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v3.19.1

Other Current Monetary Assets - Annual Yield Rates of Time Deposits and Negotiable Certificates of Deposits with Maturities of more Than Three Months (Detail) | Dec. 31, 2018 | Dec. 31, 2017
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Bottom of range [Member] |  |
Disclosure of annual yield rates of other current monetary assets [Line Items] |  |
Time deposits and negotiable certificates of deposit with maturities of more than three months | 0.03% | 0.06%
Top of Range [Member] |  |
Disclosure of annual yield rates of other current monetary assets [Line Items] |  |
Time deposits and negotiable certificates of deposit with maturities of more than three months | 3.05% | 4.15%

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