XML 68 R54.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Inventories - Additional Information (Detail) - gal gal in Millions | 12 Months Ended
--- | ---
Sep. 30, 2017 | Sep. 30, 2016
Inventory [Line Items] |  |
Heating oil and other fuel inventories | 24.2 | 18.4
Maximum product supply by other supplier | 8.00% | 8.00%
Global Companies LLC |  |
Inventory [Line Items] |  |
Product purchases | 13.00% | 13.00%
Nic Holding Corp |  |
Inventory [Line Items] |  |
Product purchases | 8.00% | 8.00%
Home heating oil and Propane |  |
Inventory [Line Items] |  |
Market price based product supply contracts for next twelve months | 292.3 |
Diesel and gasoline |  |
Inventory [Line Items] |  |
Market price based product supply contracts for next twelve months | 47.0 |

X
- Definition Heating Oil And Other Fuel Inventories + References No definition available. + Details
Name: | sgu_HeatingOilAndOtherFuelInventories
Namespace Prefix: | sgu_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | instant

X
- Definition Market Price Based Product Supply Contracts + References No definition available. + Details
Name: | sgu_MarketPriceBasedProductSupplyContracts
Namespace Prefix: | sgu_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | instant

X
- Definition Maximum Percentage Of Product Purchases + References No definition available. + Details
Name: | sgu_MaximumPercentageOfProductPurchases
Namespace Prefix: | sgu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage Of Product Purchases + References No definition available. + Details
Name: | sgu_PercentageOfProductPurchases
Namespace Prefix: | sgu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_InventoryLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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

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

X
- Details
Name: | sgu_OilAndGasPropertyTypeAxis=sgu_HomeHeatingOilAndPropaneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | sgu_OilAndGasPropertyTypeAxis=sgu_DieselAndGasolineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |