XML 172 R155.htm IDEA: XBRL DOCUMENT v3.22.1
Employee benefits (Details 6)
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Employee benefits [Line Items]        
Actuarial assumption of discount rates 5.67%   3.65% 3.68%
Voluntary retirement rate [Abstract]        
Actuarial assumption of expected rates of salary increases 3.00% 3.00% 3.00%  
Retirement age [Abstract]        
Mortality rate RV - 2014 RV - 2014 RV - 2014  
Men [Member]        
Voluntary retirement rate [Abstract]        
Actuarial assumption voluntary retirement rate 6.49% 6.49% 6.49%  
Retirement age [Abstract]        
Actuarial assumption of retirement age 65 years 65 years 65 years  
Women [Member]        
Voluntary retirement rate [Abstract]        
Actuarial assumption voluntary retirement rate 6.49% 6.49% 6.49%  
Retirement age [Abstract]        
Actuarial assumption of retirement age 60 years 60 years 60 years