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Trade Accounts Receivable - Summary of Movements of Bad Debt Expense in Credit Loss (Detail) - Trade receivables [Member] - MXN ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Disclosure Of Trade Accounts Receivable [Line Items]      
Beginning balance $ (31,528) $ (30,622) $ (136,415)
Bad debt expense (25,289) (12,006) (14,327)
Write-offs     105,236
Reversal of bad debts 8,142 11,100 14,884
Ending balance $ (48,675) $ (31,528) $ (30,622)