Goodwill And Intangible Assets - Summary of Changes In Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Intangible Assets And Goodwill [Abstract]
Carrying value at the beginning	$ 563	$ 568
Goodwill on Brilliant Basics acquisition (Refer to note 2.9)	5
Goodwill reclassified under assets held for sale (Refer note no 2.9)	(247)
Translation differences	18	(5)
Carrying value at the end	$ 339	$ 563

The amount of additional goodwill recognised, except goodwill included in a disposal group that, on acquisition, meets the criteria to be classified as held for sale in accordance with IFRS 5. [Refer: Goodwill; Disposal groups classified as held for sale [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The decrease in goodwill due to classification as held for sale. [Refer: Goodwill; Disposal groups classified as held for sale [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The increase (decrease) in goodwill resulting from net exchange differences arising on the translation of the financial statements from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Goodwill]

+ References

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- References

No definition available.

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