BUSINESS DEVELOPMENT (Details 1) (Unibanco and Unibanco Holdings [Member], BRL) In Millions	12 Months Ended
Dec. 31, 2009	Feb. 18, 2009
Unibanco and Unibanco Holdings [Member]
Business Acquisition [Line Items]
Cash and cash equivalents		17,262
Interest-bearing deposits in other banks		770
Securities purchased under resale agreements		26,922
Central Bank compulsory deposits		2,093
Trading assets, at fair value		21,265
Available-for-sale securities, at fair value		18,547
Held-to-maturity securities, at amortized cost		836
Net loans and leases		69,644
Investments in unconsolidated companies - Redecard		3,891
Investments in unconsolidated companies - Others		1,166
Premises and equipment, net		1,155
Intangible assets		13,517
Deferred tax asset, net		1,560
Deferred tax asset for excess tax-deductible goodwill		7,155
Other assets		15,557
Total assets purchased		201,340
Non-interest and interest-bearing deposits		56,762
Securities sold under repurchase agreements		33,545
Short and long-term borrowings		38,813
Other liabilities		45,228
Total liabilities assumed		174,348
Net asset at fair value		26,992
Fair value of non-controlling interests		(1,503)
Shareholders’ equity attributable to Itaú Unibanco		25,489
Purchase price		24,659
Bargain purchase gain	830

The amount of available-for-sale securities at fair value acquired in a business combination.

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The amount of central Bank compulsory deposits acquired in a business combination.

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Amount of deferred tax assets for excess tax-deductible goodwill acquired in a business combination.

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The amount of acquisition cost of a business combination allocated to fair value of non-controlling interests.

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The amount of held-to-maturity securities at amortized cost acquired in a business combination.

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The amount of interest-bearing deposits in other banks acquired in a business combination.

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The amount of investments in unconsolidated companies acquired - others in a business combination.

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The amount of investments in unconsolidated companies - Redecard acquired in a business combination.

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The amount of net loans and leases acquired in a business combination.

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The amount of acquisition cost of a business combination allocated to non-interest and interest-bearing deposits.

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The amount of securities purchased under resale agreements acquired in a business combination.

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The amount of acquisition cost of a business combination allocated to securities sold under repurchase agreements.

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The amount of acquisition cost of a business combination allocated to Short and long-term borrowings.

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The amount of acquisition cost of a business combination allocated to stockholders' equity attributable to reporting entity.

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The amount of trading assets at fair value acquired in a business combination.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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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.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
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-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.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 52
-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.

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The amount of acquisition cost of a business combination allocated to assets acquired.

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 35
-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.

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The amount of cash and cash equivalents acquired in a business combination.

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The amount of acquisition cost of a business combination allocated to prepaid expenses and other current assets. Does not include amounts allocated to cash and cash equivalents, marketable securities, receivables, inventory, and assets not to be used.

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The amount of acquisition cost of a business combination allocated to other current liabilities of the acquired entity. Does not include amounts allocated to the current portion of long-term debt, accounts payable and accrued expenses.

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Amount of deferred tax assets or liabilities for the differences between the values assigned and the tax bases of assets and liabilities in a business combination, net of any valuation allowance for deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph e
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 38
-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.

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The amount of acquisition cost of a business combination allocated to liabilities assumed.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 37
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 98-1
-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.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph e
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 37
-Subparagraph d
-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.

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Amount of the excess of the fair value of acquired net assets over the cost of an acquired business after pro rata reduction of the amounts that otherwise would have been assigned to acquired assets except financial assets other than investments accounted for by the equity method, assets to be disposed of by sale, deferred tax assets, prepaid assets relating to pension and postretirement benefit plans, and other current assets. This amount is considered an extraordinary item and often referred to as negative goodwill. This element is gross of the related tax effect.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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