Commitments and Contingencies (Details)	12 Months Ended
	Sep. 30, 2025 USD ($) subsidiary	Sep. 30, 2024 USD ($)	Dec. 31, 2017 USD ($) record_of_decision	Mar. 24, 2023 person
Loss Contingencies
Environmental expenditures cap during calendar year	$ 5,000,000
West Reading, Pennsylvania Explosion
Loss Contingencies
Number of fatalities | person				7
Number of injuries | person				10
MGP sites in Pennsylvania
Loss Contingencies
Accrual for environmental loss contingencies	$ 63,000,000	$ 54,000,000
UGI Utilities, Inc.
Loss Contingencies
Number of subsidiaries acquired with similar histories | subsidiary	2
AmeriGas OLP | Saranac Lake, New York | NYDEC ROD
Loss Contingencies
Loss contingency, number of remediation plans | record_of_decision			3
Estimated remediation plan cost			$ 28,000,000
AmeriGas OLP | Saranac Lake, New York | New York State Department of Environment Conservation Remediation Plan
Loss Contingencies
Remediation expense		$ 19,000,000