Amount of megawatts

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The percentage of retail sales from renewable sources required by the Missouri renewable energy standard.

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The percentage of retail sales from solar sources required by the Missouri renewable energy standard.

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Number of months to complete a rate proceeding.

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The number of countries being investigated by the Department of Commerce related to solar panel imports.

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- Definition

The PISA rate increase limitation to take effect beginning in 2024.

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

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Rate And Regulatory Matters [Line Items]

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- Definition

Value established for a utility on which the entity is allowed to earn a particular rate of return

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No definition available.

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

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No definition available.

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- Definition

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

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

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Percentage of public utility's requested return on equity.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Rate And Regulatory Matters (Narrative-Missouri) (Details) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2022 USD ($)	Jun. 30, 2022 MWh	Mar. 31, 2022 MWh	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) numberOfCountriesInvestigatedByTheDOC	Sep. 30, 2021 USD ($)
Rate And Regulatory Matters [Line Items]
Revenues	$ 2,306			$ 1,811	$ 5,911	$ 4,849
Union Electric Company
Rate And Regulatory Matters [Line Items]
Missouri Renewable Energy Standard Percentage					15.00%
Missouri Renewable Energy Standard Percentage - Solar					2.00%
Number of Countries Investigated by the DOC \| numberOfCountriesInvestigatedByTheDOC					4
Union Electric Company \| Pending Rate Case \| Electric
Rate And Regulatory Matters [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount					$ 316
Public Utilities, Requested Return on Equity, Percentage					10.20%
Public Utilities, Requested Equity Capital Structure, Percentage					51.90%
Rate Base					$ 11,600
Months to complete a rate proceeding					11 months
Union Electric Company \| Wind Generation Facility
Rate And Regulatory Matters [Line Items]
Amount of Megawatts \| MWh		200	150
Union Electric Company \| Final Rate Order \| Electric \| MEEIA 2019 [Domain]
Rate And Regulatory Matters [Line Items]
Revenues	$ 12			$ 9
Union Electric Company \| Maximum
Rate And Regulatory Matters [Line Items]
PISA Rate Increase Limit Beginning 2024					2.50%
Public Utilities, Approved Rate Increase (Decrease), Percentage					2.85%
Percentage of energy sourced from renewable resources					100.00%