Short-Term Debt and Liquidity (Tables)

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Schedule of Short-term Debt

The following table presents commercial paper outstanding, net of issuance discounts, as of March 31, 2024, and December 31, 2023. There were no borrowings outstanding under the Credit Agreements as of March 31, 2024, or December 31, 2023.

	March 31, 2024		December 31, 2023
Ameren (parent)	$	—	$	—
Ameren Missouri	444		170
Ameren Illinois	424		366
Ameren consolidated	$	868	$	536

The following table summarizes the activity and relevant interest rates for Ameren (parent)’s, Ameren Missouri’s, and Ameren Illinois’ commercial paper issuances and borrowings under the Credit Agreements in the aggregate for the three months ended March 31, 2024 and 2023:

	Ameren (parent)			Ameren Missouri			Ameren Illinois			Ameren Consolidated
2024
Average daily amount outstanding	$	—		$	135		$	336		$	471
Weighted-average interest rate	—		%	5.53		%	5.58		%	5.57		%
Peak amount outstanding during period(a)	$	—		$	444		$	425		$	869
Peak interest rate	—		%	5.68		%	5.68		%	5.68		%
2023
Average daily amount outstanding	$	506		$	436		$	233		$	1,175
Weighted-average interest rate	4.89		%	4.86		%	4.89		%	4.88		%
Peak amount outstanding during period(a)	$	728		$	592		$	325		$	1,381
Peak interest rate	5.55		%	5.55		%	5.60		%	5.60		%

(a)The timing of peak outstanding commercial paper issuances and borrowings under the Credit Agreements varies by company. Therefore, the sum of individual company peak amounts may not equal the Ameren consolidated peak amount for the period.