Earnings per Share (Schedule of Earnings per Share) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share
Income from continuing operations	$ 324.6	$ 287.1
Income from discontinued operations	0	3.1
Net Income Attributable to Air Products	$ 324.6us-gaap_NetIncomeLoss	$ 290.2us-gaap_NetIncomeLoss
Weighted average number of common shares outstanding	214.2	211.8
Employee stock option and other award plans	2.4	2.5
Weighted average number of common shares outstanding assuming dilution	216.6	214.3
Income from Continuing Operations, Basic	$ 1.52	$ 1.36
Income (loss) from Discontinued Operations, Basic	$ 0	$ 0.01
Net Income Attributable to Air Products	$ 1.52us-gaap_EarningsPerShareBasic	$ 1.37us-gaap_EarningsPerShareBasic
Income from Continuing Operations, Diluted	$ 1.5	$ 1.34
Income from Discontinued Operations, Diluted	$ 0	$ 0.01
Net Income Attributable to Air Products	$ 1.5us-gaap_EarningsPerShareDiluted	$ 1.35us-gaap_EarningsPerShareDiluted

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