Loans and advances to customers (Details 2) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance For Loans And Advances To Customers [Abstract]
At the beginning of the year	R$ 24,780,839	R$ 25,455,204
Impairment of loans and advances	16,860,835	15,350,278	R$ 14,721,152
Recovery of credits charged-off as losses	7,034,857	5,507,507	4,144,879
Write-offs	(21,620,965)	(21,532,150)
At the end of the year	R$ 27,055,566	R$ 24,780,839	R$ 25,455,204

Adjustments for impairment loss (reversal of impairment loss) recognised in profit or loss to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Impairment loss (reversal of impairment loss) recognised in profit or loss]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2017-01-01
-Paragraph 20
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2017-03-01&anchor=para_20_b&doctype=Standard
-URIDate 2017-03-09

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