Consolidated Statements Of Equity (USD $) In Millions	Common Stock [Member]		Capital In Excess Of Par [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]	Air Product Shareholders' Equity [Member]	Non-Controlling Interests [Member]	Total
Balance at Sep. 30, 2008 (Scenario, Previously Reported [Member])	$ 249.4	[1]	$ 811.7	$ 6,990.2	$ (549.3)	$ (2,471.3)	$ 5,030.7	$ 136.2	$ 5,166.9
Balance (Restatement Adjustment [Member])				(8.1)	35.8		27.7		27.7
Balance at Sep. 30, 2008	249.4	[1]	811.7	6,982.1	(513.5)	(2,471.3)	5,058.4	136.2	5,194.6
Comprehensive Income
Net Income				631.3			631.3	11.4	642.7
Translation adjustments, net of tax					(148.3)		(148.3)	(0.8)	(149.1)
Net gain (loss) on derivatives, net of tax					(4.5)		(4.5)	(0.2)	(4.7)
Unrealized holding gain (loss) on available-for-sale securities, net of tax					2.4		2.4		2.4
Pension and postretirement benefits, net of tax					(518.3)		(518.3)	(1.6)	(519.9)
Reclassification adjustments:
Currency translation adjustment					(3.2)		(3.2)		(3.2)
Derivatives, net of tax (benefit)					(0.7)		(0.7)		(0.7)
Pension and postretirement benefits, net of tax					24.3		24.3		24.3
Comprehensive Income							(17.0)	8.8	(8.2)
Share-based compensation expense			59.3				59.3		59.3
Issuance of treasury shares for stock option and award plans			(71.9)			118.1	46.2		46.2
Tax benefit of stock option and award plans			23.8				23.8		23.8
Cash dividends				(376.3)			(376.3)		(376.3)
Dividends to noncontrolling interests								(8.9)	(8.9)
Purchase of noncontrolling interests								(0.4)	(0.4)
Contribution from noncontrolling interests								2.4	2.4
Other				(2.5)			(2.5)		(2.5)
Balance at Sep. 30, 2009	249.4	[1]	822.9	7,234.6	(1,161.8)	(2,353.2)	4,791.9	138.1	4,930.0
Comprehensive Income
Net Income				1,029.1			1,029.1	25.4	1,054.5
Translation adjustments, net of tax					136.4		136.4	2.0	138.4
Net gain (loss) on derivatives, net of tax					(11.6)		(11.6)		(11.6)
Unrealized holding gain (loss) on available-for-sale securities, net of tax					20.2		20.2		20.2
Pension and postretirement benefits, net of tax					(201.7)		(201.7)	(0.2)	(201.9)
Reclassification adjustments:
Currency translation adjustment					(0.7)		(0.7)		(0.7)
Derivatives, net of tax (benefit)					14.8		14.8		14.8
Available-for-sale securities, net of tax (benefit)					(10.0)		(10.0)		(10.0)
Pension and postretirement benefits, net of tax					55.0		55.0		55.0
Comprehensive Income							1,031.5	27.2	1,058.7
Share-based compensation expense			48.6				48.6		48.6
Issuance of treasury shares for stock option and award plans			(76.0)			155.7	79.7		79.7
Tax benefit of stock option and award plans			35.0				35.0		35.0
Cash dividends				(408.4)			(408.4)		(408.4)
Dividends to noncontrolling interests								(18.7)	(18.7)
Purchase of noncontrolling interests			(28.3)				(28.3)	(10.8)	(39.1)
Contribution from noncontrolling interests								14.7	14.7
Other				(3.1)			(3.1)	0.2	(2.9)
Balance at Sep. 30, 2010	249.4	[1]	802.2	7,852.2	(1,159.4)	(2,197.5)	5,546.9	150.7	5,697.6
Comprehensive Income
Net Income				1,224.2			1,224.2	37.3	1,261.5
Translation adjustments, net of tax					(87.2)		(87.2)	4.4	(82.8)
Net gain (loss) on derivatives, net of tax					0.9		0.9	(0.1)	0.8
Unrealized holding gain (loss) on available-for-sale securities, net of tax					(4.6)		(4.6)		(4.6)
Pension and postretirement benefits, net of tax					(66.6)		(66.6)		(66.6)
Reclassification adjustments:
Currency translation adjustment					0.4		0.4		0.4
Derivatives, net of tax (benefit)					11.5		11.5		11.5
Available-for-sale securities, net of tax (benefit)					(16.1)		(16.1)		(16.1)
Pension and postretirement benefits, net of tax					67.7		67.7		67.7
Comprehensive Income							1,130.2	41.6	1,171.8
Share-based compensation expense			44.8				44.8		44.8
Purchase of treasury shares						(649.2)	(649.2)		(649.2)
Issuance of treasury shares for stock option and award plans			(98.6)			241.4	142.8		142.8
Tax benefit of stock option and award plans			63.7				63.7		63.7
Cash dividends				(473.8)			(473.8)		(473.8)
Dividends to noncontrolling interests								(31.4)	(31.4)
Purchase of noncontrolling interests			(6.1)				(6.1)		(6.1)
Contribution from noncontrolling interests								1.4	1.4
Other			(0.4)	(3.1)			(3.5)	(19.4)	(22.9)
Balance at Sep. 30, 2011	$ 249.4	[1]	$ 805.6	$ 8,599.5	$ (1,253.4)	$ (2,605.3)	$ 5,795.8	$ 142.9	$ 5,938.7

[1] Refer to Note 17, Capital stock, for a rollforward of shares