Consolidated Income Statements (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Consolidated Income Statements [Abstract]
Sales	$ 2,344.3	$ 2,403.0	$ 4,665.8	$ 4,695.5
Cost of sales	1,715.8	1,748.2	3,438.1	3,417.8
Selling and administrative	237.3	242.0	468.4	468.5
Research and development	29.8	27.9	57.8	57.1
Cost reduction plan	86.8		86.8
Net loss on Airgas transaction		5.0		48.5
Other income, net	13.3	13.9	27.0	21.4
Operating Income	287.9	393.8	641.7	725.0
Equity affiliates' income	35.5	31.7	72.6	59.5
Interest expense	29.4	29.4	58.8	60.4
Income from Continuing Operations before Taxes	294.0	396.1	655.5	724.1
Income tax provision	8.8	103.2	136.2	176.5
Income from Continuing Operations	285.2	292.9	519.3	547.6
Income from Discontinued Operations, net of tax	17.0	18.6	39.2	39.8
Net Income	302.2	311.5	558.5	587.4
Less: Net Income Attributable to Noncontrolling Interests	6.2	7.2	14.4	14.5
Net income attributable to Air Products	296.0	304.3	544.1	572.9
Income from continuing operations	279.0	285.7	504.9	533.1
Income from discontinued operations	$ 17.0	$ 18.6	$ 39.2	$ 39.8
Income from continuing operations, Basic	$ 1.32	$ 1.34	$ 2.39	$ 2.49
Income from discontinued operations, Basic	$ 0.08	$ 0.08	$ 0.19	$ 0.19
Net Income Attributable to Air Products, Basic	$ 1.40	$ 1.42	$ 2.58	$ 2.68
Income from continuing operations, Diluted	$ 1.30	$ 1.31	$ 2.36	$ 2.44
Income from discontinued operations, Diluted	$ 0.08	$ 0.08	$ 0.18	$ 0.18
Net Income Attributable to Air Products, Diluted	$ 1.38	$ 1.39	$ 2.54	$ 2.62
Weighted Average of Common Shares Outstanding (in millions)	211.1	213.8	210.7	214.0
Weighted Average of Common Shares Outstanding Assuming Dilution (in millions)	215.0	218.8	214.5	219.0
Dividends Declared Per Common Share - Cash	$ 0.64	$ 0.58	$ 1.22	$ 1.07