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EMPLOYEE BENEFITS - Defined benefit pension plan - Assumptions used to calculate defined benefit plans (Details) - Defined benefit pension plan	Dec. 31, 2018	Dec. 31, 2017
Brazil
Summary of assumptions used to calculate the defined benefit plans
Average discount rate	9.10%	9.84%
North America
Summary of assumptions used to calculate the defined benefit plans
Rate of increase in compensation	3.00%	3.00%
North America | Minimum
Summary of assumptions used to calculate the defined benefit plans
Average discount rate	3.50%	3.25%
North America | Maximum
Summary of assumptions used to calculate the defined benefit plans
Average discount rate	4.25%	4.25%

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- Definition

The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The expected rate of salary increases used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]]

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