Earnings Per Share (Schedule of Earnings per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Numerator
Net income (loss) from continuing operations		$ (386.5)	$ 3,842.1	$ 2,292.8
Net income (loss) from discontinued operations		(8.0)	(13.9)	7.4
Net Income (Loss) Attributable to Air Products		$ (394.5)	$ 3,828.2	$ 2,300.2
Denominator (in millions)
Weighted average common shares — Basic		222.7	222.5	222.3
Effect of dilutive securities
Employee stock option and other award plans		0.0	0.3	0.4
Weighted average common shares — Diluted		222.7	222.8	222.7
Per Share Data
Basic EPS from continuing operations (in dollars per share)	[1]	$ (1.74)	$ 17.27	$ 10.31
Basic EPS from discontinued operations (in dollars per share)	[1]	(0.04)	(0.06)	0.03
Basic Earnings (Loss) Per Share Attributable to Air Products (in dollars per share)	[1]	(1.77)	17.21	10.35
Diluted earnings (loss) per share from continuing operations (in dollars per share)	[1]	(1.74)	17.24	10.30
Diluted earnings (loss) per share from discontinued operations (in dollars per share)	[1]	(0.04)	(0.06)	0.03
Diluted Earnings (Loss) Per Share Attributable to Air Products (in dollars per share)	[1]	$ (1.77)	$ 17.18	$ 10.33

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