Pension and Other Employee Obligations - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Disclosure of defined benefit plans [line items]
Net amount recognized relating to defined benefit plan	$ 10,060	$ 10,800
Maximum limit of lump-sum gratuity payment	31	15
Past service cost	538
Amount of fund assets invested	1,041	976
Expected contributions for the year ending March 31, 2018	1,962
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	$ 1,037	973
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	57.00%
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	43.00%
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	$ 9,402	7,973
Philippines [member]
Disclosure of defined benefit plans [line items]
Net amount recognized relating to defined benefit plan	36	2,341
Sri Lanka [member]
Disclosure of defined benefit plans [line items]
Net amount recognized relating to defined benefit plan	$ 622	$ 486

The description of the methods and assumptions used when preparing a sensitivity analysis for significant actuarial assumptions. [Refer: Actuarial assumptions [member]]

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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.

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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
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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

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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

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The amount of deficit in a defined benefit plan. [Refer: Defined benefit plans [member]]

+ References

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The percentage allocation of investments that constitute the fair value of defined benefit plan assets.

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Maximum limit of lump-sum gratuity payment.

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