Related Party Transactions (Details) $ in Thousands	12 Months Ended
Sep. 30, 2016 USD ($) agreement Bcf	Sep. 30, 2015 USD ($) Bcf	Sep. 30, 2014 USD ($)
Related Party Transaction
Related party costs incurred	$ 11,863	$ 11,956	$ 10,671
UGI Energy Services, Inc
Related Party Transaction
Agreement term (in years)	1 year
Revenue from related parties	$ 30,743	79,182	109,913
Purchases from related party	$ 35,067	85,383	128,076
UGI Energy Services, Inc \| SCAAs
Related Party Transaction
Agreement term (in years)	3 years
Number of storage agreements \| agreement	1
Related party costs incurred	$ 12,739	16,849	38,299
UGI Energy Services, Inc \| Exclusive of Transactions Pursuant SCAAs
Related Party Transaction
Related party costs incurred	63,331	47,794	$ 35,810
UGI Energy Services, Inc \| Other Current Liabilities \| SCAAs
Related Party Transaction
Related party security deposits	$ 8,100	$ 10,700
UGI Energy Services, Inc \| Inventories
Related Party Transaction
Volume of gas storage inventory (in bcf of natural gas) \| Bcf	4.6	5.0
Natural gas storage inventory, related parties, current	$ 11,148	$ 12,889

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Number of Storage Contract Administrative Agreements

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Volume Of Gas Storage Inventory

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- Definition

Amount of deposits held by the entity for a related party (entity, shareholder, employee).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Related Parties
-URI http://asc.fasb.org/extlink&oid=16382449

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 225
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

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