Change in Income Tax Rate, Effect of Change on Earnings Per Share, Basic and Diluted

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Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount

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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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No definition available.

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For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, netted by jurisdiction.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
	Dec. 31, 2016	Mar. 31, 2017	Mar. 31, 2017	Sep. 30, 2016	Mar. 31, 2016	Sep. 30, 2015
Accounting Policies [Abstract]
Net deferred debt issuance costs					$ 29.6
Segment Reporting Information
Income tax benefits associated with share-based payments		$ 4.8	$ 7.0
Retained Earnings
Segment Reporting Information
Cumulative effect of change in accounting for employee share-based payments				$ 5.0		$ 0.0
New Accounting Pronouncement, Early Adoption, Effect \| Accounting Standards Update 2016-09
Segment Reporting Information
Decrease in deferred income tax liabilities for excess tax benefits related to prior periods				5.0
New Accounting Pronouncement, Early Adoption, Effect \| Accounting Standards Update 2016-09 \| Retained Earnings
Segment Reporting Information
Cumulative effect of change in accounting for employee share-based payments				$ 5.0
UGI France
Segment Reporting Information
Estimated deferred tax benefit resulting from future income tax reduction	$ 27.4
Reduction in per share, basic and diluted resulting from future income tax reduction (in dollars per share)	$ 0.15
Private Equity Partnership That Invests in Renewable Energy Companies
Segment Reporting Information
Carrying amount of investment		$ 11.0	$ 11.0