Earnings per Share (Schedule of Earnings per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share
Income from continuing operations	$ 379.8	$ 291.9	$ 757.6	$ 618.2
Income (loss) from discontinued operations	(853.1)	(1.9)	(867.3)	(3.6)
Net Income (Loss) Attributable to Air Products	$ (473.3)	$ 290.0	$ (109.7)	$ 614.6
Weighted average number of common shares - Basic	216.1	214.9	215.9	214.5
Employee stock option and other award plans	1.8	2.5	1.9	2.5
Weighted average number of common shares - Diluted	217.9	217.4	217.8	217.0
Income from Continuing Operations, Basic	$ 1.76	$ 1.36	$ 3.51	$ 2.89
Income (loss) from Discontinued Operations, Basic	(3.95)	(0.01)	(4.02)	(0.02)
Net Income (Loss) Attributable to Air Products	(2.19)	1.35	(0.51)	2.87
Income from Continuing Operations, Diluted	1.74	1.34	3.47	2.85
Income (Loss) from Discontinued Operations, Diluted	(3.91)	(0.01)	(3.98)	(0.02)
Net Income (Loss) Attributable to Air Products	$ (2.17)	$ 1.33	$ (0.51)	$ 2.83