Consolidated Statements of Financial Position (Parenthetical)	Sep. 30, 2022 $ / shares shares	Sep. 30, 2022 € / shares shares	Sep. 30, 2021 $ / shares shares	Sep. 30, 2021 € / shares shares
Ordinary shares, par value (in dollars per share) \| $ / shares	$ 0.01		$ 0.01
Ordinary shares authorized (in shares)	2,000,000,000	2,000,000,000	2,000,000,000	2,000,000,000
Ordinary shares issued (in shares)	717,726,243	717,726,243	737,090,363	737,090,363
Preferred shares authorized (in shares)	200,000,000	200,000,000	200,000,000	200,000,000
Preferred shares issued (in shares)	0	0	0	0
Preferred shares, par or stated value per share (in dollars per share) \| $ / shares	$ 0.01		$ 0.01
Ordinary shares held in treasury, at cost (in shares)	29,029,475	29,029,475	28,356,889	28,356,889
Common Class A
Ordinary shares, par value (in dollars per share) \| € / shares		€ 1.00		€ 1.00
Ordinary shares authorized (in shares)	40,000	40,000	40,000	40,000
Ordinary shares issued (in shares)	0	0	0	0

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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