Earnings Per Share (Schedule of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Earnings Per Share [Abstract]
Net income from continuing operations		$ 582.1	$ 525.4	$ 1,673.0	$ 1,470.2
Net income from discontinued operations		0.0	8.2	0.0	18.5
Net Income Attributable to Air Products		$ 582.1	$ 533.6	$ 1,673.0	$ 1,488.7
Weighted average common shares — Basic		222.0	221.6	222.0	221.6
Employee stock option and other award plans		0.5	0.9	0.5	0.9
Weighted average common shares — Diluted		222.5	222.5	222.5	222.5
Per Share Data
Basic EPS from continuing operations (in dollars per share)	[1]	$ 2.62	$ 2.37	$ 7.54	$ 6.63
Basic EPS from discontinued operations (in dollars per share)	[1]	0	0.04	0	0.08
Basic EPS Attributable to Air Products (in dollars per share)	[1]	2.62	2.41	7.54	6.72
Diluted EPS from continuing operations (in dollars per share)	[1]	2.62	2.36	7.52	6.61
Diluted EPS from discontinued operations (in dollars per share)	[1]	0	0.04	0	0.08
Diluted EPS Attributable to Air Products (in dollars per share)	[1]	$ 2.62	$ 2.40	$ 7.52	$ 6.69

[1] *Earnings per share ("EPS") is calculated independently for each component and may not sum to total EPS due to rounding.