Consolidated Comprehensive Income Statements (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net Income	$ 532.3	$ 457.1	$ 1,496.1	$ 1,436.4
Other Comprehensive Income (Loss), net of tax
Translation adjustments, net of tax	128.7	106.9	399.8	(27.3)
Net gain (loss) on derivatives, net of tax	8.5	23.4	17.1	18.1
Reclassification adjustments:
Derivatives, net of tax	(12.0)	(23.2)	22.7	(43.8)
Pension and postretirement benefits, net of tax	18.7	19.8	55.3	60.7
Total Other Comprehensive Income	143.9	126.9	494.9	7.7
Comprehensive Income	676.2	584.0	1,991.0	1,444.1
Net Income (Loss) Attributable to Noncontrolling Interests	(1.3)	10.6	7.4	36.5
Other Comprehensive Income Attributable to Noncontrolling Interests	1.4	1.8	36.7	(14.8)
Comprehensive Income Attributable to Air Products	$ 676.1	$ 571.6	$ 1,946.9	$ 1,422.4