XML 68 R51.htm IDEA: XBRL DOCUMENT
v3.20.2

Revenue Recognition - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Sep. 30, 2020 | Sep. 30, 2019
Revenue Recognition [Line Items] |  |
Revenue, practical expedient, incremental cost of obtaining contract [true false] | true |
Contract costs, amortization period | 5 years |
Contract costs, impairment loss | $ 0 |
Contract liabilities | 139,600,000 | $ 127,000,000.0
Contract with customer liability, revenue recognized | 118,600,000 | 111,000,000.0
Prepaid Expense and Other Current Assets |  |
Revenue Recognition [Line Items] |  |
Deferred contract costs,current | 3,400,000 | 3,400,000
Deferred Charges and Other Assets, Net |  |
Revenue Recognition [Line Items] |  |
Deferred contract costs,non current | 5,900,000 | 5,900,000
Delivery and Branch Expenses |  |
Revenue Recognition [Line Items] |  |
Amortization of deferred contract costs | $ 4,000,000.0 | $ 4,000,000.0
Maximum |  |
Revenue Recognition [Line Items] |  |
Contract liabilities recognition service contract period | 1 year |
Equipment Maintenance Service Contracts | Maximum |  |
Revenue Recognition [Line Items] |  |
Revenue from service contracts period of recognition | 1 year |
Residential and Commercial Home Heating Oil Customers |  |
Revenue Recognition [Line Items] |  |
Percentage of customers receiving deliveries based on prevailing weather conditions | 95.00% |
Residential Customers |  |
Revenue Recognition [Line Items] |  |
Customer payment terms | 30 days |
Percentage of customers take advantage of smart pay budget payment plan | 34.00% |

X
- Definition Contract liabilities recognition service contract period. + References No definition available. + Details
Name: | sgu_ContractLiabilitiesRecognitionServiceContractPeriod
Namespace Prefix: | sgu_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Customer payment terms. + References No definition available. + Details
Name: | sgu_CustomerPaymentTerms
Namespace Prefix: | sgu_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of customers receiving deliveries based on prevailing weather conditions. + References No definition available. + Details
Name: | sgu_PercentageOfCustomersReceivingDeliveriesBasedOnPrevailingWeatherConditions
Namespace Prefix: | sgu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of customers take advantage of smart pay budget payment plan. + References No definition available. + Details
Name: | sgu_PercentageOfCustomersTakeAdvantageOfSmartPayBudgetPaymentPlan
Namespace Prefix: | sgu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue from service contracts period of recognition. + References No definition available. + Details
Name: | sgu_RevenueFromServiceContractsPeriodOfRecognition
Namespace Prefix: | sgu_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue recognition. + References No definition available. + Details
Name: | sgu_RevenueRecognitionLineItems
Namespace Prefix: | sgu_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
Name: | us-gaap_CapitalizedContractCostAmortization
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131251-203054 + Details
Name: | us-gaap_CapitalizedContractCostAmortizationPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
Name: | us-gaap_CapitalizedContractCostImpairmentLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
Name: | us-gaap_CapitalizedContractCostNetCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
Name: | us-gaap_CapitalizedContractCostNetNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130532-203044 + Details
Name: | us-gaap_ContractWithCustomerLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 + Details
Name: | us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Indicates (true false) whether practical expedient was elected to recognize incremental cost of obtaining contract as expense when incurred if amortization period would have been one year or less. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL51790836-203054 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130569-203045 + Details
Name: | us-gaap_RevenuePracticalExpedientIncrementalCostOfObtainingContract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:booleanItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_OtherNoncurrentAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=sgu_DeliveryAndBranchExpensesMember
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: |

X
- Details
Name: | srt_ProductOrServiceAxis=sgu_EquipmentMaintenanceServiceContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MajorCustomersAxis=sgu_ResidentialAndCommercialHomeHeatingOilCustomersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MajorCustomersAxis=sgu_ResidentialCustomersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |