Partnership Organization and Formation - Additional Information (Details) Customer in Millions	Sep. 26, 2020 Customer Location State shares	Sep. 28, 2019 shares
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Common units outstanding (in units)	62,146,403	61,735,000
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.

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- 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_
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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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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- 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=120397183&loc=d3e187171-122770

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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- Details

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