Consolidated Balance Sheets (Parenthetical) shares in Millions, $ in Millions	Mar. 31, 2021 USD ($) shares	Mar. 31, 2021 SFr / shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2020 SFr / shares
Allowance for credit losses \| $	$ 119		$ 126
Common stock, par or stated value per share \| SFr / shares		SFr 0.10		SFr 0.10
Ordinary shares, authorized	2,495		2,495
Ordinary shares, issued	1,208		1,202
Treasury shares	106		106

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 210
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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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