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- References

No definition available.

Name:	fitb_FairValueOptionLoansHeldAsAssetsAggregateUnpaidPrincipalBalanceAbstract
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Loans held as assets for which the fair value option has been elected, this item represents the aggregate unpaid principal balance of those loans that are in nonaccrual status

No definition available.

Name:	fitb_FairValueOptionLoansHeldAsAssetsAmountInNonaccrualStatusAggregateUnpaidPrincipal
Namespace Prefix:	fitb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Fair value portion of loans receivable including mortgage loans held-for-investment and mortgage loans held-for-sale.

No definition available.

Name:	fitb_FairValuePortionLoansReceivableDisclosure
Namespace Prefix:	fitb_
Data Type:	xbrli:monetaryItemType
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Loans for which the fair value option has been elected, this item represents the aggregate unpaid principal amount

No definition available.

Name:	fitb_LoansUnpaidPrincipal
Namespace Prefix:	fitb_
Data Type:	xbrli:monetaryItemType
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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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- References

No definition available.

Name:	us-gaap_FairValueOptionLoansHeldAsAssetsAbstract
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This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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- References

No definition available.