Availability required to pay distributions or repurchase common units.

No definition available.

Name:	sgu_AvailabilityRequiredToPayDistributionsOrRepurchaseCommonUnits
Namespace Prefix:	sgu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Minimum Fixed Charge Coverage Ratio For Distributions To Unitholders Or Repurchase Common Units

+ References

No definition available.

+ Details

Name:	sgu_MinimumFixedChargeCoverageRatioForDistributionsToUnitholdersOrRepurchaseCommonUnits
Namespace Prefix:	sgu_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of borrowing capacity to pay any distributions to unitholders or repurchase common units.

+ References

No definition available.

+ Details

Name:	sgu_MinimumPercentageOfBorrowingCapacityToPayAnyDistributionsToUnitholdersOrRepurchaseCommonUnits
Namespace Prefix:	sgu_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareRepurchaseProgramAxis=sgu_CommonStockRepurchaseProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareRepurchaseProgramAxis=sgu_StockRepurchaseProgramAdditionalAuthorizationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Common Unit Repurchase and Retirement - Additional Information (Detail) - USD ($) shares in Thousands	Jul. 30, 2015	Jun. 30, 2017	Jul. 31, 2013	Jul. 31, 2012
Capital Unit [Line Items]
Partnership's common units authorized for repurchase		7,344
Third Amendment
Capital Unit [Line Items]
Availability required to repurchase common units	$ 45,000,000
Percentage of the maximum facility size on a historical proforma and forward-looking basis	15.00%
Non Seasonal maximum borrowing capacity under revolving credit facility	$ 300,000,000
Minimum fixed charge coverage ratio for distributions to unit holders or to repurchase common units	115.00%
Initial Common Units Authorized Plan III Common Units Repurchase Program
Capital Unit [Line Items]
Partnership's common units authorized for repurchase				3,000
Additional Common Units Authorized Plan III Common Units Repurchase Program
Capital Unit [Line Items]
Partnership's common units authorized for repurchase			1,900