Partnership Organization and Formation - Additional Information (Details) Customer in Millions	Sep. 29, 2018 Customer Location State shares	Sep. 30, 2017 shares
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Common units outstanding (in units)	61,405,409	61,105,000
Ownership interest in Suburban Energy Finance Corp (in hundredths)	100.00%
Number of residential, commercial, industrial and agricultural customers \| Customer	1.0
Number of locations served by the partnership \| Location	700
Number of states in which the partnership operates \| State	41
General Partner [Member] \| Common Unitholders [Member]
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Common units outstanding (in units)	784

This element represents the number of active residential, commercial, industrial and agricultural customers.

No definition available.

Name:	sph_NumberOfActiveResidentialCommercialIndustrialAndAgriculturalCustomers
Namespace Prefix:	sph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of locations served by the partnership as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	sph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's ownership interest of a subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	sph_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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
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Period Type:	duration

- Definition

The number of limited partner units outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

+ Details

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

- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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Balance Type:
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- Details

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