Consolidated Income Statements - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Sep. 30, 2019		Sep. 30, 2018		Sep. 30, 2017
Income Statement [Abstract]
Sales	$ 8,918.9		$ 8,930.2		$ 8,187.6
Cost of sales	5,975.5		6,189.5		5,751.5
Facility closure	29.0		0.0		0.0
Selling and administrative	750.0		760.8		713.5
Research and development	72.9		64.5		57.6
Business separation costs	0.0		0.0		32.5
Cost reduction and asset actions	25.5		0.0		151.4
Goodwill and intangible asset impairment charge	0.0		0.0		162.1
Gain on exchange of equity affiliate investments	29.1		0.0		0.0
Other income (expense), net	49.3		50.2		121.0
Operating Income	2,144.4		1,965.6		1,440.0
Equity affiliates' income	215.4		174.8		80.1
Interest expense	137.0		130.5		120.6
Other non-operating income (expense), net	66.7		5.1		16.6
Income From Continuing Operations Before Taxes	2,289.5		2,015.0		1,416.1
Income tax provision	480.1	[1]	524.3	[1],[2]	260.9
Income From Continuing Operations	1,809.4		1,490.7		1,155.2
Income from discontinued operations, net of tax	0.0		42.2		1,866.0
Net Income	1,809.4		1,532.9		3,021.2
Net income attributable to noncontrolling interests of continuing operations	49.4		35.1		20.8
Net Income Attributable to Air Products	1,760.0		1,497.8		3,000.4
Net Income Attributable to Air Products
Net income from continuing operations	1,760.0		1,455.6		1,134.4
Net income from discontinued operations	0.0		42.2		1,866.0
Net Income Attributable to Air Products	$ 1,760.0		$ 1,497.8		$ 3,000.4
Basic Earnings Per Common Share Attributable to Air Products
Basic earnings per share from continuing operations (in dollars per share)	$ 7.99		$ 6.64		$ 5.20
Basic earnings per share from discontinued operations (in dollars per share)	0		0.19		8.56
Basic Earnings Per Common Share Attributable to Air Products (in dollars per share)	7.99		6.83		13.76
Diluted Earnings Per Common Share Attributable to Air Products
Diluted earnings per share from continuing operations (in dollars per share)	7.94		6.59		5.16
Diluted earnings per share from discontinued operations (in dollars per share)	0		0.19		8.49
Diluted Earnings Per Common Share Attributable to Air Products (in dollars per share)	$ 7.94		$ 6.78		$ 13.65
Weighted Average Common Shares - Basic (in millions)	220.3		219.3		218.0
Weighted Average Common Shares - Diluted (in millions)	221.6		220.8		219.8

[1] Our income tax provision for fiscal years 2019 and 2018 reflects impacts from the U.S. Tax Cuts and Jobs Act (the "Tax Act"). Refer to Note 23, Income Taxes, for additional information. Fiscal year 2019 includes a discrete net income tax expense of $43.8, primarily recorded in the first quarter to finalize our estimates of the impacts of the Tax Act. Fiscal year 2018 includes a discrete net income tax expense of $180.6, primarily recorded in the first quarter for our initial estimates of the impacts of the Tax Act.

[2] Includes an income tax benefit of $35.7, net of reserves for uncertain tax positions, resulting from the restructuring of several foreign subsidiaries, primarily during the second quarter.