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- References

No definition available.

Name:	fitb_Settlementenddate
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- References

No definition available.

Name:	fitb_Settlementstartdate
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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.

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Data Type:	xbrli:stringItemType
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Date the debt instrument was repurchased, in CCYY-MM-DD format.

No definition available.

Name:	us-gaap_DebtInstrumentRepurchaseDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

Settlement date of the forward contract indexed to issuer's equity, in CCYY-MM-DD format.

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Additional shared included in the calculation of diluted EPS as a result of the potentially dilutive effect of equity forward arrangements using the reverse treasury stock method.

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Number of stock bought back by the entity at the exercise price or redemption price.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Name:	us-gaap_AcceleratedShareRepurchasesDateAxis=fitb_December152017asrMember
Namespace Prefix:
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Name:	us-gaap_StatementClassOfStockAxis=fitb_March2017repurchaseprogramMember
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Data Type:	na
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Name:	us-gaap_AcceleratedShareRepurchasesDateAxis=fitb_February82018Member
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Data Type:	na
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