Summary of Significant Accounting Policies (Policies)	9 Months Ended
Jun. 30, 2021
Accounting Policies [Abstract]
Restricted Cash	Restricted Cash. Restricted cash principally represents those cash balances in our commodity futures brokerage accounts that are restricted from withdrawal.
Earnings Per Common Share	Earnings Per Common Share. Basic earnings per share attributable to UGI stockholders reflect the weighted-average number of common shares outstanding. Diluted earnings per share attributable to UGI stockholders include the effects of dilutive stock options and common stock awards.
Derivative Instruments	Derivative Instruments. Derivative instruments are reported on the Condensed Consolidated Balance Sheets at their fair values, unless the NPNS exception is elected. The accounting for changes in fair value depends upon the purpose of the derivative instrument, whether it is subject to regulatory ratemaking mechanisms or if it qualifies and is designated as a hedge for accounting purposes. Certain of our derivative instruments qualify and are designated as cash flow hedges. For cash flow hedges, changes in the fair values of the derivative instruments are recorded in AOCI, to the extent effective at offsetting changes in the hedged item, until earnings are affected by the hedged item. We discontinue cash flow hedge accounting if occurrence of the forecasted transaction is determined to be no longer probable. Hedge accounting is also discontinued for derivatives that cease to be highly effective. We do not designate our commodity and certain foreign currency derivative instruments as hedges under GAAP. Changes in the fair values of these derivative instruments are reflected in net income. Gains and losses on substantially all of the commodity derivative instruments used by UGI Utilities are included in regulatory assets or liabilities because it is probable such gains or losses will be recoverable from, or refundable to, customers. From time to time, we also enter into net investment hedges. Gains and losses on net investment hedges that relate to our foreign operations are included in the cumulative translation adjustment component in AOCI until such foreign net investment is substantially sold or liquidated. Cash flows from derivative instruments, other than certain cross-currency swaps and net investment hedges, if any, are included in cash flows from operating activities on the Condensed Consolidated Statements of Cash Flows. Cash flows from the interest portion of our cross-currency hedges, if any, are included in cash flows from operating activities while cash flows from the currency portion of such hedges, if any, are included in cash flows from financing activities. Cash flows from net investment hedges, if any, are included in cash flows from investing activities on the Condensed Consolidated Statements of Cash Flows.
Use of Estimates	Use of Estimates. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and costs. These estimates are based on management’s knowledge of current events, historical experience and various other assumptions that are believed to be reasonable under the circumstances. Accordingly, actual results may be different from these estimates and assumptions.
Reclassifications	Reclassifications. Certain prior-period amounts have been reclassified to conform to the current-period presentation.
New Accounting Standards Adopted in Fiscal 2021 And Accounting Standard Not Yet Adopted	New Accounting Standard Adopted in Fiscal 2021 Credit Losses. Effective October 1, 2020, the Company adopted ASU 2016-13, “Measurement of Credit Losses on Financial Instruments,” including subsequent amendments, using a modified retrospective transition approach. This ASU, as subsequently amended, requires entities to estimate lifetime expected credit losses for financial instruments not measured at fair value through net income, including trade and other receivables, net investments in leases, financial receivables, debt securities, and other financial instruments, which may result in earlier recognition of credit losses. Further, the new current expected credit loss model may affect how entities estimate their allowance for losses related to receivables that are current with respect to their payment terms. The adoption of the new guidance did not have a material impact on our consolidated financial statements. Accounting Standard Not Yet Adopted Income Taxes. In December 2019, the FASB issued ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes.” This ASU simplifies the accounting for income taxes by eliminating certain exceptions within the existing guidance for recognizing deferred taxes for equity method investments, performing intraperiod allocations and calculating income taxes in interim periods. Further, this ASU clarifies existing guidance related to, among other things, recognizing deferred taxes for goodwill and allocated taxes to members of a consolidated group. This new guidance is effective for the Company for interim and annual periods beginning October 1, 2021 (Fiscal 2022). Early adoption is permitted; however, the Company will adopt the new guidance effective October 1, 2021. The Company is in the process of assessing the impact on its financial statements from the adoption of the new guidance. Debt and Derivatives and Hedging. In August 2020, the FASB issued ASU 2020-06, “Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40).” The amendments in this ASU affect entities that issue convertible instruments and/or contracts indexed to and potentially settled in an entity’s own equity. This ASU reduces the number of accounting models for convertible debt instruments and convertible preferred stock, expands disclosure requirements for convertible instruments, and simplifies the related earnings per share guidance. This new guidance is effective for the Company for interim and annual periods beginning October 1, 2022 (Fiscal 2023). Early adoption is permitted. The amendments in this ASU may be adopted using the modified or full retrospective transition methods. The Company is in the process of assessing the impact on its financial statements from the adoption of the new guidance and determining the transition method and the period in which the new guidance will be adopted.
Equity Method Investments	We account for privately held equity securities of entities without readily determinable fair values in which we do not have control, but have significant influence over operating and financial policies, under the equity method. Our equity method investments are primarily comprised of PennEast, Pennant and Pine Run.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Jun. 30, 2021

Restricted Cash. Restricted cash principally represents those cash balances in our commodity futures brokerage accounts that are restricted from withdrawal.

Earnings Per Common Share

Earnings Per Common Share. Basic earnings per share attributable to UGI stockholders reflect the weighted-average number of common shares outstanding. Diluted earnings per share attributable to UGI stockholders include the effects of dilutive stock options and common stock awards.

Derivative Instruments

Derivative Instruments. Derivative instruments are reported on the Condensed Consolidated Balance Sheets at their fair values, unless the NPNS exception is elected. The accounting for changes in fair value depends upon the purpose of the derivative instrument, whether it is subject to regulatory ratemaking mechanisms or if it qualifies and is designated as a hedge for accounting purposes.

Certain of our derivative instruments qualify and are designated as cash flow hedges. For cash flow hedges, changes in the fair values of the derivative instruments are recorded in AOCI, to the extent effective at offsetting changes in the hedged item, until earnings are affected by the hedged item. We discontinue cash flow hedge accounting if occurrence of the forecasted

transaction is determined to be no longer probable. Hedge accounting is also discontinued for derivatives that cease to be highly effective. We do not designate our commodity and certain foreign currency derivative instruments as hedges under GAAP. Changes in the fair values of these derivative instruments are reflected in net income. Gains and losses on substantially all of the commodity derivative instruments used by UGI Utilities are included in regulatory assets or liabilities because it is probable such gains or losses will be recoverable from, or refundable to, customers. From time to time, we also enter into net investment hedges. Gains and losses on net investment hedges that relate to our foreign operations are included in the cumulative translation adjustment component in AOCI until such foreign net investment is substantially sold or liquidated.

Cash flows from derivative instruments, other than certain cross-currency swaps and net investment hedges, if any, are included in cash flows from operating activities on the Condensed Consolidated Statements of Cash Flows. Cash flows from the interest portion of our cross-currency hedges, if any, are included in cash flows from operating activities while cash flows from the currency portion of such hedges, if any, are included in cash flows from financing activities. Cash flows from net investment hedges, if any, are included in cash flows from investing activities on the Condensed Consolidated Statements of Cash Flows.

Use of Estimates

Use of Estimates. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and costs. These estimates are based on management’s knowledge of current events, historical experience and various other assumptions that are believed to be reasonable under the circumstances. Accordingly, actual results may be different from these estimates and assumptions.

Reclassifications

Reclassifications. Certain prior-period amounts have been reclassified to conform to the current-period presentation.

New Accounting Standards Adopted in Fiscal 2021 And Accounting Standard Not Yet Adopted

New Accounting Standard Adopted in Fiscal 2021

Credit Losses. Effective October 1, 2020, the Company adopted ASU 2016-13, “Measurement of Credit Losses on Financial Instruments,” including subsequent amendments, using a modified retrospective transition approach. This ASU, as subsequently amended, requires entities to estimate lifetime expected credit losses for financial instruments not measured at fair value through net income, including trade and other receivables, net investments in leases, financial receivables, debt securities, and other financial instruments, which may result in earlier recognition of credit losses. Further, the new current expected credit loss model may affect how entities estimate their allowance for losses related to receivables that are current with respect to their payment terms. The adoption of the new guidance did not have a material impact on our consolidated financial statements.

Accounting Standard Not Yet Adopted

Income Taxes. In December 2019, the FASB issued ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes.” This ASU simplifies the accounting for income taxes by eliminating certain exceptions within the existing guidance for recognizing deferred taxes for equity method investments, performing intraperiod allocations and calculating income taxes in interim periods. Further, this ASU clarifies existing guidance related to, among other things, recognizing deferred taxes for goodwill and allocated taxes to members of a consolidated group. This new guidance is effective for the Company for interim and annual periods beginning October 1, 2021 (Fiscal 2022). Early adoption is permitted; however, the Company will adopt the new guidance effective October 1, 2021. The Company is in the process of assessing the impact on its financial statements from the adoption of the new guidance.

Debt and Derivatives and Hedging. In August 2020, the FASB issued ASU 2020-06, “Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40).” The amendments in this ASU affect entities that issue convertible instruments and/or contracts indexed to and potentially settled in an entity’s own equity. This ASU reduces the number of accounting models for convertible debt instruments and convertible preferred stock, expands disclosure requirements for convertible instruments, and simplifies the related earnings per share guidance. This new guidance is effective for the Company for interim and annual periods beginning October 1, 2022 (Fiscal 2023). Early adoption is permitted. The amendments in this ASU may be adopted using the modified or full retrospective transition methods. The Company is in the process of assessing the impact on its financial statements from the adoption of the new guidance and determining the transition method and the period in which the new guidance will be adopted.

Equity Method Investments

We account for privately held equity securities of entities without readily determinable fair values in which we do not have control, but have significant influence over operating and financial policies, under the equity method. Our equity method investments are primarily comprised of PennEast, Pennant and Pine Run.