Availability required to pay distributions or repurchase common units.

No definition available.

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

- Definition

Minimum fixed charge coverage ratio for distributions to unit holders or repurchase common units.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- 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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- 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

+ Details

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Data Type:	xbrli:monetaryItemType
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- 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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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

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Period Type:	duration

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- Details

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Common Unit Repurchase and Retirement - Additional Information (Detail) - USD ($) shares in Thousands		1 Months Ended			3 Months Ended		72 Months Ended	81 Months Ended
	Jul. 02, 2018	Mar. 31, 2019	Feb. 28, 2019	Jan. 31, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2019
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%
Repurchase Plan
Capital Unit [Line Items]
Company's common units repurchased and retired		197	1,474	516	2,187	599	7,937
Company's common units authorized for repurchase							10,900
Common Stock Available for Repurchase Under Open Market Transactions
Capital Unit [Line Items]
Company's common units authorized for repurchase							8,400
Common Stock Available for Repurchase Under Privately Negotiated Transactions
Capital Unit [Line Items]
Company's common units repurchased and retired								1,200
Company's common units authorized for repurchase							2,500
Common Stock Repurchase Under Open Market Transactions
Capital Unit [Line Items]
Company's common units repurchased and retired								7,100