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Pension and Other Employee Obligations - Sensitivity of Defined Benefit Obligation to a Change in Each Significant Actuarial Assumption (Detail) | Mar. 31, 2019
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India [member] | Discount rate [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity of defined benefit obligation due to a possible increase in assumption | (4.70%)
Sensitivity of defined benefit obligation due to a possible decrease in assumption | 5.20%
India [member] | Salary escalation [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity of defined benefit obligation due to a possible increase in assumption | 4.10%
Sensitivity of defined benefit obligation due to a possible decrease in assumption | (3.90%)
Philippines [member] | Discount rate [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity of defined benefit obligation due to a possible increase in assumption | (0.90%)
Sensitivity of defined benefit obligation due to a possible decrease in assumption | 1.00%
Philippines [member] | Salary escalation [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity of defined benefit obligation due to a possible increase in assumption | 0.50%
Sensitivity of defined benefit obligation due to a possible decrease in assumption | (0.50%)
Sri Lanka [member] | Discount rate [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity of defined benefit obligation due to a possible increase in assumption | (4.20%)
Sensitivity of defined benefit obligation due to a possible decrease in assumption | 4.60%
Sri Lanka [member] | Salary escalation [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity of defined benefit obligation due to a possible increase in assumption | 4.20%
Sensitivity of defined benefit obligation due to a possible decrease in assumption | (3.90%)

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