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Taxes - Summary of Deferred Tax Asset Balance and Respective Changes (Parenthetical) (Detail) - BRL (R$) R$ in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2017
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Deferred tax assets [abstract] |  |  |
Deferred income tax and social contribution assets | R$ 32,781 | R$ 35,869 | R$ 38,202
Deferred income tax and social contribution liabilities | R$ 447 | R$ 391 | R$ (289)

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- Definition Deferred tax assets. + References No definition available. + Details
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- Definition Income tax and social contribution deferred assets. + References No definition available. + Details
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- Definition Income tax and social contribution deferred liabilities. + References No definition available. + Details
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