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- References

No definition available.

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- References

No definition available.

Name:	fitb_Longtermdebtretained
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OTTI

No definition available.

Name:	fitb_Marketablesecuritiesrealizedgainlossotherthantemporaryimpairments
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Year in which contingent commitments to qualified affordable housing project investments are expected to be paid, in CCYY format.

No definition available.

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Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=114775393&loc=SL49122993-202985

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The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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-Section 50
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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.

No definition available.

Name:	us-gaap_VariableInterestEntityLineItems
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Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 4
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Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember
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Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=us-gaap_LoansReceivableMember
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Data Type:	na
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Name:	us-gaap_FinancialInstrumentAxis=fitb_FifthThirdCommunityDevelopmentCorporationInvestmentsMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_InvestmentTypeAxis=us-gaap_OtherThanSecuritiesInvestmentMember
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