Commitments and Contingencies - UGI Standby Commitment to Purchase Class B Common Units (Details) - USD ($) $ in Millions		20 Months Ended
Nov. 07, 2017	Jul. 01, 2019
Subsequent Event \| Capital B Units
Other Commitments [Line Items]
Number of volume days of weighted average price of Partnership's common units	20 days
Basis points on annualized yield	1.30%
Period from initial issuance, holders may elect to convert units	5 years
Conversion ratio	1
Period from initial issuance, holders may elect to convert subject to certain conditions	6 years
Subsequent Event \| Capital B Units \| Minimum
Other Commitments [Line Items]
Trading price (as a percent)	110.00%
Forecast
Other Commitments [Line Items]
Amount of capital contribution		$ 225

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Name Accounting Standards Codification
-Topic 505
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-Paragraph 1
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