XML 125 R45.htm IDEA: XBRL DOCUMENT v3.24.0.1
Related Party Transactions (Tables)
 12 Months Ended
Dec. 31, 2023
Related Party Transactions [Abstract]  
Schedule of Related Party Electric Power Supply Agreements The following table presents the specified performance period, average price per MWh, and amount of MWhs included in the agreements:
IPA Procurement EventPerformance PeriodMWhsAverage Price per MWh
April 2019January 2020 – December 2021288,000$35 
September 2019April 2020 – November 2021170,80029 
September 2020September 2021 – November 2022204,80031 
April 2021July 2022 – November 202233,60034 
September 2021January 2022 – September 2023136,00037 
Schedule of Affiliate Receivables and Payables The following table presents the affiliate balances related to income taxes for Ameren Missouri and Ameren Illinois as of December 31, 2023 and 2022:
20232022
Ameren MissouriAmeren IllinoisAmeren MissouriAmeren Illinois
Income taxes payable to parent(a)
$— $2 $— $50 
Income taxes receivable from parent(b)
56 22 39 — 
(a)Included in “Accounts payable – affiliates” on the balance sheet.
(b)Included in “Accounts receivable – affiliates” on the balance sheet
Schedule of Capital Contributions
The following table presents cash capital contributions received from Ameren (parent) by Ameren Missouri and Ameren Illinois for the years ended December 31, 2023, 2022, and 2021:
202320222021
Ameren Missouri(a)
$— $— $207 
Ameren Illinois(a)
91 15 262 
(a)Includes capital contributions made as a result of the tax allocation agreement.
Schedule of Related Party Transactions
The following table presents the impact on Ameren Missouri and Ameren Illinois of related-party transactions for the years ended December 31, 2023, 2022, and 2021. It is based primarily on the agreements discussed above and the money pool arrangements discussed in Note 4 – Short-term Debt and Liquidity.
AgreementIncome Statement Line ItemAmeren
Missouri		Ameren
Illinois
Ameren Missouri power supply agreementsOperating Revenues2023$2 $(a)
with Ameren Illinois20229 (a)
  202116 (a)
Ameren Missouri and Ameren IllinoisOperating Revenues202332 (b)
rent and facility services202225 (b)
  202126 1 
Ameren Missouri and Ameren IllinoisOperating Revenues2023(b)2 
miscellaneous support services2022(b)2 
2021(b)5 
Total Operating Revenues2023$34 $2 
202234 2 
  202142 6 
Ameren Illinois power supplyPurchased Power2023$(a)$2 
agreements with Ameren Missouri2022(a)9 
  2021(a)16 
Ameren Missouri and Ameren IllinoisPurchased Power20232 1 
transmission services from ATXI20221 (b)
20214 1 
Total Purchased Power2023$2 $3 
20221 9 
20214 17 
Ameren Missouri and Ameren IllinoisOther Operations and 2023$(b)$3 
rent and facility servicesMaintenance2022(b)3 
20211 4 
Ameren Services support servicesOther Operations and2023148 138 
agreementMaintenance2022150 141 
  2021147 137 
Total Other Operations and2023$148 $141 
Maintenance Expenses2022150 144 
  2021148 141 
Money pool borrowings (advances)(Interest Charges)2023$(b)$(b)
Other Income, Net2022(b)(b)
  2021(b)(b)
(a)Not applicable.
(b)Amount less than $1 million.