Represents the maximum potential amount of future payments (undiscounted) before one year the seller could be required to make under the credit derivative or each group of similar credit derivatives before reduction for potential recoveries under recourse or collateralization provisions in the credit derivative.

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- Definition

Represents the maximum potential amount of future payments (undiscounted) from one to three years the seller could be required to make under the credit derivative or each group of similar credit derivatives before reduction for potential recoveries under recourse or collateralization provisions in the credit derivative.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Represents the maximum potential amount of future payments (undiscounted) from three to five years the seller could be required to make under the credit derivative or each group of similar credit derivatives before reduction for potential recoveries under recourse or collateralization provisions in the credit derivative.

+ Details

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Period Type:	instant

- Definition

Represents the maximum potential amount of future payments (undiscounted) over five years the seller could be required to make under the credit derivative or each group of similar credit derivatives before reduction for potential recoveries under recourse or collateralization provisions in the credit derivative.

+ Details

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Namespace Prefix:	itub
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Discloses the fair value of the credit derivative (or each group of similar credit derivatives) as of the date of the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5708775-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44DD
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the maximum potential amount of future payments (undiscounted) the seller could be required to make under the credit derivative or each group of similar credit derivatives before reduction for potential recoveries under recourse or collateralization provisions in the credit derivative.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Credit Derivative
-URI http://asc.fasb.org/extlink&oid=6854095

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5708775-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44DD
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ Details

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Period Type:	duration

DERIVATIVE FINANCIAL INSTRUMENTS AND FINANCIAL INSTRUMENTS RELATED TO CREDIT (Details 2) (BRL) In Millions	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Credit Default Swap [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Maximum potential of future payments, gross	3,375
Before 1 year	541
From 1 to 3 years	1,234
From 3 to 5 years	1,184
Over 5 years	416
Fair value		(119)	(103)
Total Return Swap [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Maximum potential of future payments, gross	424
Before 1 year	416
From 1 to 3 years	0
From 3 to 5 years	8
Over 5 years	0
Fair value		(8)	0
Derivative [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Maximum potential of future payments, gross	3,799
Before 1 year	957
From 1 to 3 years	1,234
From 3 to 5 years	1,192
Over 5 years	416
Fair value		(127)	(103)
External Credit Rating, Investment Grade [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Maximum potential of future payments, gross	3,799
Before 1 year	957
From 1 to 3 years	1,234
From 3 to 5 years	1,192
Over 5 years	416
Fair value		(127)	(103)
Total By Risk [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Maximum potential of future payments, gross	3,799
Before 1 year	957
From 1 to 3 years	1,234
From 3 to 5 years	1,192
Over 5 years	416
Fair value		(127)	(103)
Private Entities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Maximum potential of future payments, gross	3,799
Before 1 year	957
From 1 to 3 years	1,234
From 3 to 5 years	1,192
Over 5 years	416
Fair value		(127)	(103)
Total By Entity [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Maximum potential of future payments, gross	3,799
Before 1 year	957
From 1 to 3 years	1,234
From 3 to 5 years	1,192
Over 5 years	416
Fair value		(127)	(103)