Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

+ Details

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- Definition

The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 145
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_145_a&doctype=Standard
-URIDate 2017-03-09

+ Details

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- Definition

The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 57
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_57_a&doctype=Standard
-URIDate 2017-03-09

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Post-Employment Benefits - Additional Information (Detail) - BRL (R$) R$ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of defined benefit plans [line items]
Defined benefit plan assets	R$ 18,808	R$ 17,588	R$ 16,520
Medical care cost [member]
Disclosure of defined benefit plans [line items]
Percentage of actuarial method assumption	8.16%
Actuarial assumption of retirement age [member]
Disclosure of defined benefit plans [line items]
Percentage of actuarial method assumption	3.00%
ITAU UNIBANCO HOLDING [Member]
Disclosure of defined benefit plans [line items]
Defined benefit plan assets	R$ 11	12
ITAU UNIBANCO HOLDING [Member] \| Real Estate [Member]
Disclosure of defined benefit plans [line items]
Defined benefit plan assets	R$ 487	R$ 531