$AEE
AMEREN CORP Stock $aee

$aee Overview Financials Valuation SEC Filings Company Website

2011 Q4 Form 8-K Financial Statement

#000100291013000092 Filed on October 17, 2013

Income Statement

Concept	2011 Q4	2011 Q3	2011 Q2
Revenue	$1.296B	$1.876B	$1.458B
YoY Change	-24.03%	-17.25%	-15.48%
Cost Of Revenue	$327.0M	$378.0M	$316.0M
YoY Change	-16.79%	-11.48%	-9.97%
Gross Profit	$1.251B	$1.890B	$1.465B
YoY Change	-4.72%	2.72%	6.62%
Gross Profit Margin	96.53%	100.75%	100.48%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$44.00M	$185.0M	$186.0M
YoY Change	-72.15%	-7.96%	-5.58%
% of Gross Profit	3.52%	9.79%	12.7%
Operating Expenses	$1.102B	$1.718B	$1.465B
YoY Change	-1.17%	47.85%	40.46%
Operating Profit	$91.00M	$494.0M	$270.0M
YoY Change	-54.04%	455.06%	-18.43%
Interest Expense	-$107.0M	$113.0M	$104.0M
YoY Change	-10.83%	-186.92%	-190.43%
% of Operating Profit	-117.58%	22.87%	38.52%
Other Income/Expense, Net	$2.000M	$13.00M	$12.00M
YoY Change	-66.67%	-7.14%	-45.45%
Pretax Income	$43.00M	$450.0M	$224.0M
YoY Change	-48.81%	-1766.67%	-5.88%
Income Tax	$17.00M	$163.0M	$85.00M
% Of Pretax Income	39.53%	36.22%	37.95%
Net Earnings	$25.00M	$285.0M	$138.0M
YoY Change	-51.92%	-270.66%	-9.21%
Net Earnings / Revenue	1.93%	15.19%	9.47%
Basic Earnings Per Share
Diluted Earnings Per Share	$103.2K	$1.179M	$572.1K
COMMON SHARES
Basic Shares Outstanding		241.7M shares	241.2M shares
Diluted Shares Outstanding

Balance Sheet

Concept	2011 Q4	2011 Q3	2011 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$255.0M	$522.0M	$378.0M
YoY Change	-53.21%	-14.14%	-25.3%
Cash & Equivalents	$248.0M	$522.0M	$378.0M
Short-Term Investments
Other Short-Term Assets	$151.0M	$702.0M	$815.0M
YoY Change	-83.42%	-19.77%	-16.32%
Inventory	$550.0M	$734.0M	$654.0M
Prepaid Expenses
Receivables	$424.0M	$575.0M	$507.0M
Other Receivables	$48.00M	$147.0M	$249.0M
Total Short-Term Assets	$5.737B	$2.680B	$2.603B
YoY Change	98.51%	-14.1%	-8.02%
LONG-TERM ASSETS
Property, Plant & Equipment	$14.85B	$17.87B	$17.95B
YoY Change	-16.83%	1.23%	1.12%
Goodwill	$411.0M
YoY Change	0.0%
Intangibles	$7.000M
YoY Change	0.0%
Long-Term Investments	$357.0M	$330.0M	$356.0M
YoY Change	5.93%	4.76%	23.18%
Other Assets	$760.0M	$2.056B	$2.072B
YoY Change	-62.25%	-3.06%	-1.57%
Total Long-Term Assets	$17.99B	$20.68B	$20.79B
YoY Change	-12.78%	0.8%	-1.41%
TOTAL ASSETS
Total Short-Term Assets	$5.737B	$2.680B	$2.603B
Total Long-Term Assets	$17.99B	$20.68B	$20.79B
Total Assets	$23.72B	$23.36B	$23.39B
YoY Change	0.9%	-1.16%	-2.19%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$693.0M	$410.0M	$482.0M
YoY Change	6.45%	-0.97%	3.66%
Accrued Expenses	$101.0M	$159.0M	$107.0M
YoY Change	-5.61%	-8.62%	-13.01%
Deferred Revenue
YoY Change
Short-Term Debt	$148.0M	$350.0M	$337.0M
YoY Change	-44.98%	180.0%
Long-Term Debt Due	$179.0M	$178.0M	$5.000M
YoY Change	15.48%	-49.72%	-98.59%
Total Short-Term Liabilities	$3.373B	$1.848B	$1.727B
YoY Change	78.65%	-3.45%	-1.88%
LONG-TERM LIABILITIES
Long-Term Debt	$5.853B	$6.682B	$7.054B
YoY Change	-19.96%	-7.95%	-7.83%
Other Long-Term Liabilities	$424.0M	$3.294B	$3.459B
YoY Change	-87.72%	-6.37%	-0.8%
Total Long-Term Liabilities	$6.277B	$9.976B	$10.51B
YoY Change	-41.7%	-7.43%	-5.63%
TOTAL LIABILITIES
Total Short-Term Liabilities	$3.373B	$1.848B	$1.727B
Total Long-Term Liabilities	$6.277B	$9.976B	$10.51B
Total Liabilities	$9.650B	$15.36B	$15.60B
YoY Change	-38.85%	-3.26%	-2.02%
SHAREHOLDERS EQUITY
Retained Earnings	$2.369B
YoY Change
Common Stock	$2.000M
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$7.919B	$7.997B	$7.788B
YoY Change
Total Liabilities & Shareholders Equity	$23.72B	$23.36B	$23.39B
YoY Change	0.9%	-1.16%	-2.19%

Cashflow Statement

Concept	2011 Q4	2011 Q3	2011 Q2
OPERATING ACTIVITIES
Net Income	$25.00M	$285.0M	$138.0M
YoY Change	-51.92%	-270.66%	-9.21%
Depreciation, Depletion And Amortization	$44.00M	$185.0M	$186.0M
YoY Change	-72.15%	-7.96%	-5.58%
Cash From Operating Activities	$313.0M	$666.0M	$339.0M
YoY Change	-4.28%	-8.01%	-13.52%
INVESTING ACTIVITIES
Capital Expenditures	-$140.0M	-$263.0M	-$287.0M
YoY Change	-57.45%	24.06%	11.67%
Acquisitions
YoY Change
Other Investing Activities	-$157.0M	$6.000M	$49.00M
YoY Change	-1844.44%	-250.0%	250.0%
Cash From Investing Activities	-$297.0M	-$257.0M	-$238.0M
YoY Change	-7.19%	18.98%	-2.06%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-283.0M	-265.0M	-296.0M
YoY Change	304.29%	-34.73%	9766.67%
NET CHANGE
Cash From Operating Activities	313.0M	666.0M	339.0M
Cash From Investing Activities	-297.0M	-257.0M	-238.0M
Cash From Financing Activities	-283.0M	-265.0M	-296.0M
Net Change In Cash	-267.0M	144.0M	-195.0M
YoY Change	323.81%	41.18%	-233.56%
FREE CASH FLOW
Cash From Operating Activities	$313.0M	$666.0M	$339.0M
Capital Expenditures	-$140.0M	-$263.0M	-$287.0M
Free Cash Flow	$453.0M	$929.0M	$626.0M
YoY Change	-30.95%	-0.75%	-3.54%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2011Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-50000000	USD
CY2012Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	533000000	USD
CY2011Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	592000000	USD
CY2012Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	354000000	USD
CY2011Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	424000000	USD
CY2012Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	70000000	USD
CY2011Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	76000000	USD
CY2011Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	7868000000	USD
CY2012Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-8000000	USD
CY2011Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	211000000	USD
CY2012Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	155000000	USD
CY2011Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	5598000000	USD
CY2012Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	5616000000	USD
CY2012	us-gaap	Adjustment For Amortization AdjustmentForAmortization	83000000	USD
CY2011	us-gaap	Adjustment For Amortization AdjustmentForAmortization	61000000	USD
CY2010	us-gaap	Adjustment For Amortization AdjustmentForAmortization	54000000	USD
CY2011	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	13000000	USD
CY2010	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11000000	USD
CY2012	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	22000000	USD
CY2012Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	17000000	USD
CY2011Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	20000000	USD
CY2012	aee	Disposal Group Including Discontinued Operation Other Income Loss DisposalGroupIncludingDiscontinuedOperationOtherIncomeLoss		USD
CY2011Q4	us-gaap	Assets Current AssetsCurrent	5737000000	USD
CY2012Q4	us-gaap	Assets Current AssetsCurrent	3585000000	USD
CY2011Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	492000000	USD
CY2012	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	20000000	USD
CY2011	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	16000000	USD
CY2010	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	16000000	USD
CY2011	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3000000	USD
CY2012	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4000000	USD
CY2010	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	13000000	USD
CY2012	us-gaap	Asset Impairment Charges AssetImpairmentCharges		USD
CY2011	us-gaap	Asset Impairment Charges AssetImpairmentCharges	123000000	USD
CY2010	us-gaap	Asset Impairment Charges AssetImpairmentCharges	64000000	USD
CY2010Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	403000000	USD
CY2011Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	369000000	USD
CY2012Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	375000000	USD
CY2011	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	22000000	USD
CY2012	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	20000000	USD
CY2011Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	5000000	USD
CY2011	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred		USD
CY2012	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred		USD
CY2012	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	6000000	USD
CY2011	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	2000000	USD
CY2011	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-54000000	USD
CY2012	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-8000000	USD
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CY2012Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	375000000	USD
CY2011Q4	us-gaap	Assets Assets	23723000000	USD
CY2012Q4	us-gaap	Assets Assets	22219000000	USD
CY2012Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	435000000	USD
CY2011Q4	us-gaap	Assets Of Disposal Group Including Discontinued Operation Current AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent	3718000000	USD
CY2012Q4	us-gaap	Assets Of Disposal Group Including Discontinued Operation Current AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent	1600000000	USD
CY2012Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	281000000	USD
CY2011Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	261000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	38000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	24000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	14000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	32000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	35000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	78000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	79000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	23000000	USD
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CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost	133000000	USD
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CY2010	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	5000000	USD
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CY2011	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	5000000	USD
CY2010	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	4000000	USD
CY2011	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	4000000	USD
CY2012	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	2000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Gross Unrealized Losses1 AvailableForSaleSecuritiesGrossUnrealizedLosses1	11000000	USD
CY2011Q4	us-gaap	Available For Sale Securities Gross Unrealized Losses1 AvailableForSaleSecuritiesGrossUnrealizedLosses1	12000000	USD
CY2012Q4	us-gaap	Availableforsale Securities Continuous Unrealized Loss Position12 Months Or Longer Aggregate Losses2 AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses2	10000000	USD
CY2012Q4	us-gaap	Availableforsale Securities Continuous Unrealized Loss Position Aggregate Losses2 AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLosses2	11000000	USD
CY2012Q4	us-gaap	Availableforsale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses2 AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses2	1000000	USD
CY2012Q4	us-gaap	Availableforsale Securities Gross Unrealized Gain AvailableforsaleSecuritiesGrossUnrealizedGain	138000000	USD
CY2011Q4	us-gaap	Availableforsale Securities Gross Unrealized Gain AvailableforsaleSecuritiesGrossUnrealizedGain	108000000	USD
CY2012	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	103000000	USD
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CY2011Q4	us-gaap	Capital Leased Assets Gross CapitalLeasedAssetsGross	229000000	USD
CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Due CapitalLeasesFutureMinimumPaymentsDue	588000000	USD
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CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Due In Five Years CapitalLeasesFutureMinimumPaymentsDueInFiveYears	33000000	USD
CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Due In Four Years CapitalLeasesFutureMinimumPaymentsDueInFourYears	33000000	USD
CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Due In Three Years CapitalLeasesFutureMinimumPaymentsDueInThreeYears	33000000	USD
CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Due In Two Years CapitalLeasesFutureMinimumPaymentsDueInTwoYears	32000000	USD
CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Due Thereafter CapitalLeasesFutureMinimumPaymentsDueThereafter	425000000	USD
CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Interest Included In Payments CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments	284000000	USD
CY2012Q4	us-gaap	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments	304000000	USD
CY2011Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	248000000	USD
CY2012Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	184000000	USD
CY2010Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	538000000	USD
CY2009Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	622000000	USD
CY2011Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	255000000	USD
CY2010Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	545000000	USD
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CY2010	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-77000000	USD
CY2012	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations		USD
CY2011	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	-100000000	USD
CY2010	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	-106000000	USD
CY2010	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-81000000	USD
CY2011	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-99000000	USD
CY2012	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-157000000	USD
CY2012	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	291000000	USD
CY2010	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	420000000	USD
CY2011	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	366000000	USD
CY2011Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	104000000	USD
CY2012Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	61000000	USD
CY2011Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2012Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2012Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	400000000	shares
CY2012Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	242600000	shares
CY2011Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	242600000	shares
CY2010Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	240400000	shares
CY2009Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	237400000	shares
CY2012Q4	us-gaap	Common Stock Value CommonStockValue	2000000	USD
CY2011Q4	us-gaap	Common Stock Value CommonStockValue	2000000	USD
CY2012	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	205000000	USD
CY2010	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	247000000	USD
CY2011	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	206000000	USD
CY2012	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	260000000	USD
CY2011	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	253000000	USD
CY2011	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	486000000	USD
CY2010	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	135000000	USD
CY2012	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-932000000	USD
CY2011	us-gaap	Concentration Risk Credit Risk Financial Instrument Maximum Exposure ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure	156000000	USD
CY2012	us-gaap	Concentration Risk Credit Risk Financial Instrument Maximum Exposure ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure	23000000	USD
CY2011	us-gaap	Cost Of Goods Sold Depreciation Depletion And Amortization CostOfGoodsSoldDepreciationDepletionAndAmortization	646000000	USD
CY2012	us-gaap	Cost Of Goods Sold Depreciation Depletion And Amortization CostOfGoodsSoldDepreciationDepletionAndAmortization	667000000	USD
CY2010	us-gaap	Cost Of Goods Sold Depreciation Depletion And Amortization CostOfGoodsSoldDepreciationDepletionAndAmortization	627000000	USD
CY2011	us-gaap	Cost Of Natural Gas Purchases CostOfNaturalGasPurchases	570000000	USD
CY2010	us-gaap	Cost Of Natural Gas Purchases CostOfNaturalGasPurchases	668000000	USD
CY2012	us-gaap	Cost Of Natural Gas Purchases CostOfNaturalGasPurchases	472000000	USD
CY2011	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	952000000	USD
CY2010	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	1122000000	USD
CY2012	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	780000000	USD
CY2011	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-6000000	USD
CY2012	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	40000000	USD
CY2010	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	3000000	USD
CY2012	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	9000000	USD
CY2011	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-2000000	USD
CY2010	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-1000000	USD
CY2011Q4	us-gaap	Customer Deposits Current CustomerDepositsCurrent	98000000	USD
CY2012Q4	us-gaap	Customer Deposits Current CustomerDepositsCurrent	107000000	USD
CY2011Q4	us-gaap	Decommissioning Fund Investments DecommissioningFundInvestments	357000000	USD
CY2012Q4	us-gaap	Decommissioning Fund Investments DecommissioningFundInvestments	408000000	USD
CY2011Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	358000000	USD
CY2012Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	406000000	USD
CY2010	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	384000000	USD
CY2012	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-6000000	USD
CY2011	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-6000000	USD
CY2010	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-7000000	USD
CY2012	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	61000000	USD
CY2011	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	53000000	USD
CY2010	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	32000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	98000000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	170000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	320000000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	323000000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Asset Retirement Obligations DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations	17000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Asset Retirement Obligations DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations	12000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	3006000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	2712000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	-28000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	-27000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	3176000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	2810000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	-217000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	-251000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	3512000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	3162000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets And Liabilities DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities	73000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets And Liabilities DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities	73000000	USD
CY2011	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	606000000	USD
CY2010	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	590000000	USD
CY2012	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	627000000	USD
CY2011Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	4000000	USD
CY2012Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	7000000	USD
CY2012Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	226000000	USD
CY2011Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	322000000	USD
CY2011	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	167000000	USD
CY2012	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-2487000000	USD
CY2010	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-290000000	USD
CY2010	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	51000000	USD
CY2011	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	65000000	USD
CY2012	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-989000000	USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Accounts Notes And Loans Receivable Net DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet	102000000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Accounts Notes And Loans Receivable Net DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet	108000000	USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Accounts Payable DisposalGroupIncludingDiscontinuedOperationAccountsPayable	133000000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Accounts Payable DisposalGroupIncludingDiscontinuedOperationAccountsPayable	134000000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Cash And Cash Equivalents DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents	7000000	USD
CY2010Q4	us-gaap	Disposal Group Including Discontinued Operation Cash And Cash Equivalents DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents	7000000	USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Cash And Cash Equivalents DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents	25000000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Deferred Tax Assets DisposalGroupIncludingDiscontinuedOperationDeferredTaxAssets		USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Deferred Tax Assets DisposalGroupIncludingDiscontinuedOperationDeferredTaxAssets	385000000	USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Deferred Tax Liabilities DisposalGroupIncludingDiscontinuedOperationDeferredTaxLiabilities		USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Deferred Tax Liabilities DisposalGroupIncludingDiscontinuedOperationDeferredTaxLiabilities	583000000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Interest Expense DisposalGroupIncludingDiscontinuedOperationInterestExpense	56000000	USD
CY2011	us-gaap	Disposal Group Including Discontinued Operation Interest Expense DisposalGroupIncludingDiscontinuedOperationInterestExpense	64000000	USD
CY2010	us-gaap	Disposal Group Including Discontinued Operation Interest Expense DisposalGroupIncludingDiscontinuedOperationInterestExpense	83000000	USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Inventory DisposalGroupIncludingDiscontinuedOperationInventory	134000000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Inventory DisposalGroupIncludingDiscontinuedOperationInventory	162000000	USD
CY2010	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	1578000000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	3478000000	USD
CY2011	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	1048000000	USD
CY2011	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	230000000	USD
CY2010	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	-209000000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	-2431000000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Other Current Assets DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets	97000000	USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Other Current Assets DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets	104000000	USD
CY2012Q4	us-gaap	Disposal Group Including Discontinued Operation Other Current Liabilities DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities	28000000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Other Current Liabilities DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities	26000000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Revenue DisposalGroupIncludingDiscontinuedOperationRevenue	1047000000	USD
CY2010	us-gaap	Disposal Group Including Discontinued Operation Revenue DisposalGroupIncludingDiscontinuedOperationRevenue	1369000000	USD
CY2011	us-gaap	Disposal Group Including Discontinued Operation Revenue DisposalGroupIncludingDiscontinuedOperationRevenue	1278000000	USD
CY2012Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	7000000	USD
CY2011Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent		USD
CY2010Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent		USD
CY2011	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	2.15
CY2010	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.58
CY2012	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	-4.01
CY2011Q1	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.29
CY2011Q4	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.10
CY2012Q2	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.87
CY2011Q3	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	1.18
CY2012Q4	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	-4.76
CY2012Q3	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	1.54
CY2012Q1	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	-1.66
CY2011Q2	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.57
CY2011Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	150000000	USD
CY2011Q4	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	171000000	USD
CY2012Q4	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	131000000	USD
CY2011Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-1000000	USD
CY2012	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.37
CY2011	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.37
CY2010	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.36
CY2010	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2011	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2012	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0.02
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depreciation EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciation	-0.01
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depreciation EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciation	-0.03
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depreciation EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciation	-0.01
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.01
CY2012	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.05
CY2010	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.05
CY2011	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.04
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies EffectiveIncomeTaxRateReconciliationTaxContingencies
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies EffectiveIncomeTaxRateReconciliationTaxContingencies	-0.01
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies EffectiveIncomeTaxRateReconciliationTaxContingencies	0.01
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	-0.01
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	-0.01
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	-0.01
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	-0.01
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	-0.01
CY2011	us-gaap	Electric Utility Revenue ElectricUtilityRevenue	5226000000	USD
CY2012	us-gaap	Electric Utility Revenue ElectricUtilityRevenue	4857000000	USD
CY2010	us-gaap	Electric Utility Revenue ElectricUtilityRevenue	5153000000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Cash Flow Effect Cash Used To Settle Awards EmployeeServiceShareBasedCompensationCashFlowEffectCashUsedToSettleAwards	11000000	USD
CY2010	us-gaap	Employee Service Share Based Compensation Cash Flow Effect Cash Used To Settle Awards EmployeeServiceShareBasedCompensationCashFlowEffectCashUsedToSettleAwards	2000000	USD
CY2011	us-gaap	Employee Service Share Based Compensation Cash Flow Effect Cash Used To Settle Awards EmployeeServiceShareBasedCompensationCashFlowEffectCashUsedToSettleAwards	4000000	USD
CY2012Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	21000000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P20M
CY2011	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5000000	USD
CY2010	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4000000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8000000	USD
CY2012Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	198000000	USD
CY2010	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	189000000	USD
CY2012	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	193000000	USD
CY2011	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	194000000	USD
CY2013Q1	us-gaap	Former Gain Contingency Recognized In Current Period FormerGainContingencyRecognizedInCurrentPeriod	5000000	USD
CY2011Q4	us-gaap	Former Gain Contingency Recognized In Current Period FormerGainContingencyRecognizedInCurrentPeriod	11000000	USD
CY2011	us-gaap	Fuel Costs FuelCosts	911000000	USD
CY2012	us-gaap	Fuel Costs FuelCosts	714000000	USD
CY2010	us-gaap	Fuel Costs FuelCosts	673000000	USD
CY2012	us-gaap	Gain Loss On Sale Of Properties GainLossOnSaleOfProperties		USD
CY2011	us-gaap	Gain Loss On Sale Of Properties GainLossOnSaleOfProperties	3000000	USD
CY2010	us-gaap	Gain Loss On Sale Of Properties GainLossOnSaleOfProperties	5000000	USD
CY2012	us-gaap	Gas Domestic Regulated Revenue GasDomesticRegulatedRevenue	924000000	USD
CY2010	us-gaap	Gas Domestic Regulated Revenue GasDomesticRegulatedRevenue	1116000000	USD
CY2011	us-gaap	Gas Domestic Regulated Revenue GasDomesticRegulatedRevenue	1001000000	USD
CY2011Q4	us-gaap	Goodwill Goodwill	411000000	USD
CY2012Q4	us-gaap	Goodwill Goodwill	411000000	USD
CY2012Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	304000000	USD
CY2011Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	309000000	USD
CY2012	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2010	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	64000000	USD
CY2011	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	123000000	USD
CY2012	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	518000000	USD
CY2011	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	418000000	USD
CY2010	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	483000000	USD
CY2012Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	37000000	USD
CY2011Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	38000000	USD
CY2011Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	265000000	USD
CY2011Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	116000000	USD
CY2012Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	15000000	USD
CY2012Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	161000000	USD
CY2012Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	305000000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Attributable To Noncontrolling Entity IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity	6000000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Attributable To Noncontrolling Entity IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity	9000000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Attributable To Noncontrolling Entity IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity	6000000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	833000000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	669000000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	766000000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	492000000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	524000000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	424000000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	1.73
CY2010	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	2.02
CY2012	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	2.13
CY2012Q4	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	0.06
CY2012Q3	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	1.26
CY2012Q1	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	0.15
CY2012Q2	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	0.66
CY2011Q3	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	1.10
CY2011Q4	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	-0.01
CY2011Q1	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	0.16
CY2011Q2	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	0.48
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	102000000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-1498000000	USD
CY2010	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-341000000	USD
CY2010	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest	3000000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest	-6000000	USD
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest	1000000	USD
CY2010	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-344000000	USD
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	101000000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1492000000	USD
CY2011Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	22000000	USD
CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	50000000	USD
CY2011Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	26000000	USD
CY2011Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	20000000	USD
CY2012Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-440000000	USD
CY2012Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	69000000	USD
CY2012Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1171000000	USD
CY2011Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	33000000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	-6.14
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.42
CY2010	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	-1.44
CY2012Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	-1.81
CY2011Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.13
CY2011Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.08
CY2012Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	-4.82
CY2011Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.09
CY2012Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.28
CY2011Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.11
CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.21
CY2012	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	309000000	USD
CY2010	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	274000000	USD
CY2011	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	245000000	USD
CY2011	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-61000000	USD
CY2012	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1000000	USD
CY2010	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-92000000	USD
CY2010	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	23000000	USD
CY2011	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-31000000	USD
CY2012	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-34000000	USD
CY2011	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	-5000000	USD
CY2012	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	-3000000	USD
CY2010	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	18000000	USD
CY2010	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	70000000	USD
CY2011	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	-36000000	USD
CY2012	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	-41000000	USD
CY2010	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	-9000000	USD
CY2011	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	-100000000	USD
CY2012	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	-23000000	USD
CY2010	us-gaap	Increase Decrease In Insurance Settlements Receivable IncreaseDecreaseInInsuranceSettlementsReceivable	-54000000	USD
CY2011	us-gaap	Increase Decrease In Insurance Settlements Receivable IncreaseDecreaseInInsuranceSettlementsReceivable	1000000	USD
CY2012	us-gaap	Increase Decrease In Insurance Settlements Receivable IncreaseDecreaseInInsuranceSettlementsReceivable		USD
CY2012	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	25000000	USD
CY2011	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	27000000	USD
CY2010	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-19000000	USD
CY2010	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	47000000	USD
CY2011	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-59000000	USD
CY2012	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	6000000	USD
CY2012	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	58000000	USD
CY2010	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	88000000	USD
CY2011	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-68000000	USD
CY2011	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-200000000	USD
CY2010	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	232000000	USD
CY2012	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-30000000	USD
CY2012Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	14000000	USD
CY2011Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	7000000	USD
CY2012	us-gaap	Interest Expense InterestExpense	391000000	USD
CY2010	us-gaap	Interest Expense InterestExpense	415000000	USD
CY2011	us-gaap	Interest Expense InterestExpense	387000000	USD
CY2011	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	28000000	USD
CY2010	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	28000000	USD
CY2012	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	28000000	USD
CY2011	us-gaap	Interest Paid Capitalized InterestPaidCapitalized	30000000	USD
CY2010	us-gaap	Interest Paid Capitalized InterestPaidCapitalized	34000000	USD
CY2012	us-gaap	Interest Paid Capitalized InterestPaidCapitalized	30000000	USD
CY2010	us-gaap	Interest Paid Net InterestPaidNet	494000000	USD
CY2011	us-gaap	Interest Paid Net InterestPaidNet	453000000	USD
CY2012	us-gaap	Interest Paid Net InterestPaidNet	433000000	USD
CY2012Q4	us-gaap	Interest Payable Current InterestPayableCurrent	89000000	USD
CY2011Q4	us-gaap	Interest Payable Current InterestPayableCurrent	91000000	USD
CY2011Q4	us-gaap	Inventory Net InventoryNet	550000000	USD
CY2012Q4	us-gaap	Inventory Net InventoryNet	570000000	USD
CY2010	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	41000000	USD
CY2011	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	36000000	USD
CY2012	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	33000000	USD
CY2012Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	9000000	USD
CY2011Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	23723000000	USD
CY2012Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	22219000000	USD
CY2011Q4	us-gaap	Liabilities Current LiabilitiesCurrent	3373000000	USD
CY2012Q4	us-gaap	Liabilities Current LiabilitiesCurrent	2660000000	USD
CY2011Q4	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Current LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent	1762000000	USD
CY2012Q4	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Current LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent	1166000000	USD
CY2011Q4	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	6429000000	USD
CY2012Q4	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	6990000000	USD
CY2011Q2	us-gaap	Liability For Uncertain Tax Positions Current LiabilityForUncertainTaxPositionsCurrent	39000000	USD
CY2012Q4	us-gaap	Long Term Debt LongTermDebt	6167000000	USD
CY2012Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	355000000	USD
CY2011Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	179000000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	4082000000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	355000000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	681000000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	395000000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	120000000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	534000000	USD
CY2012Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	5802000000	USD
CY2011Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	5853000000	USD
CY2012Q4	us-gaap	Minority Interest MinorityInterest	151000000	USD
CY2011Q4	us-gaap	Minority Interest MinorityInterest	149000000	USD
CY2012	us-gaap	Nature Of Operations NatureOfOperations	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-top:13px;text-indent:24px;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">Ameren, headquartered in St. Louis, Missouri, is a public utility holding company under PUHCA 2005, administered by FERC. Ameren’s primary assets are its equity interests in its subsidiaries. Ameren’s subsidiaries are separate, independent legal entities with separate businesses, assets, and liabilities. These subsidiaries operate, as the case may be, rate-regulated electric generation, transmission and distribution businesses, rate-regulated natural gas transmission and distribution businesses, and merchant electric generation businesses. Dividends on Ameren’s common stock and the payment of other expenses by Ameren depend on distributions made to it by its subsidiaries. Ameren’s principal subsidiaries are listed below. </font></div><table cellpadding="0" cellspacing="0" style="padding-top:13px;font-family:Times New Roman; font-size:10pt;"><tr><td style="width:24px;" rowspan="1" colspan="1"></td><td rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:top" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;padding-left:0px;"><font style="font-family:Arial Narrow;font-size:10pt;">•</font></div></td><td style="vertical-align:top;" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">Union Electric Company, or Ameren Missouri, operates a rate-regulated electric generation, transmission, and distribution business, and a rate-regulated natural gas transmission and distribution business in Missouri. Ameren Missouri was incorporated in Missouri in 1922 and is successor to a number of companies, the oldest of which was organized in 1881. It is the largest electric utility in the state of Missouri. It supplies electric and natural gas service to a </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">24,000</font><font style="font-family:Arial Narrow;font-size:10pt;">-square-mile area in central and eastern Missouri. This area has an estimated population of </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">2.8 million</font><font style="font-family:Arial Narrow;font-size:10pt;"> and includes the Greater St. Louis area. Ameren Missouri supplies electric service to </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">1.2 million</font><font style="font-family:Arial Narrow;font-size:10pt;"> customers and natural gas service to </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">127,000</font><font style="font-family:Arial Narrow;font-size:10pt;"> customers.</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:24px;" rowspan="1" colspan="1"></td><td rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:top" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;padding-left:0px;"><font style="font-family:Arial Narrow;font-size:10pt;">•</font></div></td><td style="vertical-align:top;" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">Ameren Illinois Company, or Ameren Illinois, operates a rate-regulated electric and natural gas transmission and distribution business in Illinois. Ameren Illinois was created by the merger of CILCO and IP with and into CIPS. CIPS was incorporated in Illinois in 1923 and is successor to a number of companies, the oldest of which was organized in 1902. Ameren Illinois supplies electric and natural gas utility service to portions of central and southern Illinois having an estimated population of </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">3.1 million</font><font style="font-family:Arial Narrow;font-size:10pt;"> in an area of </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">40,000</font><font style="font-family:Arial Narrow;font-size:10pt;"> square miles. Ameren Illinois supplies electric service to </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">1.2 million</font><font style="font-family:Arial Narrow;font-size:10pt;"> customers and natural gas service to </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">806,000</font><font style="font-family:Arial Narrow;font-size:10pt;"> customers.</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:24px;" rowspan="1" colspan="1"></td><td rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:top" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;padding-left:0px;"><font style="font-family:Arial Narrow;font-size:10pt;">•</font></div></td><td style="vertical-align:top;" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">AER consists of non-rate-regulated operations, including Genco, AERG, Marketing Company, and, through Genco, an </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">80%</font><font style="font-family:Arial Narrow;font-size:10pt;"> ownership interest in EEI, which Ameren consolidates for financial reporting purposes. On March 14, 2013, Ameren entered into a transaction agreement to divest New AER to IPH. See Note 16 - Divestiture Transactions and Discontinued Operations for additional information regarding the divestiture.</font></div></td></tr></table><div style="line-height:120%;padding-top:13px;text-indent:24px;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">Ameren has various other subsidiaries responsible for activities such as the provision of shared services.</font></div><div style="line-height:120%;padding-top:13px;text-align:left;text-indent:24px;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">In December 2012, Ameren determined that it intends to, and it is probable that it will, exit its Merchant Generation business before the end of the previously estimated useful lives of that business's long-lived assets. This determination resulted from Ameren’s analysis of the current and projected future financial condition of its Merchant Generation business segment, including the need to fund Genco debt maturities beginning in 2018, and its conclusion that this business segment is no longer a core component of its future business strategy. In consideration of this determination, Ameren has begun planning to reduce, and ultimately eliminate, the Merchant Generation business segment’s, including Genco's, reliance on Ameren’s financial support and shared services support. Furthermore, Ameren recorded a noncash long-lived asset impairment charge to reduce the carrying values of the Merchant Generation energy centers, except for the Joppa coal-fired energy center, to their estimated fair values. See Note 16 - Divestiture Transactions and Discontinued Operations. </font></div><div style="line-height:120%;padding-top:13px;text-indent:24px;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">On March 14, 2013, Ameren entered into a transaction agreement to divest New AER to IPH, which Ameren expects will occur in the fourth quarter of 2013. Immediately prior to Ameren's entry into the transaction agreement with IPH, on March 14, 2013, Genco exercised its option under the amended put option agreement with Medina Valley and received an initial payment of $</font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">100 million</font><font style="font-family:Arial Narrow;font-size:10pt;"> for the pending sale of its Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley, which was subject to FERC approval. On October 11, 2013, Ameren received FERC approval for the divestiture of New AER to IPH and Genco's sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley. Ameren expects a third-party sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers will be completed by the end of 2013. See Note 16 - Divestiture Transactions and Discontinued Operations for additional information regarding these divestitures. As a result of the transaction agreement with IPH and Ameren's plan to sell its Elgin, Gibson City, and Grand Tower gas-fired energy centers, Ameren determined that New AER and the Elgin, Gibson City, and Grand Tower gas-fired energy centers qualified for discontinued operations presentation beginning on March 14, 2013. Therefore, Ameren has segregated New AER's and the Elgin, Gibson City, and Grand Tower gas-fired energy centers' operating results, assets, and liabilities and presented them separately as discontinued operations for all periods presented in this report. Unless otherwise noted, these notes to the financial statements have been revised to exclude discontinued operations for all periods presented. All other information herein remains unchanged. The information contained herein does not modify or update the disclosures contained in Ameren's Annual Report on Form 10-K for the year ended December 31, 2012, filed with the SEC on March 1, 2013, in any way, nor does it reflect any subsequent information or events, other than as required to reflect the results of the discontinued operations presentation described above. Information presented for the Ameren Missouri and Ameren Illinois registrants also remains unchanged. See Note 16 - Divestiture Transactions and Discontinued Operations for additional information regarding that presentation.</font></div></div>
CY2010	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-804000000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-426000000	USD
CY2011	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1120000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-698000000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-426000000	USD
CY2011	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-1020000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1096000000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1310000000	USD
CY2011	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1048000000	USD
CY2011	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-949000000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-1153000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-1015000000	USD
CY2011	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1878000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1823000000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1690000000	USD
CY2011	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	1512000000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	1399000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	1403000000	USD
CY2010	us-gaap	Net Income Loss NetIncomeLoss	139000000	USD
CY2011	us-gaap	Net Income Loss NetIncomeLoss	519000000	USD
CY2012	us-gaap	Net Income Loss NetIncomeLoss	-974000000	USD
CY2011Q4	us-gaap	Net Income Loss NetIncomeLoss	25000000	USD
CY2012Q3	us-gaap	Net Income Loss NetIncomeLoss	374000000	USD
CY2011Q1	us-gaap	Net Income Loss NetIncomeLoss	71000000	USD
CY2012Q4	us-gaap	Net Income Loss NetIncomeLoss	-1156000000	USD
CY2011Q3	us-gaap	Net Income Loss NetIncomeLoss	285000000	USD
CY2011Q2	us-gaap	Net Income Loss NetIncomeLoss	138000000	USD
CY2012Q2	us-gaap	Net Income Loss NetIncomeLoss	211000000	USD
CY2012Q1	us-gaap	Net Income Loss NetIncomeLoss	-403000000	USD
CY2012	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	segment
CY2012	us-gaap	Operating Expenses OperatingExpenses	4590000000	USD
CY2011	us-gaap	Operating Expenses OperatingExpenses	5216000000	USD
CY2010	us-gaap	Operating Expenses OperatingExpenses	5144000000	USD
CY2010	us-gaap	Operating Income Loss OperatingIncomeLoss	1125000000	USD
CY2011	us-gaap	Operating Income Loss OperatingIncomeLoss	1011000000	USD
CY2012	us-gaap	Operating Income Loss OperatingIncomeLoss	1191000000	USD
CY2012Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	578000000	USD
CY2011Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	91000000	USD
CY2011Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	494000000	USD
CY2011Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	270000000	USD
CY2012Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	158000000	USD
CY2012Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	111000000	USD
CY2012Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	344000000	USD
CY2011Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	156000000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	138000000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	19000000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	14000000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	14000000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	14000000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	14000000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	63000000	USD
CY2012Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	200000000	USD
CY2011Q4	us-gaap	Other Assets Current OtherAssetsCurrent	151000000	USD
CY2012Q4	us-gaap	Other Assets Current OtherAssetsCurrent	98000000	USD
CY2012Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	667000000	USD
CY2011Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	760000000	USD
CY2010	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-10000000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	19000000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	8000000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-6000000	USD
CY2010	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	6000000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-14000000	USD
CY2012	us-gaap	Other Income OtherIncome	2000000	USD
CY2010	us-gaap	Other Income OtherIncome	4000000	USD
CY2011	us-gaap	Other Income OtherIncome	3000000	USD
CY2011	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	3000000	USD
CY2012	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	4000000	USD
CY2010	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	4000000	USD
CY2011Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	195000000	USD
CY2012Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	168000000	USD
CY2011Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	424000000	USD
CY2012Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	642000000	USD
CY2011	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	14000000	USD
CY2010	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-1000000	USD
CY2012	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	8000000	USD
CY2012	us-gaap	Other Noninterest Expense OtherNoninterestExpense	13000000	USD
CY2011	us-gaap	Other Noninterest Expense OtherNoninterestExpense	15000000	USD
CY2010	us-gaap	Other Noninterest Expense OtherNoninterestExpense	13000000	USD
CY2011	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	23000000	USD
CY2010	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	32000000	USD
CY2012	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	37000000	USD
CY2012	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	70000000	USD
CY2010	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	88000000	USD
CY2011	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	68000000	USD
CY2012	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	33000000	USD
CY2010	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	56000000	USD
CY2011	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	45000000	USD
CY2011Q4	us-gaap	Other Receivables Net Current OtherReceivablesNetCurrent	48000000	USD
CY2012Q4	us-gaap	Other Receivables Net Current OtherReceivablesNetCurrent	71000000	USD
CY2011	us-gaap	Payment Of Financing And Stock Issuance Costs PaymentOfFinancingAndStockIssuanceCosts		USD
CY2012	us-gaap	Payment Of Financing And Stock Issuance Costs PaymentOfFinancingAndStockIssuanceCosts	16000000	USD
CY2010	us-gaap	Payment Of Financing And Stock Issuance Costs PaymentOfFinancingAndStockIssuanceCosts	9000000	USD
CY2012	us-gaap	Payments For Nuclear Fuel PaymentsForNuclearFuel	91000000	USD
CY2011	us-gaap	Payments For Nuclear Fuel PaymentsForNuclearFuel	62000000	USD
CY2010	us-gaap	Payments For Nuclear Fuel PaymentsForNuclearFuel	68000000	USD
CY2012	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-2000000	USD
CY2010	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-2000000	USD
CY2011	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-12000000	USD
CY2012	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock		USD
CY2011	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock		USD
CY2010	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	52000000	USD
CY2012	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	382000000	USD
CY2010	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	368000000	USD
CY2011	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	375000000	USD
CY2011	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	6000000	USD
CY2010	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	8000000	USD
CY2012	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	6000000	USD
CY2012	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	403000000	USD
CY2011	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	220000000	USD
CY2010	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	271000000	USD
CY2011	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	881000000	USD
CY2010	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	941000000	USD
CY2012	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1063000000	USD
CY2011Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	1253000000	USD
CY2012Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	1138000000	USD
CY2012Q4	us-gaap	Preferred Stock Liquidation Preference PreferredStockLiquidationPreference	105.50
CY2012Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2012Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	100000000	shares
CY2012Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2012Q4	us-gaap	Preferred Stock Value PreferredStockValue	142000000	USD
CY2011Q4	us-gaap	Preferred Stock Value PreferredStockValue	142000000	USD
CY2012	us-gaap	Proceeds From Advances For Construction ProceedsFromAdvancesForConstruction	4000000	USD
CY2010	us-gaap	Proceeds From Advances For Construction ProceedsFromAdvancesForConstruction	29000000	USD
CY2011	us-gaap	Proceeds From Advances For Construction ProceedsFromAdvancesForConstruction	5000000	USD
CY2012	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock		USD
CY2010	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	80000000	USD
CY2011	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	65000000	USD
CY2012	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	882000000	USD
CY2010	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt		USD
CY2011	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt		USD
CY2010	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-221000000	USD
CY2011	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-481000000	USD
CY2012	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-148000000	USD
CY2012	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	384000000	USD
CY2011	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	199000000	USD
CY2010	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	256000000	USD
CY2012	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment		USD
CY2011	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	3000000	USD
CY2010	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	7000000	USD
CY2012	us-gaap	Profit Loss ProfitLoss	-974000000	USD
CY2010	us-gaap	Profit Loss ProfitLoss	151000000	USD
CY2011	us-gaap	Profit Loss ProfitLoss	526000000	USD
CY2011Q4	us-gaap	Profit Loss ProfitLoss	26000000	USD
CY2011Q3	us-gaap	Profit Loss ProfitLoss	287000000	USD
CY2011Q2	us-gaap	Profit Loss ProfitLoss	139000000	USD
CY2012Q4	us-gaap	Profit Loss ProfitLoss	-1155000000	USD
CY2012Q1	us-gaap	Profit Loss ProfitLoss	-403000000	USD
CY2011Q1	us-gaap	Profit Loss ProfitLoss	74000000	USD
CY2012Q3	us-gaap	Profit Loss ProfitLoss	374000000	USD
CY2012Q2	us-gaap	Profit Loss ProfitLoss	210000000	USD
CY2011Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	21849000000	USD
CY2012Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	22796000000	USD
CY2012Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	15348000000	USD
CY2011Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	14848000000	USD
CY2010	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	52000000	USD
CY2011	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	34000000	USD
CY2012	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	36000000	USD
CY2011Q4	us-gaap	Public Utilities Inventory PublicUtilitiesInventory	229000000	USD
CY2012Q4	us-gaap	Public Utilities Inventory PublicUtilitiesInventory	241000000	USD
CY2012Q4	us-gaap	Regulated Entity Other Assets Noncurrent RegulatedEntityOtherAssetsNoncurrent	3286000000	USD
CY2011Q4	us-gaap	Regulated Entity Other Assets Noncurrent RegulatedEntityOtherAssetsNoncurrent	3138000000	USD
CY2011Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	215000000	USD
CY2012Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	247000000	USD
CY2012Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1786000000	USD
CY2011Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1603000000	USD
CY2012Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	100000000	USD
CY2011Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	133000000	USD
CY2012Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	1589000000	USD
CY2011Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	1502000000	USD
CY2012	us-gaap	Repayments Of Other Long Term Debt RepaymentsOfOtherLongTermDebt	760000000	USD
CY2010	us-gaap	Repayments Of Other Long Term Debt RepaymentsOfOtherLongTermDebt	110000000	USD
CY2011	us-gaap	Repayments Of Other Long Term Debt RepaymentsOfOtherLongTermDebt	155000000	USD
CY2012Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1006000000	USD
CY2011Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2369000000	USD
CY2011	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	12000000	USD
CY2012	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	17000000	USD
CY2010	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	11000000	USD
CY2012	us-gaap	Revenues Revenues	5781000000	USD
CY2010	us-gaap	Revenues Revenues	6269000000	USD
CY2011	us-gaap	Revenues Revenues	6227000000	USD
CY2012Q2	us-gaap	Revenues Revenues	1402000000	USD
CY2011Q3	us-gaap	Revenues Revenues	1876000000	USD
CY2012Q4	us-gaap	Revenues Revenues	1258000000	USD
CY2011Q2	us-gaap	Revenues Revenues	1458000000	USD
CY2011Q4	us-gaap	Revenues Revenues	1296000000	USD
CY2011Q1	us-gaap	Revenues Revenues	1597000000	USD
CY2012Q1	us-gaap	Revenues Revenues	1412000000	USD
CY2012Q3	us-gaap	Revenues Revenues	1709000000	USD
CY2011	us-gaap	Share Based Compensation ShareBasedCompensation	17000000	USD
CY2012	us-gaap	Share Based Compensation ShareBasedCompensation	29000000	USD
CY2010	us-gaap	Share Based Compensation ShareBasedCompensation	15000000	USD
CY2012Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	4000000	shares
CY2011Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	148000000	USD
CY2012Q4	us-gaap	Short Term Borrowings ShortTermBorrowings		USD
CY2010	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	3000000	shares
CY2012	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues		shares
CY2011	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	2200000	shares
CY2011Q4	us-gaap	Stockholders Equity StockholdersEquity	7919000000	USD
CY2012Q4	us-gaap	Stockholders Equity StockholdersEquity	6616000000	USD
CY2012Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6767000000	USD
CY2011Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	8068000000	USD
CY2010Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7884000000	USD
CY2012Q4	us-gaap	Tax Credit Carryforward Amount TaxCreditCarryforwardAmount	109000000	USD
CY2011	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	434000000	USD
CY2012	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	443000000	USD
CY2010	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	424000000	USD
CY2011Q4	us-gaap	Taxes Payable Current TaxesPayableCurrent	53000000	USD
CY2012Q4	us-gaap	Taxes Payable Current TaxesPayableCurrent	50000000	USD
CY2011Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	285000000	USD
CY2012Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	291000000	USD
CY2010Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	246000000	USD
CY2009Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	135000000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	148000000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	156000000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	13000000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	125000000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	38000000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities		USD
CY2011	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	10000000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities		USD
CY2011	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	17000000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	77000000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	17000000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	22000000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	72000000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	5000000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	6000000	USD
CY2010Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	17000000	USD
CY2009Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	8000000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	5000000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	-9000000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	-1000000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	11000000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	2000000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	1000000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations		USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	1000000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	1000000	USD
CY2010Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate		USD
CY2012Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fifth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary	898000000	USD
CY2012Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	1563000000	USD
CY2012Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary	937000000	USD
CY2012Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	1434000000	USD
CY2012Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary	1122000000	USD
CY2012Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance Sheet Amount UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount	7613000000	USD
CY2012Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	1659000000	USD
CY2012	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	1514000000	USD
CY2010	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	1566000000	USD
CY2011	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	1580000000	USD
CY2012	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	242600000	shares
CY2010	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	238800000	shares
CY2011	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	241500000	shares
CY2012Q4	aee	Accumulated Depreciation Capital Lease AccumulatedDepreciationCapitalLease	52000000	USD
CY2011Q4	aee	Accumulated Depreciation Capital Lease AccumulatedDepreciationCapitalLease	52000000	USD
CY2012	aee	Actual Return In Excess Of Or Less Than Expected Return Percentage ActualReturnInExcessOfOrLessThanExpectedReturnPercentage	0.25
CY2012	aee	Aggregate Maximum Assessment Per Incident Under Price Andersen Liability Provisions Of Atomic Energy Act AggregateMaximumAssessmentPerIncidentUnderPriceAndersenLiabilityProvisionsOfAtomicEnergyAct	118000000	USD
CY2012	aee	Aggregate Nuclear Power Industry Insurance Policy Limit For Losses From Terrorist Attacks Within Twelve Month Period AggregateNuclearPowerIndustryInsurancePolicyLimitForLossesFromTerroristAttacksWithinTwelveMonthPeriod	3240000000	USD
CY2011	aee	Amount Gain Loss On Derivative Instruments That Qualify For Regulatory Deferral Net AmountGainLossOnDerivativeInstrumentsThatQualifyForRegulatoryDeferralNet	51000000	USD
CY2012	aee	Amount Gain Loss On Derivative Instruments That Qualify For Regulatory Deferral Net AmountGainLossOnDerivativeInstrumentsThatQualifyForRegulatoryDeferralNet	-112000000	USD
CY2012	aee	Amount Of Additional Weekly Indemnity Coverage Commencing After Initial Indemnity Coverage AmountOfAdditionalWeeklyIndemnityCoverageCommencingAfterInitialIndemnityCoverage	3600000	USD
CY2012	aee	Amount Of Coverage In Excess Of Primary Property Liability Coverage AmountOfCoverageInExcessOfPrimaryPropertyLiabilityCoverage	2250000000	USD
CY2012	aee	Amount Of Primary Property Liability Coverage AmountOfPrimaryPropertyLiabilityCoverage	500000000	USD
CY2012	aee	Amount Of Secondary Weekly Indemnity Coverage For Prolonged Nuclear Plant Outage In Excess Of Primary Indemnity Coverage AmountOfSecondaryWeeklyIndemnityCoverageForProlongedNuclearPlantOutageInExcessOfPrimaryIndemnityCoverage	900000	USD
CY2012	aee	Amount Of Weekly Indemnity Coverage Commencing Eight Weeks After Power Outage AmountOfWeeklyIndemnityCoverageCommencingEightWeeksAfterPowerOutage	4500000	USD
CY2012	aee	Amount Of Weekly Indemnity Coverage Thereafter Not Exceeding Policy Limit AmountOfWeeklyIndemnityCoverageThereafterNotExceedingPolicyLimit	490000000	USD
CY2012	aee	Annual Decommissioning Costs Included In Costs Of Service AnnualDecommissioningCostsIncludedInCostsOfService	7000000	USD
CY2011	aee	Annual Decommissioning Costs Included In Costs Of Service AnnualDecommissioningCostsIncludedInCostsOfService	7000000	USD
CY2010	aee	Annual Decommissioning Costs Included In Costs Of Service AnnualDecommissioningCostsIncludedInCostsOfService	7000000	USD
CY2012Q4	aee	Annual Obligation For Real Estate Leases And Railroad Licenses AnnualObligationForRealEstateLeasesAndRailroadLicenses	2000000	USD
CY2012Q4	aee	Capital And Operating Lease Obligations Due CapitalAndOperatingLeaseObligationsDue	442000000	USD
CY2012Q4	aee	Capital And Operating Lease Obligations Due Current CapitalAndOperatingLeaseObligationsDueCurrent	24000000	USD
CY2012Q4	aee	Capital And Operating Lease Obligations Due In Year Four CapitalAndOperatingLeaseObligationsDueInYearFour	20000000	USD
CY2012Q4	aee	Capital And Operating Lease Obligations Due In Year One CapitalAndOperatingLeaseObligationsDueInYearOne	19000000	USD
CY2012Q4	aee	Capital And Operating Lease Obligations Due In Year Three CapitalAndOperatingLeaseObligationsDueInYearThree	20000000	USD
CY2012Q4	aee	Capital And Operating Lease Obligations Due In Year Two CapitalAndOperatingLeaseObligationsDueInYearTwo	20000000	USD
CY2012Q4	aee	Capital And Operating Lease Obligations Due Thereafter CapitalAndOperatingLeaseObligationsDueThereafter	339000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Interest Included In Payments Current CapitalLeasesFutureMinimumPaymentsInterestIncludedInPaymentsCurrent	27000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Interest Included In Payments Due In Five Years CapitalLeasesFutureMinimumPaymentsInterestIncludedInPaymentsDueInFiveYears	27000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Interest Included In Payments Due In Four Years CapitalLeasesFutureMinimumPaymentsInterestIncludedInPaymentsDueInFourYears	27000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Interest Included In Payments Due In Three Years CapitalLeasesFutureMinimumPaymentsInterestIncludedInPaymentsDueInThreeYears	27000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Interest Included In Payments Due In Two Years CapitalLeasesFutureMinimumPaymentsInterestIncludedInPaymentsDueInTwoYears	27000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Interest Included In Payments Thereafter CapitalLeasesFutureMinimumPaymentsInterestIncludedInPaymentsThereafter	149000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments Current CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPaymentsCurrent	5000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments Due In Five Years CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPaymentsDueInFiveYears	6000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments Due In Four Years CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPaymentsDueInFourYears	6000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments Due In Three Years CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPaymentsDueInThreeYears	6000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments Due In Two Years CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPaymentsDueInTwoYears	5000000	USD
CY2012Q4	aee	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments Thereafter CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPaymentsThereafter	276000000	USD
CY2012	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxAttributableToNoncontrollingInterest	6000000	USD
CY2010	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxAttributableToNoncontrollingInterest	9000000	USD
CY2011	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxAttributableToNoncontrollingInterest	6000000	USD
CY2011	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	405000000	USD
CY2012	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	516000000	USD
CY2010	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	502000000	USD
CY2011	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Portion Attributable To Parent ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxPortionAttributableToParent	399000000	USD
CY2010	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Portion Attributable To Parent ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxPortionAttributableToParent	493000000	USD
CY2012	aee	Comprehensive Income Loss From Continuing Operations Net Of Tax Portion Attributable To Parent ComprehensiveIncomeLossFromContinuingOperationsNetOfTaxPortionAttributableToParent	510000000	USD
CY2012	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest	2000000	USD
CY2010	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest	1000000	USD
CY2011	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest	-5000000	USD
CY2010	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-357000000	USD
CY2012	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-1440000000	USD
CY2011	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	82000000	USD
CY2011	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Portion Attributable To Parent ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxPortionAttributableToParent	87000000	USD
CY2012	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Portion Attributable To Parent ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxPortionAttributableToParent	-1442000000	USD
CY2010	aee	Comprehensive Income Loss From Discontinued Operations Net Of Tax Portion Attributable To Parent ComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxPortionAttributableToParent	-358000000	USD
CY2012	aee	Debt Default Provision Excess DebtDefaultProvisionExcess	25000000	USD
CY2011Q4	aee	Deferred Tax Liabilities Intercompany Tax Gain Basis Step Up DeferredTaxLiabilitiesIntercompanyTaxGainBasisStepUp	54000000	USD
CY2012Q4	aee	Deferred Tax Liabilities Intercompany Tax Gain Basis Step Up DeferredTaxLiabilitiesIntercompanyTaxGainBasisStepUp	39000000	USD
CY2012Q4	aee	Defined Benefit Plan Estimated Future Employer Contributions Over Next Five Years DefinedBenefitPlanEstimatedFutureEmployerContributionsOverNextFiveYears	525000000	USD
CY2012	aee	Defined Benefit Plan Expected Return On Plan Assets Period DefinedBenefitPlanExpectedReturnOnPlanAssetsPeriod	P4Y
CY2012	aee	Defined Benefit Plan Future Amortization Of Prior Service Cost Credit Period DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCreditPeriod	P10Y
CY2012	aee	Defined Benefit Plan Number Of High Quality Bonds Used To Determine Yield Curve DefinedBenefitPlanNumberOfHighQualityBondsUsedToDetermineYieldCurve	600	bond
CY2012Q4	aee	Department Of Energy Investing Funding Support Number Of Small Modular Reactor Designs DepartmentOfEnergyInvestingFundingSupportNumberOfSmallModularReactorDesigns	2
CY2012Q4	aee	Department Of Energy Investing Funding Support Number Of Small Modular Reactor Designs Awarded DepartmentOfEnergyInvestingFundingSupportNumberOfSmallModularReactorDesignsAwarded	1
CY2012	aee	Department Of Energy Investing Funding Support Period DepartmentOfEnergyInvestingFundingSupportPeriod	P5Y
CY2011Q4	aee	Derivative Liabilities Current Carrying Amount DerivativeLiabilitiesCurrentCarryingAmount	122000000	USD
CY2012Q4	aee	Derivative Liabilities Current Carrying Amount DerivativeLiabilitiesCurrentCarryingAmount	92000000	USD
CY2011Q4	aee	Derivative Potential Loss DerivativePotentialLoss	150000000	USD
CY2012Q4	aee	Derivative Potential Loss DerivativePotentialLoss	15000000	USD
CY2012	aee	Disclosure Of Accrued Capital Expenditures Excluded From Statements Of Cash Flow DisclosureOfAccruedCapitalExpendituresExcludedFromStatementsOfCashFlow	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-left:4px;padding-top:13px;text-align:left;text-indent:24px;font-size:10pt;"><font style="font-family:Arial Narrow;font-size:10pt;">The following table provides accrued capital expenditures at </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">December 31, 2012</font><font style="font-family:Arial Narrow;font-size:10pt;">, </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">2011</font><font style="font-family:Arial Narrow;font-size:10pt;">, and </font><font style="font-family:Arial Narrow;font-size:10pt;color:#000000;text-decoration:none;">2010</font><font style="font-family:Arial Narrow;font-size:10pt;">, which represent noncash investing activity excluded from the statements of cash flows:</font></div><div style="line-height:100%;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;width:92.85714285714286%;border-collapse:collapse;text-align:left;"><tr><td colspan="4" rowspan="1"></td></tr><tr><td width="71%" rowspan="1" colspan="1"></td><td width="1%" rowspan="1" colspan="1"></td><td width="27%" rowspan="1" colspan="1"></td><td width="1%" rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:top;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:Arial Narrow;font-size:8pt;">2012</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:Arial Narrow;font-size:8pt;font-weight:bold;">$</font></div></td><td style="vertical-align:bottom;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;" rowspan="1" colspan="1"><div style="text-align:right;font-size:8pt;"><font style="font-family:Arial Narrow;font-size:8pt;font-weight:bold;">103</font></div></td><td style="vertical-align:bottom;border-top:1px solid #000000;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div></td></tr><tr><td style="vertical-align:top;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:Arial Narrow;font-size:8pt;">2011</font></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;" rowspan="1"><div style="text-align:right;font-size:8pt;"><font style="font-family:Arial Narrow;font-size:8pt;">92</font></div></td><td style="vertical-align:bottom;background-color:#cceeff;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div></td></tr><tr><td style="vertical-align:top;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:Arial Narrow;font-size:8pt;">2010</font></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;" rowspan="1"><div style="text-align:right;font-size:8pt;"><font style="font-family:Arial Narrow;font-size:8pt;">70</font></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div></td></tr></table></div></div></div>
CY2012Q4	aee	Disposal Group Including Discontinued Operation Accumulated Other Comprehensive Gain Loss DisposalGroupIncludingDiscontinuedOperationAccumulatedOtherComprehensiveGainLoss	19000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Accumulated Other Comprehensive Gain Loss DisposalGroupIncludingDiscontinuedOperationAccumulatedOtherComprehensiveGainLoss	-31000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Asset Retirement Obligations Current DisposalGroupIncludingDiscontinuedOperationAssetRetirementObligationsCurrent	64000000	USD
CY2012Q4	aee	Disposal Group Including Discontinued Operation Asset Retirement Obligations Current DisposalGroupIncludingDiscontinuedOperationAssetRetirementObligationsCurrent	78000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Derivative Assets Current DisposalGroupIncludingDiscontinuedOperationDerivativeAssetsCurrent	65000000	USD
CY2012Q4	aee	Disposal Group Including Discontinued Operation Derivative Assets Current DisposalGroupIncludingDiscontinuedOperationDerivativeAssetsCurrent	102000000	USD
CY2012Q4	aee	Disposal Group Including Discontinued Operation Derivative Liabilities Current DisposalGroupIncludingDiscontinuedOperationDerivativeLiabilitiesCurrent	63000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Derivative Liabilities Current DisposalGroupIncludingDiscontinuedOperationDerivativeLiabilitiesCurrent	39000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Long Term Debt Current DisposalGroupIncludingDiscontinuedOperationLongTermDebtCurrent	824000000	USD
CY2012Q4	aee	Disposal Group Including Discontinued Operation Long Term Debt Current DisposalGroupIncludingDiscontinuedOperationLongTermDebtCurrent	824000000	USD
CY2012Q4	aee	Disposal Group Including Discontinued Operation Noncontrolling Interest DisposalGroupIncludingDiscontinuedOperationNoncontrollingInterest	8000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Noncontrolling Interest DisposalGroupIncludingDiscontinuedOperationNoncontrollingInterest	7000000	USD
CY2011	aee	Disposal Group Including Discontinued Operation Other Income Loss DisposalGroupIncludingDiscontinuedOperationOtherIncomeLoss	1000000	USD
CY2010	aee	Disposal Group Including Discontinued Operation Other Income Loss DisposalGroupIncludingDiscontinuedOperationOtherIncomeLoss	2000000	USD
CY2012Q4	aee	Disposal Group Including Discontinued Operation Pension And Other Postretirement Benefit Current DisposalGroupIncludingDiscontinuedOperationPensionAndOtherPostretirementBenefitCurrent	40000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Pension And Other Postretirement Benefit Current DisposalGroupIncludingDiscontinuedOperationPensionAndOtherPostretirementBenefitCurrent	92000000	USD
CY2012Q4	aee	Disposal Group Including Discontinued Operation Property Plant And Equipment Net Current DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetCurrent	748000000	USD
CY2011Q4	aee	Disposal Group Including Discontinued Operation Property Plant And Equipment Net Current DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetCurrent	3279000000	USD
CY2011	aee	Donations Donations	8000000	USD
CY2010	aee	Donations Donations	19000000	USD
CY2012	aee	Donations Donations	24000000	USD
CY2012	aee	Estimated Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities EstimatedUnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	143000000	USD
CY2011	aee	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Transfers Net FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityTransfersNet	-19000000	USD
CY2012	aee	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Transfers Net FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityTransfersNet	182000000	USD
CY2012	aee	Generator Advances For Construction Refunded Net Of Receipts GeneratorAdvancesForConstructionRefundedNetOfReceipts		USD
CY2010	aee	Generator Advances For Construction Refunded Net Of Receipts GeneratorAdvancesForConstructionRefundedNetOfReceipts	-39000000	USD
CY2011	aee	Generator Advances For Construction Refunded Net Of Receipts GeneratorAdvancesForConstructionRefundedNetOfReceipts	-73000000	USD
CY2012Q4	aee	Insurance Aggregate Maximum Coverage InsuranceAggregateMaximumCoverage	12594000000	USD
CY2012Q4	aee	Insurance Maximum Coverage Per Incident InsuranceMaximumCoveragePerIncident	118000000	USD
CY2012Q4	aee	Letters Of Credit Held As Collateral LettersOfCreditHeldAsCollateral	1000000	USD
CY2011Q4	aee	Letters Of Credit Held As Collateral LettersOfCreditHeldAsCollateral	1000000	USD
CY2012	aee	Losses In Excess Of Primary Coverage LossesInExcessOfPrimaryCoverage	500000000	USD
CY2012	aee	Maximum Annual Payment In Calendar Year Per Reactor Incident Under Price Andersen Liability Provisions Of Atomic Energy Act MaximumAnnualPaymentInCalendarYearPerReactorIncidentUnderPriceAndersenLiabilityProvisionsOfAtomicEnergyAct	17500000	USD
CY2012	aee	Maximum Annual Payment Per Incident At Licensed Commercia Lnuclear Reactor MaximumAnnualPaymentPerIncidentAtLicensedCommerciaLnuclearReactor	17500000	USD
CY2012	aee	Missouri Public Service Commission Requirement To File Updated Cost Study And Funding Analysis For Decommissioning Energy Center Period MissouriPublicServiceCommissionRequirementToFileUpdatedCostStudyAndFundingAnalysisForDecommissioningEnergyCenterPeriod	P3Y
CY2012	aee	Number Of Additional Weeks After Initial Indemnity Coverage For Power Outage NumberOfAdditionalWeeksAfterInitialIndemnityCoverageForPowerOutage	P5Y11M
CY2012Q4	aee	Number Of Combustion Turbine Electric Generation Equipment Under Capital Lease Agreements NumberOfCombustionTurbineElectricGenerationEquipmentUnderCapitalLeaseAgreements	2	equipment
CY2011Q4	aee	Number Of Combustion Turbine Electric Generation Equipment Under Capital Lease Agreements NumberOfCombustionTurbineElectricGenerationEquipmentUnderCapitalLeaseAgreements	2	equipment
CY2012	aee	Number Of States Participating In Cap And Trade Program NumberOfStatesParticipatingInCapAndTradeProgram	28	state
CY2012	aee	Number Of Years Limit Of Liability And Maximum Potential Annual Payments Are Adjusted NumberOfYearsLimitOfLiabilityAndMaximumPotentialAnnualPaymentsAreAdjusted	P5Y
CY2012	aee	Numberofweeksofcoverageafterthefirsteightweeksofanoutage Numberofweeksofcoverageafterthefirsteightweeksofanoutage	P1Y
CY2012	aee	Nwf Fee Number Of Mills NwfFeeNumberOfMills	1	mill
CY2011	aee	Other Comprehensive Income Loss From Discontinued Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-20000000	USD
CY2012	aee	Other Comprehensive Income Loss From Discontinued Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	58000000	USD
CY2010	aee	Other Comprehensive Income Loss From Discontinued Operations Net Of Tax Including Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossFromDiscontinuedOperationsNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-16000000	USD
CY2011	aee	Payment Of Accrued Interest PaymentOfAccruedInterest	1000000	USD
CY2012	aee	Payment Of Accrued Interest PaymentOfAccruedInterest		USD
CY2010	aee	Payment Of Accrued Interest PaymentOfAccruedInterest		USD
CY2012	aee	Percent Of Top Performing Facilities PercentOfTopPerformingFacilities	0.12
CY2011	aee	Premium Related To Debt Redemptions PremiumRelatedToDebtRedemptions		USD
CY2012	aee	Premium Related To Debt Redemptions PremiumRelatedToDebtRedemptions	-138000000	USD
CY2010	aee	Premium Related To Debt Redemptions PremiumRelatedToDebtRedemptions		USD
CY2012Q4	aee	Property Plant And Equipment Net Before Construction Work In Progress PropertyPlantAndEquipmentNetBeforeConstructionWorkInProgress	14450000000	USD
CY2011Q4	aee	Property Plant And Equipment Net Before Construction Work In Progress PropertyPlantAndEquipmentNetBeforeConstructionWorkInProgress	13981000000	USD
CY2012Q4	aee	Property Plant And Equipment Number Of Capital Lease Agreements PropertyPlantAndEquipmentNumberOfCapitalLeaseAgreements	2
CY2011Q4	aee	Property Plant And Equipment Number Of Capital Lease Agreements PropertyPlantAndEquipmentNumberOfCapitalLeaseAgreements	2
CY2012Q4	aee	Receivables Payables And Accrued Income Net ReceivablesPayablesAndAccruedIncomeNet	2000000	USD
CY2011Q4	aee	Receivables Payables And Accrued Income Net ReceivablesPayablesAndAccruedIncomeNet	-1000000	USD
CY2012Q4	aee	Related Party Transaction Guarantees Outstanding RelatedPartyTransactionGuaranteesOutstanding	354000000	USD
CY2012	aee	Tax Credit Carryforward Change In Valuation Allowance TaxCreditCarryforwardChangeInValuationAllowance	1000000	USD
CY2011	aee	Tax Grants Received Related To Renewable Energy Properties TaxGrantsReceivedRelatedToRenewableEnergyProperties		USD
CY2010	aee	Tax Grants Received Related To Renewable Energy Properties TaxGrantsReceivedRelatedToRenewableEnergyProperties		USD
CY2012	aee	Tax Grants Received Related To Renewable Energy Properties TaxGrantsReceivedRelatedToRenewableEnergyProperties	18000000	USD
CY2012	aee	Transfers Into Assets And Liabilities Classified As Fair Value Inputs Level3 And Transfers Out Of Assets And Liabilities Classified As Fair Value Inputs Level2 TransfersIntoAssetsAndLiabilitiesClassifiedAsFairValueInputsLevel3AndTransfersOutOfAssetsAndLiabilitiesClassifiedAsFairValueInputsLevel2		USD
CY2012	dei	Amendment Flag AmendmentFlag	false
CY2012	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2012	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2012	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2012
CY2012	dei	Document Period End Date DocumentPeriodEndDate	2012-12-31
CY2012	dei	Document Type DocumentType	8-K
CY2012	dei	Entity Central Index Key EntityCentralIndexKey	0001002910
CY2013Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	242634671	shares
CY2012	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2012	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2012Q2	dei	Entity Public Float EntityPublicFloat	8137966865	USD
CY2012	dei	Entity Registrant Name EntityRegistrantName	AMEREN CORP
CY2012	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2012	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2012	dei	Trading Symbol TradingSymbol	AEE

Files In Submission

Name	View Source	Status
0001002910-13-000092-index-headers.html	Edgar Link	pending
0001002910-13-000092-index.html	Edgar Link	pending
0001002910-13-000092.txt	Edgar Link	pending
0001002910-13-000092-xbrl.zip	Edgar Link	pending
a8-kregistrationfiling.htm	Edgar Link	pending
aee-20131017.xml	Edgar Link	completed
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aee-20131017_cal.xml	Edgar Link	unprocessable
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$AEE
AMEREN CORP Stock $aee

2011 Q4 Form 8-K Financial Statement

#000100291013000092 Filed on October 17, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AEE AMEREN CORP Stock $aee

2011 Q4 Form 8-K Financial Statement

#000100291013000092 Filed on October 17, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AEE
AMEREN CORP Stock $aee