Accumulated Other Comprehensive Loss (Reclassification) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Other (income) expense, net	$ (20.4)		$ (11.6)
Interest expense	33.3		35.8
Net Income Attributable to Air Products	(290.2)		(278.3)
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | (Gain) Loss on Cash Flow Hedges [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Sales/cost of sales	0.2		0.7
Other (income) expense, net	(11.9)		(15.0)
Interest expense	(0.2)		0
Net Income Attributable to Air Products	(11.9)		(14.3)
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | Pension and postretirement benefits [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net Income Attributable to Air Products	$ 20.0	[1]	$ 24.4	[1]

[1] The components include prior service cost and actuarial loss amortization and are reflected in net periodic benefit cost. Refer to Note 9, Retirement Benefits.