Short-Term Debt And Liquidity Short-Term Debt and Liquidity (Tables)

3 Months Ended

Mar. 31, 2014

Schedule of Commercial paper [Abstract]

Schedule of Short-term Debt [Table Text Block]

The following table summarizes the commercial paper activity and relevant interest rates under Ameren’s (parent) and Ameren Missouri’s commercial paper programs for the three months ended March 31, 2014, and 2013:

	Ameren (parent)			Ameren Missouri			Ameren Consolidated
2014
Average daily commercial paper outstanding	$	339		$	200		$	539
Weighted-average interest rate	0.45		%	0.45		%	0.45		%
Peak commercial paper during period(a)	$	452		$	290		$	700
Peak interest rate	0.75		%	0.70		%	0.75		%
2013
Average daily commercial paper outstanding	$	2		$	—		$	2
Weighted-average interest rate	0.80		%	—		%	0.80		%
Peak commercial paper during period(a)	$	21		$	—		$	21
Peak interest rate	0.85		%	—		%	0.85		%

(a) The timing of peak commercial paper issuances varies by company, and therefore the amounts presented by company might not equal the Ameren Consolidated peak commercial paper issuances for the period.