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Pension and Other Employee Obligations - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Mar. 31, 2017
Disclosure of defined benefit plans [line items] |  |  |
Net amount recognized relating to defined benefit plan | $ 11,293 | $ 10,060 |
Maximum limit of lump-sum gratuity payment | 29 | 31 | $ 14
Past service cost |  | 538 |
Amount of fund assets invested | 1,259 | 1,041 |
Expected contributions for the year ending March 31, 2018 | 1,958 |  |
Life Insurance Corporation of India [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Amount of fund assets invested | 4 | 4 |
Aviva Life Insurance Company Private Limited [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Amount of fund assets invested | $ 1,255 | 1,037 |
Unquoted government securities [member] | Life Insurance Corporation of India [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Fund assets, investment percentage | 40.00% |  |
Unquoted government securities [member] | Aviva Life Insurance Company Private Limited [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Fund assets, investment percentage | 87.00% |  |
Money market instruments [member] | Life Insurance Corporation of India [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Fund assets, investment percentage | 60.00% |  |
Money market instruments [member] | Aviva Life Insurance Company Private Limited [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Fund assets, investment percentage | 13.00% |  |
Previously Reported [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Maximum limit of lump-sum gratuity payment |  |  | $ 15
Discount rate [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Possible change in discount rates | Up to 1% |  |
India [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Net amount recognized relating to defined benefit plan | $ 10,683 | 9,402 |
Philippines [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Net amount recognized relating to defined benefit plan | 29 | 36 |
Sri Lanka [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Net amount recognized relating to defined benefit plan | $ 581 | $ 622 |

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- Definition The description of the methods and assumptions used when preparing a sensitivity analysis for significant actuarial assumptions. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 145 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_145_b&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 147 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_147_b&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 148 -Subparagraph d -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_148_d_iii&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_d&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_57_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of deficit in a defined benefit plan. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard -URIDate 2018-03-16 + Details
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