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Rate And Regulatory Matters (Narrative-Illinois) (Details) - Ameren Illinois Company $ in Millions | 9 Months Ended
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Sep. 30, 2022 USD ($) numberOfProposedPerformanceMetrics
Rate And Regulatory Matters [Line Items] |
Annual investment in energy-efficiency programs | $ 120
Minimum |
Rate And Regulatory Matters [Line Items] |
ICC required RTO cost benefit study duration | 5 years
Maximum |
Rate And Regulatory Matters [Line Items] |
ICC required RTO cost benefit study duration | 10 years
Electric Distribution |
Rate And Regulatory Matters [Line Items] |
Requested Return on Equity Adjustment | 0.24%
Number of Proposed Performance Metrics | numberOfProposedPerformanceMetrics | 7
Electric Distribution | Minimum |
Rate And Regulatory Matters [Line Items] |
Return on equity adjustment | 0.20%
Electric Distribution | Maximum |
Rate And Regulatory Matters [Line Items] |
Return on equity adjustment | 0.60%
Pending Rate Case | Electric Distribution | IEIMA |
Rate And Regulatory Matters [Line Items] |
Public Utilities, Requested Rate Increase (Decrease), Amount | $ 84
Public Utilities, Requested Equity Capital Structure, Percentage | 54.00%
ICC Staff Recommended Rate Increase (Decrease) | $ 61
ICC Staff Recommended Equity Capital Structure, Percentage | 50.00%
Pending Rate Case | Electric Distribution | FEJA energy-efficiency rider |
Rate And Regulatory Matters [Line Items] |
Public Utilities, Requested Rate Increase (Decrease), Amount | $ 17
ICC Staff Recommended Rate Increase (Decrease) | 15
Pending Rate Case | Natural gas |
Rate And Regulatory Matters [Line Items] |
Natural Gas Capital Investment Prudency Challenge | 70
Challenged Recoveries Under the QIP | 3
IETL |
Rate And Regulatory Matters [Line Items] |
Energy Transition Assistance Fund Surcharge | $ 50

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