Consolidated Income Statements (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Sales	$ 2,224.0	$ 2,259.0	$ 6,635.7	$ 6,631.3
Cost of sales	1,466.0	1,545.4	4,484.7	4,623.7
Facility closure	0.0	0.0	29.0	0.0
Selling and administrative	188.5	188.6	568.1	574.8
Research and development	18.1	15.0	50.0	44.1
Cost reduction actions	25.5	0.0	25.5	0.0
Gain on exchange of equity affiliate investments	29.1	0.0	29.1	0.0
Other income (expense), net	14.7	5.8	33.7	43.2
Operating Income	569.7	515.8	1,541.2	1,431.9
Equity affiliates' income	56.4	58.1	155.5	115.6
Interest expense	34.2	34.9	106.9	95.1
Other non-operating income (expense), net	17.6	12.8	49.8	33.7
Income From Continuing Operations Before Taxes	609.5	551.8	1,639.6	1,486.1
Income tax provision	109.3	107.1	348.9	455.1
Income From Continuing Operations	500.2	444.7	1,290.7	1,031.0
Income From Discontinued Operations, net of tax	0.0	43.2	0.0	42.2
Net Income	500.2	487.9	1,290.7	1,073.2
Net Income Attributable to Noncontrolling Interests of Continuing Operations	12.2	14.0	33.9	28.3
Net Income Attributable to Air Products	488.0	473.9	1,256.8	1,044.9
Net Income Attributable to Air Products
Income from continuing operations	488.0	430.7	1,256.8	1,002.7
Income from discontinued operations	0.0	43.2	0.0	42.2
Net Income Attributable to Air Products	$ 488.0	$ 473.9	$ 1,256.8	$ 1,044.9
Basic Earnings Per Common Share Attributable to Air Products
Income from continuing operations, basic (in dollars per share)	$ 2.21	$ 1.96	$ 5.71	$ 4.57
Income from discontinued operations, basic (in dollars per share)	0	0.20	0	0.19
Net Income Attributable to Air Products (in dollars per share)	2.21	2.16	5.71	4.76
Diluted Earnings Per Common Share Attributable to Air Products
Income from continuing operations, diluted (in dollars per share)	2.20	1.95	5.68	4.54
Income from discontinued operations, diluted (in dollars per share)	0	0.20	0	0.19
Net Income Attributable to Air Products (in dollars per share)	$ 2.20	$ 2.15	$ 5.68	$ 4.73
Weighted Average Common Shares - Basic (in millions)	220.6	219.5	220.2	219.3
Weighted Average Common Shares - Diluted (in millions)	221.9	220.9	221.4	220.7