Financial Instruments - Summary of Movement In Credit Allowance On Customer Balance (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Disclosure Of Financial Instruments [Line Items]
Balance at the beginning	$ 10,200
Impairment loss recognized / (reversed), net	13	$ 11	$ 28
Balance at the end	11,322	10,200
Accumulated Impairment \| Customer Balance
Disclosure Of Financial Instruments [Line Items]
Balance at the beginning	114	117	113
Translation differences	(2)	(2)	(3)
Impairment loss recognized / (reversed), net	13	11	28
Amounts written off	(11)	(12)	(21)
Balance at the end	$ 114	$ 114	$ 117

- Definition

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: Classes of financial instruments [domain]; Financial liabilities]

+ References + Details