Consolidated Income Statements - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Sales		$ 12,037.3	$ 12,100.6	$ 12,600.0
Cost of sales		8,256.0	8,168.7	8,833.0
Selling and administrative expense		906.1	942.4	957.0
Research and development expense		96.3	100.2	105.6
Business and asset actions		3,747.0	57.0	244.6
Shareholder activism-related costs		86.3	0.0	0.0
Gain on sale of business		67.3	1,575.6	0.0
Other income (expense), net		110.1	58.2	34.8
Operating Income (Loss)		(877.0)	4,466.1	2,494.6
Equity affiliates' income		647.7	647.7	604.3
Interest expense		214.0	218.8	177.5
Other non-operating income (expense), net		2.6	(73.8)	(39.0)
Income (Loss) From Continuing Operations Before Taxes		(440.7)	4,821.2	2,882.4
Income tax expense (benefit)		(94.3)	944.9	551.2
Income (Loss) From Continuing Operations		(346.4)	3,876.3	2,331.2
Income (Loss) from discontinued operations, net of tax		(8.0)	(13.9)	7.4
Net Income (Loss)		(354.4)	3,862.4	2,338.6
Net income attributable to noncontrolling interests		40.1	34.2	38.4
Net Income (Loss) Attributable to Air Products		(394.5)	3,828.2	2,300.2
Net Income (Loss) Attributable to Air Products
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
Per Share Data
Basic earnings (loss) per share from continuing operations (in dollars per share)	[1]	$ (1.74)	$ 17.27	$ 10.31
Basic earnings (loss) per share 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
Weighted Average Common Shares (in millions)
Basic (in shares)		222.7	222.5	222.3
Diluted (in shares)		222.7	222.8	222.7

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