Financial instruments and risk management - Summary of credit risk (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	$ 12,807	$ 10,381
Trade and other financial receivables	2,762	3,286
Investments in equity accounted units	3,504	3,764
Derivative assets	272	665
Loans to equity accounted units	0	41
Total	18,736	17,459
Credit risk
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	12,807	10,381
Trade and other financial receivables	2,762	3,286
Investments in equity accounted units	2,682	2,899
Derivative assets	272	665
Loans to equity accounted units	0	41
Total	$ 18,523	$ 17,272

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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