Commitments And Contingencies (Tables)

6 Months Ended

Jun. 30, 2012

Schedule Of Insurance Coverage At Callaway Energy Center

Type and Source of Coverage	Maximum Coverages			Maximum Assessments for Single Incidents
Public liability and nuclear worker liability:
American Nuclear Insurers	$	375		$	-
Pool participation		12,219	(a)		118	(b)
	$	12,594	(c)	$	118
Property damage:
Nuclear Electric Insurance Ltd.	$	2,750	(d)	$	23
Replacement power:
Nuclear Electric Insurance Ltd	$	490	(e)	$	9
Energy Risk Assurance Company	$	64	(f)	$	-

(a) Provided through mandatory participation in an industrywide retrospective premium assessment program.

(b) Retrospective premium under Price-Anderson. This is subject to retrospective assessment with respect to a covered loss in excess of $375 million in the event of an incident at any licensed United States commercial reactor, payable at $17.5 million per year.

(c) Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of 1954, as amended. A company could be assessed up to $118 million per incident for each licensed reactor it operates with a maximum of $17.5 million per incident to be paid in a calendar year for each reactor. This limit is subject to change to account for the effects of inflation and changes in the number of licensed reactors.

(d) Provides for $500 million in property damage and decontamination, excess property insurance, and premature decommissioning coverage up to $2.25 billion for losses in excess of the $500 million primary coverage.

(e) Provides the replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. Weekly indemnity up to $4.5 million for 52 weeks, which commences after the first eight weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $490 million.

(f) Provides the replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. The coverage commences after the first 52 weeks of insurance coverage from Nuclear Electric Insurance Ltd. and is for a weekly indemnity of $900,000 for 71 weeks in excess of the $3.6 million per week set forth above. Energy Risk Assurance Company is an affiliate and has reinsured this coverage with third-party insurance companies. See Note 8 - Related Party Transactions for more information on this affiliate transaction.

Estimated Natural Gas Commitments

	2012		2013		2014		2015		2016		Thereafter		Total
Ameren	$	211	$	367	$	241	$	131	$	53	$	132	$	1,135
Genco		16		34		3		2		-		-		55

Schedule Of Estimated Capital Costs To Comply With Existing And Known Emissions Related Regulations

	2012		2013 - 2016					2017 - 2021					Total
AMO(a)	$	55	$	325	-	$	400	$	845	-	$	1,030	$	1,225	-	$	1,485
Genco		150		100	-		125		245	-		295		495	-		570
AERG		5		20	-		25		80	-		100		105	-		130
Ameren	$	210	$	445	-	$	550	$	1,170	-	$	1,425	$	1,825	-	$	2,185

(a) Ameren Missouri’s expenditures are expected to be recoverable from ratepayers.

Schedule Of Estimated Obligations For Manufactured Gas Plant Remediation

	Estimate				Recorded
	Low		High		Liability(a)
Ameren	$	102	$	181	$	102
Ameren Missouri		3		4		3
Ameren Illinois		99		177		99

(a) Recorded liability represents the estimated minimum probable obligations, as no other amount within the range was a better estimate.

Schedule Of Asbestors-Related Litigation Pending Lawsuits

Ameren	Ameren Missouri	Ameren  llinois	Genco	Total(a)
4	69	91	(b)	115

(a) Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants.

(b) As of June 30, 2012, eight asbestos-related lawsuits were pending against EEI. The general liability insurance maintained by EEI provides coverage with respect to liabilities arising from asbestos-related claims.

Ameren Missouri [Member]

Schedule Of Insurance Coverage At Callaway Energy Center

Type and Source of Coverage	Maximum Coverages			Maximum Assessments for Single Incidents
Public liability and nuclear worker liability:
American Nuclear Insurers	$	375		$	-
Pool participation		12,219	(a)		118	(b)
	$	12,594	(c)	$	118
Property damage:
Nuclear Electric Insurance Ltd.	$	2,750	(d)	$	23
Replacement power:
Nuclear Electric Insurance Ltd	$	490	(e)	$	9
Energy Risk Assurance Company	$	64	(f)	$	-

(a) Provided through mandatory participation in an industrywide retrospective premium assessment program.

(b) Retrospective premium under Price-Anderson. This is subject to retrospective assessment with respect to a covered loss in excess of $375 million in the event of an incident at any licensed United States commercial reactor, payable at $17.5 million per year.

(c) Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of 1954, as amended. A company could be assessed up to $118 million per incident for each licensed reactor it operates with a maximum of $17.5 million per incident to be paid in a calendar year for each reactor. This limit is subject to change to account for the effects of inflation and changes in the number of licensed reactors.

(d) Provides for $500 million in property damage and decontamination, excess property insurance, and premature decommissioning coverage up to $2.25 billion for losses in excess of the $500 million primary coverage.

(e) Provides the replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. Weekly indemnity up to $4.5 million for 52 weeks, which commences after the first eight weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $490 million.

(f) Provides the replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. The coverage commences after the first 52 weeks of insurance coverage from Nuclear Electric Insurance Ltd. and is for a weekly indemnity of $900,000 for 71 weeks in excess of the $3.6 million per week set forth above. Energy Risk Assurance Company is an affiliate and has reinsured this coverage with third-party insurance companies. See Note 8 - Related Party Transactions for more information on this affiliate transaction.

Schedule Of Estimated Capital Costs To Comply With Existing And Known Emissions Related Regulations

	2012		2013 - 2016					2017 - 2021					Total
AMO(a)	$	55	$	325	-	$	400	$	845	-	$	1,030	$	1,225	-	$	1,485
Genco		150		100	-		125		245	-		295		495	-		570
AERG		5		20	-		25		80	-		100		105	-		130
Ameren	$	210	$	445	-	$	550	$	1,170	-	$	1,425	$	1,825	-	$	2,185

(a) Ameren Missouri’s expenditures are expected to be recoverable from ratepayers.

Schedule Of Estimated Obligations For Manufactured Gas Plant Remediation

	Estimate				Recorded
	Low		High		Liability(a)
Ameren	$	102	$	181	$	102
Ameren Missouri		3		4		3
Ameren Illinois		99		177		99

(a) Recorded liability represents the estimated minimum probable obligations, as no other amount within the range was a better estimate.

Schedule Of Asbestors-Related Litigation Pending Lawsuits

Ameren	Ameren Missouri	Ameren  llinois	Genco	Total(a)
4	69	91	(b)	115

(a) Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants.

(b) As of June 30, 2012, eight asbestos-related lawsuits were pending against EEI. The general liability insurance maintained by EEI provides coverage with respect to liabilities arising from asbestos-related claims.

Ameren Illinois Company [Member]

Schedule Of Estimated Obligations For Manufactured Gas Plant Remediation

	Estimate				Recorded
	Low		High		Liability(a)
Ameren	$	102	$	181	$	102
Ameren Missouri		3		4		3
Ameren Illinois		99		177		99

Schedule Of Asbestors-Related Litigation Pending Lawsuits

Ameren	Ameren Missouri	Ameren  llinois	Genco	Total(a)
4	69	91	(b)	115

(a) Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants.

(b) As of June 30, 2012, eight asbestos-related lawsuits were pending against EEI. The general liability insurance maintained by EEI provides coverage with respect to liabilities arising from asbestos-related claims.

Ameren Energy Generating Company [Member]

Schedule Of Estimated Capital Costs To Comply With Existing And Known Emissions Related Regulations

	2012		2013 - 2016					2017 - 2021					Total
AMO(a)	$	55	$	325	-	$	400	$	845	-	$	1,030	$	1,225	-	$	1,485
Genco		150		100	-		125		245	-		295		495	-		570
AERG		5		20	-		25		80	-		100		105	-		130
Ameren	$	210	$	445	-	$	550	$	1,170	-	$	1,425	$	1,825	-	$	2,185

(a) Ameren Missouri’s expenditures are expected to be recoverable from ratepayers.

Schedule Of Asbestors-Related Litigation Pending Lawsuits

Ameren	Ameren Missouri	Ameren  llinois	Genco	Total(a)
4	69	91	(b)	115

(a) Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants.

(b) As of June 30, 2012, eight asbestos-related lawsuits were pending against EEI. The general liability insurance maintained by EEI provides coverage with respect to liabilities arising from asbestos-related claims.