Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable no allowance	$ 151	$ 280
Loans, net of unearned income	97,009	98,379
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	56,306	56,033
Total Investor Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	8,379	8,850
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	32,324	33,496
Collateral Dependent Member \| Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	162	220
Collateral Dependent Member \| Total Investor Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income		92
residential real estate and home equity loan and lines \| Collateral Dependent Member \| Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	105	93
Consumer Unsecured Loans sold in period
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivables, book balance sold in period	1,200	284
Allowance for loan losses, related to loans sold prior to sale	94	27
Financing Receiable, Allowance for Credit loss, writeoff on loans sold	63	35
Allowance for loans sold	$ 31
Loss on sale of loans recorded through provision expense		$ 8

Allowance for loan losses, related to loans sold prior to sale

No definition available.

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Namespace Prefix:	rf_
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- Definition

Financing Receiable, Allowance for Credit loss, writeoff on loans sold

+ References

No definition available.

+ Details

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- Definition

Financing Receivables, book balance sold in period

+ References

No definition available.

+ Details

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- Definition

Loss on sale of loans recorded through provision expense

+ References

No definition available.

+ Details

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- 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.

+ References

No definition available.

+ Details

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- Definition

Amount of reduction of allowance reserve for credit loss arising from sale of loan and lease portfolios.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

+ Details

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- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481990/310-10-45-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-4

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- Details

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