Approved rate base

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ 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.

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- Definition

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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- Definition

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
	Jan. 31, 2025	Dec. 31, 2024	Nov. 30, 2024	Dec. 31, 2023	Nov. 30, 2023	Oct. 31, 2023	Dec. 31, 2027	Dec. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Public Utilities, General Disclosures [Line Items]
Capital expenditures										$ 4,319	$ 3,597	$ 3,351
Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Capital expenditures										1,467	$ 1,731	$ 1,601
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]
Multi-year rate plan approved revenue requirement										$ 1,206
Public Utilities, Approved Return on Equity, Percentage										8.72%
Public Utilities, Approved Equity Capital Structure, Percentage										50.00%
Approved rate base		$ 4,200								$ 4,200
Multi-year rate plan requested revenue requirement										1,196
American Illinois Proposed Average Annual Rate Base (in Billions)										4,000
Approved rate increase (decrease), amount										$ 309
IETL \| Electric Distribution \| Ameren Illinois \| Forecast
Public Utilities, General Disclosures [Line Items]
Multi-year rate plan approved revenue requirement							$ 1,422	$ 1,367	$ 1,287
Approved rate base							4,800	4,600	4,400
Multi-year rate plan requested revenue requirement							1,397	1,350	1,282
American Illinois Proposed Average Annual Rate Base (in Billions)							$ 4,700	$ 4,500	$ 4,300
Pending Rate Case \| Electric Distribution \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Cumulative rate increase		$ 158
Percentage of requested equity capital structure		50.00%
Pending Rate Case \| Natural gas \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Capital expenditures						$ 30
Pending Rate Case \| Electric Energy-Efficiency \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Approved rate base			$ 434
Cumulative rate increase			$ 126
Pending Rate Case \| Electric Energy-Efficiency \| Ameren Illinois \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Cumulative rate increase	$ 26
Delivery Service Rate Order \| Natural gas \| Ameren Illinois
Public Utilities, General Disclosures [Line Items]
Cumulative rate increase					$ 140
Delivery Service Rate Order \| Natural gas \| Ameren Illinois \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Return on Equity, Percentage	10.70%
Public Utilities, Approved Equity Capital Structure, Percentage	52.00%
Approved rate base	$ 3,300
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
Final Rate Order \| Natural gas \| Ameren Illinois \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Return on Equity, Percentage	9.44%
Capital expenditures	$ 48