Earnings Per Share (Schedule of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Numerator
Net income attributable to Air Products	$ 617.4	$ 609.3
Denominator (in millions)
Weighted average common shares — Basic (in shares)	222.7	222.5
Effect of dilutive securities
Employee stock option and other award plans (in shares)	0.2	0.3
Weighted average common shares — Diluted (in shares)	222.9	222.8
Per Share Data (U.S. Dollars per share)
Basic earnings per share attributable to Air Products (in dollars per share)	$ 2.77	$ 2.74
Diluted earnings per share attributable to Air Products (in dollars per share)	$ 2.77	$ 2.73