-gaap_RestrictedCashAndCashEquivalentsNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=sgu_FinancialProductsCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |