Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Name:	us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Commitments and Contingencies (Details) $ in Thousands		9 Months Ended
Commitments and Contingencies (Details) $ in Thousands	Jul. 02, 2017 USD ($)	Jun. 30, 2019 USD ($) subsidiary	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)
Loss Contingencies [Line Items]
Public utilities, civil penalties	$ 2,100
PNG MGP \| Environmental Issue
Loss Contingencies [Line Items]
Environmental expenditures cap during year		$ 5,350
CPG, PNG and UGI Gas COAs
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies		$ 47,560	$ 50,970	$ 52,231
PNG and CPG
Loss Contingencies [Line Items]
Number of subsidiaries acquired with similar histories \| subsidiary		2