Rate and Regulatory Matters (Regulatory Framework-Missouri) (Details) - Union Electric Company	12 Months Ended
	Dec. 31, 2022 MWh
Public Utilities, General Disclosures [Line Items]
Number of months to complete a regulatory rate review	11 months
PISA Deferral Percentage	85.00%
Depreciation Percentage Not Included in PISA Deferral	15.00%
Sharing Level For Fac	95.00%
Percentage of variance not covered by FAC	5.00%
Amount of Megawatts	102
Frequency Rates Must be Reset to Use the FAC	4 years
Maximum
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage	2.85%
PISA Rate Increase Limit Beginning 2024	2.50%
PISA
Public Utilities, General Disclosures [Line Items]
Amortization Period	20 years