Accumulated Other Comprehensive Loss (Reclassification) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales	$ (3,102.5)	$ (2,931.5)
Cost of sales	2,107.5	2,016.5
Other income/expense, net	(10.6)	(22.9)
Interest expense	54.5	42.6
Other non-operating income (expense), net	1.4	(38.9)
Net Income attributable to Air Products	(678.2)	(617.4)
Reclassification out of Accumulated Other Comprehensive Income | Loss (Gain) on Cash Flow Hedges, net of tax
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales	(0.9)	0.2
Cost of sales	0.2	0.8
Interest expense	(0.3)	0.3
Other non-operating income (expense), net	17.6	90.6
Net Income attributable to Air Products	16.6	91.9
Reclassification out of Accumulated Other Comprehensive Income | Pension and Postretirement Benefits, net of tax
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net Income attributable to Air Products	$ 9.3	$ 11.0