Leases - Schedule of Movement in Net Investment in Sublease ROU Asset (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Disclosure Of Movement In Net Investment In Sub Lease Of R O U Asset [Abstract]
Balance at the beginning	$ 53	$ 58	$ 62
Additions	1
Interest income accrued during the period	2	2	2
Lease receipts	(7)	(7)	(6)
Balance at the end	$ 49	$ 53	$ 58

The amount of income from subleasing right-of-use assets. Sublease is a transaction for which an underlying asset is re-leased by a lessee (‘intermediate lessor’) to a third party, and the lease (‘head lease’) between the head lessor and lessee remains in effect. [Refer: Right-of-use assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2021-01-01
-Paragraph 53
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2021-en-r&anchor=para_53_f&doctype=Standard
-URIDate 2021-03-24

Name:	ifrs-full_IncomeFromSubleasingRightofuseAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration