Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2022	Sep. 30, 2021
Air Products Shareholders’ Equity
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, issued shares	249,455,584	249,455,584
Treasury stock at cost, shares	27,656,602	28,058,829

Face amount or stated value per share of common stock.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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