Number of days the disconnection suspension period is extended past the Illinois public health emergency end date.

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- Definition

Rate And Regulatory Matters [Line Items]

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

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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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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).

+ References

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Rate And Regulatory Matters (Narrative-Illinois) (Detail) - Ameren Illinois Company - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Feb. 29, 2020	Jun. 30, 2020	Mar. 31, 2020
Rate And Regulatory Matters [Line Items]
Disconnection suspension extension period			60 days
Pending Rate Case \| Natural Gas
Rate And Regulatory Matters [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 102
Revenues	$ 46
Public Utilities, Requested Return on Equity, Percentage			10.50%
Public Utilities, Requested Equity Capital Structure, Percentage			54.10%
Rate Base			$ 2,100
Subsequent Event \| Pending Rate Case \| IEIMA \| Electric Distribution
Rate And Regulatory Matters [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 45