Medium- And Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Fair value fixed-to-floating rate swap	3.79%
Total FHLB borrowings	$ 15,000
Short-term borrowings	11,016	$ 3,211
Potential future borrowings	987
Unamortized debt issuance cost	8	9
Subsidiaries
Debt Instrument [Line Items]
Floating-rate FHLB advances	$ 4,017	$ 0

Fair value fixed-to-floating rate swap

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- Definition

Short-term advances

+ References

No definition available.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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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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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 210
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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

No definition available.

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