Debt Maturity Period In Years Of Other Fhlb Advances With Maturities Maximum

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Debt Maturity Period In Years Of Other Fhlb Advances With Maturities Minimum

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Debt maturity in Years of Other FHLB Advances With Maturities Weighted Average

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Number Of Issuances Of Debt

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Weighted average interest rate of debt outstanding.

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The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

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Amount of cash inflow (outflow) from other long-term debt.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Borrowings (Narrative) (Details) $ in Millions	12 Months Ended
Borrowings (Narrative) (Details) $ in Millions	Dec. 31, 2019 USD ($) agreement	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Short-term borrowings	$ 2,050	$ 1,600
Gain (Loss) on Extinguishment of Debt	(16)	$ 0	$ 0
Total Borrowing Capacity with the FHLB	$ 17,500
Debt, Weighted Average Interest Rate	3.40%	3.20%	3.00%
Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.80%
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
FHLB Advances Weighted Average Interest Rate	1.90%	2.60%	1.40%
Debt Maturity Period In Years Of Other FHLB Advances With Maturities Minimum	1 year
Debt Maturity Period In Years Of Other FHLB Advances With Maturities Maximum	8 years
Debt maturity in Years of Other FHLB Advances With Maturities Weighted Average	8 months 12 days
Minimum [Member] \| Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.45%
Maximum [Member] \| Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.75%
Parent Company [Member]
Debt Instrument [Line Items]
Gain (Loss) on Extinguishment of Debt	$ (16)	$ 0	$ 0
Parent Company [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Senior Long-term Debt	$ 500
Parent Company [Member] \| Subordinated Debt [Member]
Debt Instrument [Line Items]
Number Of Issuances Of Debt \| agreement	3
Proceeds from Issuance of Subordinated Long-term Debt		$ 554
Regions Bank [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Redemption	$ 740
Regions Bank [Member] \| Subordinated Debt [Member]
Debt Instrument [Line Items]
Number Of Issuances Of Debt \| agreement	1
Proceeds from Issuance of Subordinated Long-term Debt	$ 495