Collateralized loan percentage compared to asset's market value

No definition available.

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- Definition

The change in the interest rate used to adjust for the time value of money for the plan

+ References

No definition available.

+ Details

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of the contributions expected to be paid to the plan during the next five fiscal years beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

No definition available.

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- Definition

Defined Benefit Plan, Future Funding Requirement, Percentage

+ References

No definition available.

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- Definition

Defined Benefit Plan Number of High Quality Bonds Used to Determine Yield Curve

+ References

No definition available.

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
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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.

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
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- Definition

Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
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Retirement Benefits (Narrative) (Details) $ in Millions	12 Months Ended
Retirement Benefits (Narrative) (Details) $ in Millions	Dec. 31, 2023	Dec. 31, 2022 USD ($) bond	Dec. 31, 2021 USD ($)	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan		$ 377	$ 717
Defined Benefit Plan Assumptions Used Calculating Benefit Obligation, Change in Discount Rate		2.55%
Number of high-quality corporate bonds \| bond		850
Defined benefit plan estimated future employer contributions over next five years		$ 170
Collateralized loan percentage compared to asset's market value		103.00%
Securities Loaned		$ 239	374
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan		$ (34)	$ 288
Expected return on plan assets		6.50%	6.50%	7.00%
Pension Benefits \| Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	6.75%
Union Electric Company \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Future funding requirement, percentage		40.00%
Ameren Illinois Company \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Future funding requirement, percentage		50.00%