Significant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Income per limited partner unit
Common Unitholders' interest in net income attributable to AmeriGas Partners under the two-class method for MLPs (in dollars)	$ 86,241	$ 31,660
Weighted average Common units outstanding - basic (thousands)	92,820	57,133
Potentially dilutive Common Units (thousands)	82	60
Weighted average Common Units outstanding - diluted (thousands)	92,902	57,193

Common unit holders interest in net income attributable to AmeriGas partners under the two-class method for MLPs.

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- Details

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- Definition

Weighted average number of limited partnership units outstanding determined by relating the portion of time within a reporting period that general partnership units have been outstanding to the total time in that period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187171-122770

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

+ Details

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Weighted average number of limited partnership units outstanding determined by relating the portion of time within a reporting period that limited partnership units have been outstanding to the total time in that period. Used in the calculation of diluted net income or loss per limited partnership unit.

+ References

+ Details

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- Definition

The sum of dilutive potential limited partnership units used in the calculation of the diluted per-unit computation.

+ References

No definition available.

+ Details

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