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v3.19.1

Post-employment Benefits - Summary of Main Assumptions Used in Actuarial Valuation of Retirement Plans (Parenthetical) (Detail) | 12 Months Ended
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Dec. 31, 2018
Disclosure of defined benefit plans [abstract] |
Increase in probabilities of survival | 10.00%

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- Definition Percentage of Increase in Probabilities of Survival + References No definition available. + Details
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