Consolidated Comprehensive Income Statements (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Consolidated Comprehensive Income Statements [Abstract]
Net Income	$ 492.5	$ 335.0	$ 1,051.0	$ 922.4
Other Comprehensive Income (Loss), net of tax:
Translation adjustments, net of tax	(150.6)	103.0	(54.9)	267.4
Net gain (loss) on derivatives, net of tax	(3.7)	5.3	(14.1)	7.7
Unrealized holding gain (loss) on available-for-sale securities, net of tax	0	0	0	(4.6)
Pension and postretirement benefits, net of tax	0	0	0	0
Reclassification adjustments:
Currency translation adjustment	13.3	0	13.3	0
Derivatives, net of tax	(2.2)	(4.9)	9.8	0.5
Available-for-sale securities, net of tax	0	0	0	(16.1)
Pension and postretirement benefits, net of tax	16.1	16.8	48.2	50.4
Total Other Comprehensive Income (Loss)	(127.1)	120.2	2.3	305.3
Comprehensive Income	365.4	455.2	1,053.3	1,227.7
Comprehensive Income Attributable to Noncontrolling Interests	6.6	11.9	25.1	34.3
Comprehensive Income Attributable to Air Products	$ 358.8	$ 443.3	$ 1,028.2	$ 1,193.4