Equity method investment acquired, ownership percentage.

No definition available.

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Period Type:	instant

- Definition

Number of customers to provide service.

+ References

No definition available.

+ Details

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- Definition

Number of customers to whom home heating oil, gasoline and diesel fuel were sold on a delivery only basis.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of Full-service residential and commercial home heating oil and propane customers served.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgu_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

+ References

+ Details

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- Details

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Balance Type:	na
Period Type:	duration

- Definition

The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-04.16(a))

-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-Subparagraph (SAB TOPIC 4.F)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 16

-Subparagraph a, b

-Article 6

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-04.16(b))

-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

+ Details

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

- Definition

The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

+ References

No definition available.

+ Details

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Period Type:	duration

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- Details

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- Details

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- Details

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- Details

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- Details

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Partnership Organization - Additional Information (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	6 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Sep. 30, 2014
Limited Partners' Capital Account [Line Items]
Percentage of limited partner interest	99.43%
Percentage of general partner interest	0.57%
8.875% Senior Notes
Limited Partners' Capital Account [Line Items]
Outstanding senior notes	125
Interest on senior notes	8.875%	8.875%
Maturity of public notes due	Dec. 01, 2017
Star Acquisitions, Inc
Limited Partners' Capital Account [Line Items]
Ownership interest of partnership	100.00%
Petro Holdings, Inc
Limited Partners' Capital Account [Line Items]
Ownership interest of Star Acquisitions Inc.	100.00%
Number of full-service residential and commercial home heating oil and propane customers served	452,000
Number of customers to whom only home heating oil, gasoline and diesel fuel were sold on a delivery only basis	76,000
Number of customers to whom ancillary services were provided	24,000
Star Gas Finance Company
Limited Partners' Capital Account [Line Items]
Ownership interest of partnership	100.00%
Common Stock
Limited Partners' Capital Account [Line Items]
Number of outstanding units	57,282		57,405
General Partner
Limited Partners' Capital Account [Line Items]
Number of outstanding units	326		326