Adjustments for gain (loss) on disposals investments in subsidiaries, joint ventures and associates to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Associates [member]; Joint ventures [member]; Subsidiaries [member]; Investments in subsidiaries, joint ventures and associates reported in separate financial statements; Profit (loss)]

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The discount rate used in the current estimate of the present value of the future cash flows expected to be derived from an asset or cash-generating unit.

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The amount of impairment loss on financial assets. [Refer: Financial assets; Impairment loss]

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The proportion of ownership interest in a joint venture attributable to the entity. [Refer: Joint ventures [member]]

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The amount of reclassification adjustments related to exchange differences when the financial statements of foreign operations are translated, before tax. Reclassification adjustments are amounts reclassified to profit (loss) in the current period that were recognised in other comprehensive income in the current or previous periods. [Refer: Other comprehensive income]

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SCOPE OF CONSOLIDATION - Associates Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of associates [line items]
Impairment charges		$ 0	$ 211	$ 0
Net gain (loss) on disposal of subsidiaries		104	1,460	101
Accumulated foreign exchange translation gains (losses) recognized in earnings due to decrease in ownership interest in investment		(105)	0	$ 105
DHS Group
Disclosure of associates [line items]
Impairment charges	$ 211	$ 211	$ 211
Discount rate used in current estimate of value in use	7.24%		7.24%
Baffinland
Disclosure of associates [line items]
Proportion of ownership interest in joint venture (in percent)			25.23%	25.70%	28.76%
Net gain (loss) on disposal of subsidiaries				$ (4)
Accumulated foreign exchange translation gains (losses) recognized in earnings due to decrease in ownership interest in investment				$ (12)