Condensed Financial Information of Registrant (Parent Company) (Details 2) (USD $) In Millions	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Condensed Financial Statements, Captions [Line Items]
NET CASH PROVIDED BY OPERATING ACTIVITIES (a)	$ 554.7	$ 598.8	$ 665.0
CASH FLOWS FROM INVESTING ACTIVITIES:
Net cash used by investing activities	(415.4)	(399.3)	(519.9)
CASH FLOWS FROM FINANCING ACTIVITIES:
Dividends on UGI Common Stock	(113.8)	(98.6)	(85.1)
Issuance of Common Stock	27.3	27.5	10.8
Net cash used by financing activities	(152.1)	(213.6)	(114.6)
Cash and cash equivalents decrease	(22.2)	(19.4)	34.9
Cash and cash equivalents:
End of year	238.5	260.7	280.1
Beginning of year	260.7	280.1	245.2
Decrease	(22.2)	(19.4)	34.9
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
NET CASH PROVIDED BY OPERATING ACTIVITIES (a)	201.6	173.0	124.7
CASH FLOWS FROM INVESTING ACTIVITIES:
Net investments in unconsolidated subsidiaries	(119.4)	(106.6)	(50.4)
Net cash used by investing activities	(119.4)	(106.6)	(50.4)
CASH FLOWS FROM FINANCING ACTIVITIES:
Dividends on UGI Common Stock	(113.8)	(98.6)	(85.1)
Issuance of Common Stock	31.0	31.8	10.8
Net cash used by financing activities	(82.8)	(66.8)	(74.3)
Cash and cash equivalents decrease	(0.6)	(0.4)
Cash and cash equivalents:
End of year	0.4	1.0	1.4
Beginning of year	1.0	1.4	1.4
Decrease	$ (0.6)	$ (0.4)

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).

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