Approved rate base

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- Definition

The deadline for Ameren Illinois to file a revised Grid Plan with the ICC.

+ References

No definition available.

+ Details

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- Definition

Revenue requirement for the electric energy-efficiency investment

+ References

No definition available.

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- Definition

The length of time the ICC required RTO cost benefit study will cover.

+ References

No definition available.

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- Definition

Multi-year rate plan revenue requirement approved by the ICC.

+ References

No definition available.

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- Definition

Ameren Illinois' requested multi-year rate plan revenue requirement.

+ References

No definition available.

+ Details

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- Definition

Over-Recovery Challenged by the Attorney General

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No definition available.

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- Definition

The maximum percentage of energy allowed to be sourced from renewable resources under the Renewable Solutions Program.

+ References

No definition available.

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- Definition

Requested rate Base

+ References

No definition available.

+ Details

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-13

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- Definition

Percentage of public utility's approved equity to capital, including debt and equity.

+ References

No definition available.

+ Details

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

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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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Percentage of public utility's requested equity to capital, including debt and equity.

+ References

No definition available.

+ Details

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

+ References

No definition available.

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Percentage of public utility's requested return on equity.

+ References

No definition available.

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Rate And Regulatory Matters (Narrative-Illinois) (Details) - USD ($) $ in Millions	1 Months Ended				12 Months Ended
	Dec. 31, 2023	Nov. 30, 2023	Oct. 31, 2023	Jul. 31, 2023	Dec. 31, 2027	Dec. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Public Utilities, General Disclosures [Line Items]
Capital expenditures									$ 3,597	$ 3,351	$ 3,479
Forecast
Public Utilities, General Disclosures [Line Items]
Capital expenditures								$ 1,800
Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Capital expenditures									$ 1,731	$ 1,601	$ 1,432
Ameren Illinois \| Minimum
Public Utilities, General Disclosures [Line Items]
ICC required RTO cost benefit study duration				5 years
Ameren Illinois \| Maximum
Public Utilities, General Disclosures [Line Items]
ICC required RTO cost benefit study duration				10 years
Natural gas
Public Utilities, General Disclosures [Line Items]
Percentage of energy sourced from renewable resources		100.00%
Natural gas \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Percent of requested return on equity	9.89%
Percentage of requested equity capital structure	52.00%
IETL \| Electric Distribution \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Deadline to file a revised grid plan									3 months
IETL \| Electric Distribution \| Ameren Illinois \| Forecast
Public Utilities, General Disclosures [Line Items]
Multi-year rate plan approved revenue requirement					$ 1,255	$ 1,242	$ 1,210	$ 1,162
Public Utilities, Approved Return on Equity, Percentage					8.72%	8.72%	8.72%	8.72%
Public Utilities, Approved Equity Capital Structure, Percentage					50.00%	50.00%	50.00%	50.00%
Approved rate base					$ 3,900	$ 3,900	$ 3,900	$ 3,900
Multi-year rate plan requested revenue requirement					1,420	1,371	1,300	1,214
American Illinois Proposed Average Annual Rate Base (in Billions)					$ 4,900	$ 4,700	$ 4,500	4,200
Approved rate increase (decrease), amount								142
Cumulative rate increase								$ 444
Percent of requested return on equity								9.82%
IEIMA revenue requirement reconciliation adjustment \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Return on Equity, Percentage									5.80%
Final Rate Order \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Electric energy-efficiency revenue requirement		$ 100
Final Rate Order \| Natural gas \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Return on Equity, Percentage		9.44%
Public Utilities, Approved Equity Capital Structure, Percentage		50.00%
Approved rate base		$ 2,850
Cumulative rate increase		112
Capital expenditures	$ 93	$ 93
Pending Rate Case \| Natural gas \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Capital expenditures			$ 53
Amount of over-recovery challenged by the Attorney General			$ 3
IEIMA revenue requirement reconciliation adjustment \| Final Rate Order \| Electric Distribution \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage		50.00%
Approved rate base		$ 3,900
Approved rate increase (decrease), amount		110
FEJA energy-efficiency rider \| Final Rate Order \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Approved rate base		394
Approved rate increase (decrease), amount		$ 24