Associated companies (Details 2) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure of associates [line items]
Balance sheet value	$ 9,632	$ 8,644
Roche Holding AG, Switzerland
Disclosure of associates [line items]
Balance sheet value	9,407	8,445
Others
Disclosure of associates [line items]
Balance sheet value	$ 225	$ 199

The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2019-01-01
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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