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Investments - Summary of Components of Consideration Paid for Interest (Parenthetical) (Detail) R$ in Millions	12 Months Ended
	Dec. 31, 2018 BRL (R$)
Disclosure of detailed information about investment property [abstract]
Repayments of debt	R$ 5
Future repayments of debt	16
Deposited in an escrow repayment	R$ 3

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- Definition

Deposited in an escrow repayment

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- Definition

Future Repayments of debt

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- Definition

Repayments of debt1

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