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v3.19.1

Operating Segments - Additional Information (Detail) | 12 Months Ended
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Mar. 31, 2019 Customer Segment | Mar. 31, 2018 Customer | Mar. 31, 2017
Disclosure of operating segments [Line Items] |  |  |
Number of reportable segment | Segment | 2 |  |
WNS Global BPM segment [member] |  |  |
Disclosure of operating segments [Line Items] |  |  |
Number of clients individually accounted for more than 10% of total revenue | Customer | 0 | 0 |
Percentage of revenue from top customer |  |  | 9.00%
Percentage of trade receivables of top customer |  |  | 7.10%

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- Definition The percentage of the entity's revenue. [Refer: Revenue] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 34 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_34&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition Percentage of entity's trade receivables. + References No definition available. + Details
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- Details
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