XML 47 R35.htm IDEA: XBRL DOCUMENT v3.19.2
Trade receivables - Net (Tables)
 12 Months Ended
Dec. 31, 2018
Trade and other receivables [abstract]  
Schedule of Age of Receivables Past Due

Age of receivables that are past due but not impaired is as follows:

 

  At December 31,
  2 0 1 8   2 0 1 7
           
30 - 60 days $ 221,996   $ 72,778
61 - 90 days   57,119     57,629
91 + days   188,262     162,807
Total $        467,377   $ 293,214
Schedule of Allowance for Doubtful Accounts

During the years ended December 31, 2018 and 2017, the movement in the allowance for doubtful accounts was as follows:

 

  2 0 1 8   2 0 1 7
           
Balance at beginning of year $ 199,855   $ 59,095
Provisions   7,486     141,140
Translations effects   24,437     (380)
Balance at end of year $ 231,778   $ 199,855