CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS)/INCOME (unaudited) (parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019
Statement of comprehensive income [abstract]
Actuarial (losses)/gains from defined benefit plans, tax benefit	$ 5	$ 7	$ 2
Fair value adjustments on equity securities, tax benefit		$ 3	$ 5

The amount of income tax relating to amounts recognised in other comprehensive income in relation to investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: Other comprehensive income; Reserve of gains and losses from investments in equity instruments]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2019-01-01
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration