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20. Employees benefits (Details 6)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employees Benefits Details 6
Discount rate	5.35%	5.74%	7.23%
Inflation rate	3.96%	4.87%	6.49%
Expected rate of return on assets	9.52%	10.89%	14.19%
Future salary increase	6.04%	6.97%	8.62%
Mortality table	AT-2000	AT-2000	AT-2000

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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]]

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The expected rate of inflation that is 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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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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Any other material assumption used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Actuarial assumptions [member]; Defined benefit obligation, at present value]

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