Consolidated Income Statements (Unaudited) - USD ($) shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Sales		$ 2,604.7	$ 2,065.2	$ 7,481.9	$ 6,536.2
Cost of sales		1,801.9	1,344.9	5,179.8	4,291.6
Facility closure		0.0	0.0	23.2	0.0
Selling and administrative		213.3	176.9	626.3	580.3
Research and development		23.2	19.9	67.8	56.8
Gain on exchange with joint venture partner		0.0	0.0	36.8	0.0
Company headquarters relocation income (expense)		0.0	0.0	0.0	33.8
Other income (expense), net		10.8	15.7	43.1	36.1
Operating Income		577.1	539.2	1,664.7	1,677.4
Equity affiliates' income		63.2	51.2	202.3	197.6
Interest expense		35.6	32.1	108.4	70.1
Other non-operating income (expense), net		21.1	8.1	56.5	24.3
Income From Continuing Operations Before Taxes		625.8	566.4	1,815.1	1,829.2
Income tax provision		101.7	109.3	337.5	378.5
Income From Continuing Operations		524.1	457.1	1,477.6	1,450.7
Income (Loss) from discontinued operations, net of tax		8.2	0.0	18.5	(14.3)
Net Income		532.3	457.1	1,496.1	1,436.4
Net income (loss) attributable to noncontrolling interests of continuing operations		(1.3)	10.6	7.4	36.5
Net Income Attributable to Air Products		533.6	446.5	1,488.7	1,399.9
Net Income Attributable to Air Products
Net income from continuing operations		525.4	446.5	1,470.2	1,414.2
Net income (loss) from discontinued operations		8.2	0.0	18.5	(14.3)
Net Income Attributable to Air Products		$ 533.6	$ 446.5	$ 1,488.7	$ 1,399.9
Per Share Data
Basic EPS from continuing operations (in dollars per share)	[1]	$ 2.37	$ 2.02	$ 6.63	$ 6.40
Basic EPS from discontinued operations (in dollars per share)	[1]	0.04	0	0.08	(0.06)
Basic EPS Attributable to Air Products (in dollars per share)	[1]	2.41	2.02	6.72	6.33
Diluted EPS from continuing operations (in dollars per share)	[1]	2.36	2.01	6.61	6.36
Diluted EPS from discontinued operations (in dollars per share)	[1]	0.04	0	0.08	(0.06)
Diluted EPS Attributable to Air Products (in dollars per share)	[1]	$ 2.40	$ 2.01	$ 6.69	$ 6.30
Weighted Average Common Shares (in millions)
Basic		221.6	221.2	221.6	221.1
Diluted		222.5	222.4	222.5	222.3

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