XML 221 R90.htm IDEA: XBRL DOCUMENT v3.20.1
Derivatives - Schedule of Notional Amount of Purchased Credit Derivatives (Detail) - BRL (R$)
R$ in Millions
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Disclosure Of Information About Notional Amounts Of Credit Derivative Portfolios [Line Items]    
Notional amount of credit protection sold R$ (10,444) R$ (6,853)
Notional amount of credit protection purchased with identical underlying amount 2,295 1,471
Net position (8,149) (5,382)
Credit default swaps [member]    
Disclosure Of Information About Notional Amounts Of Credit Derivative Portfolios [Line Items]    
Notional amount of credit protection sold (6,283) (6,853)
Notional amount of credit protection purchased with identical underlying amount 2,295 1,471
Net position (3,988) R$ (5,382)
Total return swap [Member]    
Disclosure Of Information About Notional Amounts Of Credit Derivative Portfolios [Line Items]    
Notional amount of credit protection sold (4,161)  
Net position R$ (4,161)