2.4.0.8040075 - Disclosure - Commitments and Contingencies (Details-2)truefalsefalse1false USDfalsefalse$FROM_Jan01_2013_TO_Jun30_2013http://www.sec.gov/CIK0001161728duration2013-01-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 2mgee_ChattelPaperPurchaseAgreementAbstractmgee_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Chattel Paper Purchase Agreement [Abstract]2false 3mgee_ChattelPaperPurchaseAgreementMaximumInterestmgee_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse1000000010000000USD$falsetruefalsexbrli:monetaryItemTypemonetaryMGE is party to a chattel paper purchase agreement with a financial institution under which it can sell or finance an undivided interest with recourse, in up to $10.0 million of the financing program receivables, until August 31, 2011.No definition available.false2Chattel paper purchase agreement maximum interest3false 3mgee_OutstandingInterestInChattelPaperReceivablesmgee_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse44000004400000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryOutstanding interest in chattel paper interest receivables.No definition available.false2Outstanding interest in chattel paper receivables4false 3us-gaap_ServicingAssetAtAmortizedValueus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse200000200000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmortized carrying amount (balance) as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7524895&loc=d3e120260-111741 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122739-111746 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 140 -Paragraph 13A, 13B -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS140-4/FIN46(R)-8 -Paragraph B10 -Subparagraph a(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 140 -Paragraph 17 -Subparagraph g(1)(a) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.No definition available.false2Purchase obligation due in next twelve months32false 5us-gaap_PurchaseObligationDueInSecondYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse4859300048593000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryMinimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.No definition available.false2Purchase obligation due in second year33false 5us-gaap_PurchaseObligationDueInThirdYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse4766700047667000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryMinimum amount of purchase arrangement maturing in the third fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.No definition available.false2Purchase obligation due in third year34false 5us-gaap_PurchaseObligationDueInFourthYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse4869700048697000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryMinimum amount of purchase arrangement maturing in the fourth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.No definition available.false2Purchase obligation due in fourth year35false 5us-gaap_PurchaseObligationDueInFifthYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse4971700049717000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryMinimum amount of purchase arrangement maturing in the fifth fiscal year following the latest fiscal year. 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Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.No definition available.false2Purchase obligation due in fourth year42false 5us-gaap_PurchaseObligationDueInFifthYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryMinimum amount of purchase arrangement maturing in the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.No definition available.false2Purchase obligation due in fifth year43false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse6false USDtruefalse$AS_OF_Jun30_2013_us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis_Commitments2Memberhttp://www.sec.gov/CIK0001161728instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseSmart Grid Investment Grant [Member]us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxisxbrldihttp://xbrl.org/2006/xbrldimgee_Commitments2Memberus-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Smart Grid Investment Grant [Member]44true 4us-gaap_ContractualObligationFiscalYearMaturityAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Contractual obligation [Abstract]45false 5us-gaap_ContractualObligationDueInNextTwelveMonthsus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse14000001400000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of contractual obligation maturing in the next fiscal year following the latest fiscal year.No definition available.false2Contractual obligation due in next twelve months46false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse7false USDtruefalse$AS_OF_Jun30_2013_us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis_PaymentGuaranteeMemberhttp://www.sec.gov/CIK0001161728instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseChattel Paper [Member]us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PaymentGuaranteeMemberus-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Chattel Paper [Member]47true 4us-gaap_ContractualObligationFiscalYearMaturityAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Contractual obligation [Abstract]48false 5us-gaap_ContractualObligationDueInNextTwelveMonthsus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse372000372000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of contractual obligation maturing in the next fiscal year following the latest fiscal year.No definition available.false2Contractual obligation due in next twelve months49false 5us-gaap_ContractualObligationDueInSecondYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse577000577000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of contractual obligation maturing in the second fiscal year following the latest fiscal year.No definition available.false2Contractual obligation due in second year50false 5us-gaap_ContractualObligationDueInThirdYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse891000891000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of contractual obligation maturing in the third fiscal year following the latest fiscal year.No definition available.false2Contractual obligation due in third year51false 5us-gaap_ContractualObligationDueInFourthYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse815000815000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of contractual obligation maturing in the fourth fiscal year following the latest fiscal year.No definition available.false2Contractual obligation due in fourth year52false 5us-gaap_ContractualObligationDueInFifthYearus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse405000405000USD$falsetruefalsexbrli:monetaryItemTypemonetaryAmount of contractual obligation maturing in the fifth fiscal year following the latest fiscal year.No definition available.false2Contractual obligation due in fifth yearfalseCommitments and Contingencies (Details-2) (USD $)NoRoundingUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.mgeenergy.com/role/DisclosureCommitmentsAndContingenciesDetails2152