1.0.0.3 false Statement of Financial Position, Classified (USD $) In Millions, except Share data false 1 $ false true false Unaudited false Unaudited scenarioName asi http://www.firstenergycorp.com/20090507 u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Standard http://www.xbrl.org/2003/instance shares xbrli 0 false 2 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Standard http://www.xbrl.org/2003/instance shares xbrli 0 8 6 us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 9 7 us-gaap_CashAndCashEquivalentsAtCarryingValue us-gaap true debit instant monetary Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of... false false false false false false false false false 1 true true 399000000 399 false true 2 true true 545000000 545 false false Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 26 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Subparagraph fn1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 true 12 7 us-gaap_AccountsReceivableNetCurrentAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 13 8 us-gaap_AccountsReceivableNetCurrent us-gaap true debit instant monetary Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is... false false false false false false false false false 1 false true 1266000000 1266 false true 2 false true 1304000000 1304 false false Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Subparagraph a(1) -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 4 -Article 5 true 14 7 us-gaap_OtherReceivables us-gaap true debit instant monetary Carrying amounts due as of the balance sheet date from parties or arising from transactions not otherwise specified in the... false false false false false false false false false 1 false true 159000000 159 false true 2 false true 167000000 167 false false Carrying amounts due as of the balance sheet date from parties or arising from transactions not otherwise specified in the taxonomy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer. For unclassified balance sheets, represents the entire amount receivable. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 8 -Article 5 false 15 5 us-gaap_InventoryNetAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 16 6 us-gaap_InventoryNet us-gaap true debit instant monetary Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other... false false false false false false false false false 1 false true 657000000 657 false true 2 false true 605000000 605 false false Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer). No authoritative reference available. true 17 5 us-gaap_PrepaidExpenseCurrentAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 18 6 us-gaap_PrepaidTaxes us-gaap true debit instant monetary Carrying amount as of the balance sheet date of payments made in advance for income and other taxes, which will be charged... false false false false false false false false false 1 false true 318000000 318 false true 2 false true 283000000 283 false false Carrying amount as of the balance sheet date of payments made in advance for income and other taxes, which will be charged against earnings within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 3 -Section A -Paragraph 4 false 19 5 us-gaap_OtherAssetsCurrent us-gaap true debit instant monetary Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet due... false false false false false false false false false 1 false true 205000000 205 false true 2 false true 149000000 149 false false Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet due to materiality considerations. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 8 -Article 5 false 20 5 us-gaap_AssetsCurrent us-gaap true debit instant monetary Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or... false false false false false false false false false 1 false true 3004000000 3004 false true 2 false true 3053000000 3053 false false Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 9 -Article 5 true 23 6 us-gaap_PropertyPlantAndEquipmentGrossAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 24 7 us-gaap_PropertyPlantAndEquipmentGross us-gaap true debit instant monetary Carrying amount at the balance sheet date for long-lived physical assets used in the normal conduct of business and not... false false false false false false false false false 1 false true 26757000000 26757 false true 2 false true 26482000000 26482 false false Carrying amount at the balance sheet date for long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, physical structures, machinery, vehicles, furniture, computer equipment, construction in progress, and similar items. Amount does not include depreciation. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 4, 5 true 25 6 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment us-gaap true credit instant monetary The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not... false false false false false false false false false 1 false true 10947000000 10947 false true 2 false true 10821000000 10821 false false The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -Subparagraph c Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 14 -Article 5 false 26 6 fe_NetPlantExcludingCWIP fe false debit instant monetary Period end amount of total net PPE false false false false false false false false false 1 false true 15810000000 15810 false true 2 false true 15661000000 15661 false false Period end amount of total net PPE No authoritative reference available. false 27 6 us-gaap_ConstructionInProgressGross us-gaap true debit instant monetary Carrying amount at the balance sheet date of long-lived asset under construction that include construction costs to date on... false false false false false false false false false 1 false true 2397000000 2397 false true 2 false true 2062000000 2062 false false Carrying amount at the balance sheet date of long-lived asset under construction that include construction costs to date on capital projects that have not been completed and assets being constructed that are not ready to be placed into service. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 4, 5 false 28 6 us-gaap_PropertyPlantAndEquipmentNet us-gaap true debit instant monetary Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others,... false false false false false false false false false 1 false true 18207000000 18207 false true 2 false true 17723000000 17723 false false Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, and production equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 12 -Paragraph 5 -Subparagraph b, c true 30 6 us-gaap_LongTermInvestmentsAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 31 7 us-gaap_DecommissioningFundInvestments us-gaap true debit instant monetary Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues... false false false false false false false false false 1 false true 1649000000 1649 false true 2 false true 1708000000 1708 false false Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 12 -Article 5 false 32 7 us-gaap_MarketableSecuritiesNoncurrentAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 33 8 us-gaap_HeldToMaturitySecuritiesNoncurrent us-gaap true debit instant monetary This item represents investments in debt securities which are categorized as held-to-maturity and that have scheduled... false false false false false false false false false 1 false true 561000000 561 false true 2 false true 598000000 598 false false This item represents investments in debt securities which are categorized as held-to-maturity and that have scheduled maturities more than one year from the balance sheet date or operating cycle, if longer; such investments are measured at amortized cost (carrying value). The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 17 false 34 7 us-gaap_OtherLongTermInvestments us-gaap true debit instant monetary Other noncurrent investments not otherwise specified in the taxonomy, not including investments in marketable securities. false false false false false false false false false 1 false true 689000000 689 false true 2 false true 711000000 711 false false Other noncurrent investments not otherwise specified in the taxonomy, not including investments in marketable securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 12 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph (a) -Subparagraph 1(f) -Article 7 false 35 7 us-gaap_LongTermInvestments us-gaap true debit instant monetary Noncurrent investments, not including marketable securities. false false false false false false false false false 1 false true 2899000000 2899 false true 2 false true 3017000000 3017 false false Noncurrent investments, not including marketable securities. No authoritative reference available. true 36 5 us-gaap_Goodwill us-gaap true debit instant monetary Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized... false false false false false false false false false 1 false true 5575000000 5575 false true 2 false true 5575000000 5575 false false Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of SFAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 43 false 37 5 us-gaap_RegulatoryAssetsNoncurrent us-gaap true debit instant monetary Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered... false false false false false false false false false 1 false true 2938000000 2938 false true 2 false true 3140000000 3140 false false Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 71 -Paragraph 9, 10 false 38 5 us-gaap_DerivativeInstrumentsAndHedgesNoncurrentAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 39 6 us-gaap_CommodityContractAssetNoncurrent us-gaap true debit instant monetary Carrying amount as of the balance sheet date of the asset arising from commodity contracts such as futures contracts tied to... false false false false false false false false false 1 false true 340000000 340 false true 2 false true 434000000 434 false false Carrying amount as of the balance sheet date of the asset arising from commodity contracts such as futures contracts tied to the movement of a particular commodity, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer. No authoritative reference available. false 40 5 us-gaap_OtherAssetsNoncurrent us-gaap true debit instant monetary Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet... false false false false false false false false false 1 false true 594000000 594 false true 2 false true 579000000 579 false false Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet due to materiality considerations. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 false 41 5 us-gaap_AssetsNoncurrent us-gaap true debit instant monetary Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or... false false false false false false false false false 1 false true 9447000000 9447 false true 2 false true 9728000000 9728 false false Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 true 42 4 us-gaap_Assets us-gaap true debit instant monetary Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future... false false false false false false false false false 1 false true 33557000000 33557 false true 2 false true 33521000000 33521 false false Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 true 47 7 us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrentAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 48 8 us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent us-gaap true credit instant monetary Obligation related to long-term debt (excluding convertible debt) and capital leases, the portion which is due in one year or... false false false false false false false false false 1 false true 2144000000 2144 false true 2 false true 2476000000 2476 false false Obligation related to long-term debt (excluding convertible debt) and capital leases, the portion which is due in one year or less in the future. No authoritative reference available. true 49 7 us-gaap_ShortTermBorrowingsAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 50 8 us-gaap_ShortTermBorrowings us-gaap true credit instant monetary Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal... false false false false false false false false false 1 false true 2397000000 2397 false true 2 false true 2397000000 2397 false false Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph (a) -Subparagraph 16(a)1 -Article 7 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph 2, 3 -Article 9 true 51 6 us-gaap_AccountsPayableAndAccruedLiabilitiesAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 52 7 us-gaap_AccountsPayable us-gaap true credit instant monetary Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and... false false false false false false false false false 1 false true 704000000 704 false true 2 false true 794000000 794 false false Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. For classified balance sheets, used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer); for unclassified balance sheets, used to reflect the total liabilities (regardless of due date). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 false 53 7 us-gaap_TaxesPayableAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 54 8 us-gaap_TaxesPayable us-gaap true credit instant monetary Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll,... false false false false false false false false false 1 false true 281000000 281 false true 2 false true 333000000 333 false false Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. For classified balance sheets, used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer); for unclassified balance sheets, used to reflect the total liabilities (regardless of due date). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 true 55 6 us-gaap_OtherLiabilitiesCurrent us-gaap true credit instant monetary Aggregate carrying amount, as of the balance sheet date, of current obligations not separately disclosed in the balance sheet... false false false false false false false false false 1 false true 1169000000 1169 false true 2 false true 1098000000 1098 false false Aggregate carrying amount, as of the balance sheet date, of current obligations not separately disclosed in the balance sheet due to materiality considerations. Current liabilities are expected to be paid within one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Chapter -Section 02 -Paragraph 20 -Article 5 false 56 5 us-gaap_Liabilities us-gaap true credit instant monetary Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable... false false false false false false false false false 1 false true 6695000000 6695 false true 2 false true 7098000000 7098 false false Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future. No authoritative reference available. true 59 6 us-gaap_StockholdersEquityAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 60 7 us-gaap_CommonStockValue us-gaap true credit instant monetary Value of issued common stock that may be calculated differently depending on whether the stock is issued at par value, no par... false false false false false false false false false 1 false true 31000000 31 false true 2 false true 31000000 31 false false Value of issued common stock that may be calculated differently depending on whether the stock is issued at par value, no par or stated value. Note: elements for number of common shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Article 5 false 61 7 us-gaap_AdditionalPaidInCapitalAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 62 8 us-gaap_AdditionalPaidInCapital us-gaap true credit instant monetary Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions... false false false false false false false false false 1 false true 5459000000 5459 false true 2 false true 5473000000 5473 false false Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of APIC associated with common AND preferred stock. For APIC associated with only common stock, use the element Additional Paid In Capital, Common Stock. For APIC associated with only preferred stock, use the element Additional Paid In Capital, Preferred Stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 98-5 -Paragraph 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 62, 63 true 63 7 us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 64 8 us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap true credit instant monetary Accumulated change in equity from transactions and other events and circumstances from nonowner sources, net of tax effect,... false false false false false false false false false 1 false true -1350000000 -1350 false true 2 false true -1380000000 -1380 false false Accumulated change in equity from transactions and other events and circumstances from nonowner sources, net of tax effect, at fiscal year-end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, and unrealized gains and losses on certain investments in debt and equity securities as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 14, 17, 26 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 true 65 7 us-gaap_RetainedEarningsAccumulatedDeficitAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 66 8 us-gaap_RetainedEarningsAccumulatedDeficit us-gaap true credit instant monetary The cumulative amount of the reporting entity's undistributed earnings or deficit. false false false false false false false false false 1 false true 4110000000 4110 false true 2 false true 4159000000 4159 false false The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 true 67 7 us-gaap_StockholdersEquity us-gaap true credit instant monetary Total of all Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the... false false false false false false false false false 1 false true 8250000000 8250 false true 2 false true 8283000000 8283 false false Total of all Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity. This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section E Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 true 68 6 us-gaap_MinorityInterest us-gaap true credit instant monetary Carrying amount of the equity interests owned by noncontrolling shareholders, partners, or other equity holders in one or... false false false false false false false false false 1 false true 34000000 34 false true 2 false true 32000000 32 false false Carrying amount of the equity interests owned by noncontrolling shareholders, partners, or other equity holders in one or more of the entities included in the reporting entity's consolidated financial statements. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 27 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph (a) -Subparagraph 20 -Article 7 false 69 6 fe_TotalEquity fe false na instant monetary The sum of Total Common Stockholders Equity and Noncontrolling Interest false false false false false false false false false 1 false true 8284000000 8284 false true 2 false true 8315000000 8315 false false The sum of Total Common Stockholders Equity and Noncontrolling Interest No authoritative reference available. false 70 5 us-gaap_LongTermDebtAndCapitalLeaseObligations us-gaap true credit instant monetary Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due... false false false false false false false false false 1 false true 9697000000 9697 false true 2 false true 9100000000 9100 false false Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date. 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No authoritative reference available. false 72 4 us-gaap_LiabilitiesNoncurrentAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false true 2 false false 0 0 false false No definition available. false 73 5 us-gaap_DeferredTaxLiabilitiesNoncurrent us-gaap true credit instant monetary Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net... false false false false false false false false false 1 false true 2130000000 2130 false true 2 false true 2163000000 2163 false false Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A noncurrent taxable temporary difference is a difference between the tax basis and the carrying amount of a noncurrent asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference. 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An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 143 -Paragraph 3, 10, 22 true 76 5 us-gaap_SaleLeasebackTransactionDeferredGainNet us-gaap true credit instant monetary The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts... false false false false false false false false false 1 false true 1018000000 1018 false true 2 false true 1027000000 1027 false false The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period. 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For unclassified balance sheets, this represents the entire liability recognized in the balance sheet that is associated with the defined benefit plans. 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