CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) $ in Millions	Dec. 25, 2020 USD ($) shares	Dec. 25, 2020 SFr / shares	Sep. 25, 2020 USD ($) shares	Sep. 25, 2020 SFr / shares
CONDENSED CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts (in dollars) \| $	$ 33		$ 29
Common shares, par value (in currency per share) \| SFr / shares		SFr 0.57		SFr 0.57
Common shares, shares authorized	338,953,381		338,953,381
Common shares, shares issued	338,953,381		338,953,381
Treasury shares	7,836,597		8,295,878

Amount of allowance for credit loss on accounts receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Section 45
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Face amount or stated value per share of common stock.

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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 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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