Consolidated Statements of Equity - USD ($) $ in Millions	Total		Common Stock	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock, Common	Air Products Shareholders’ Equity	Non-controlling Interests
Beginning balance at Sep. 30, 2021	$ 14,088.0		$ 249.4	$ 1,115.8	$ 15,678.3	$ (1,515.9)	$ (1,987.9)	$ 13,539.7	$ 548.3
Stockholders' Equity [Roll Forward]
Net income	2,266.5		0.0	0.0	2,256.1	0.0	0.0	2,256.1	10.4
Other comprehensive income (loss)	(1,299.5)		0.0	0.0	0.0	(1,270.2)	0.0	(1,270.2)	(29.3)
Dividends on common stock	(1,410.6)		0.0	0.0	(1,410.6)	0.0	0.0	(1,410.6)	0.0
Distributions to noncontrolling interests	(4.8)		0.0	0.0	0.0	0.0	0.0	0.0	(4.8)
Share-based compensation	46.0		0.0	46.0	0.0	0.0	0.0	46.0	0.0
Issuance of treasury shares for stock option and award plans	(14.0)		0.0	(20.9)	0.0	0.0	6.9	(14.0)	0.0
Investments by noncontrolling interests	33.0		0.0	0.0	0.0	0.0	0.0	0.0	33.0
Purchase of noncontrolling interests	(1.9)		0.0	0.0	0.0	0.0	0.0	0.0	(1.9)
Other equity transactions	(0.3)		0.0	0.5	(3.5)	0.0	0.0	(3.0)	2.7
Ending balance at Sep. 30, 2022	$ 13,702.4		249.4	1,141.4	16,520.3	(2,786.1)	(1,981.0)	13,144.0	558.4
Stockholders' Equity [Roll Forward]
Dividends per share	$ 6.36
Net income	$ 2,338.6		0.0	0.0	2,300.2	0.0	0.0	2,300.2	38.4
Other comprehensive income (loss)	521.0		0.0	0.0	0.0	336.7	0.0	336.7	184.3
Dividends on common stock	(1,526.2)		0.0	0.0	(1,526.2)	0.0	0.0	(1,526.2)	0.0
Distributions to noncontrolling interests	(115.9)		0.0	0.0	0.0	0.0	0.0	0.0	(115.9)
Share-based compensation	54.6		0.0	54.6	0.0	0.0	0.0	54.6	0.0
Issuance of treasury shares for stock option and award plans	7.6		0.0	(6.1)	0.0	0.0	13.7	7.6	0.0
Investments by noncontrolling interests	682.2	[1]	0.0	0.0	0.0	0.0	0.0	0.0	682.2	[1]
Other equity transactions	(4.0)		0.0	0.6	(4.6)	0.0	0.0	(4.0)	0.0
Ending balance at Sep. 30, 2023	$ 15,660.3		249.4	1,190.5	17,289.7	(2,449.4)	(1,967.3)	14,312.9	1,347.4
Stockholders' Equity [Roll Forward]
Dividends per share	$ 6.87
Net income	$ 3,862.4		0.0	0.0	3,828.2	0.0	0.0	3,828.2	34.2
Other comprehensive income (loss)	274.7		0.0	0.0	0.0	421.7	0.0	421.7	(147.0)
Dividends on common stock	(1,569.7)		0.0	0.0	(1,569.7)	0.0	0.0	(1,569.7)	0.0
Distributions to noncontrolling interests	(25.4)		0.0	0.0	0.0	0.0	0.0	0.0	(25.4)
Share-based compensation	58.3		0.0	58.3	0.0	0.0	0.0	58.3	0.0
Issuance of treasury shares for stock option and award plans	(12.9)		0.0	3.9	0.0	0.0	(16.8)	(12.9)	0.0
Investments by noncontrolling interests	428.5		0.0	0.0	0.0	0.0	0.0	0.0	428.5
Other equity transactions	(2.5)		0.0	0.5	(2.5)	0.0	0.0	(2.0)	(0.5)
Ending balance at Sep. 30, 2024	$ 18,673.7		$ 249.4	$ 1,253.2	$ 19,545.7	$ (2,027.7)	$ (1,984.1)	$ 17,036.5	$ 1,637.2
Stockholders' Equity [Roll Forward]
Dividends per share	$ 7.06

[1] Includes noncash activity related to the NEOM Green Hydrogen Company joint venture. Refer to Note 3, Variable Interest Entities, for additional information.