2.4.0.8010120 - Disclosure - Investment in ATCtruefalsefalse1false falsefalseFROM_Jan01_2013_TO_Jun30_2013http://www.sec.gov/CIK0001161728duration2013-01-01T00:00:002013-06-30T00:00:001true 1mgee_InvestmentInAtcDisclosureAbstractmgee_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Investment in ATC Disclosure [Abstract]2false 2us-gaap_EquityMethodInvestmentsDisclosureTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse003.       Investment in ATC - MGE Energy and MGE. ATC owns and operates electric transmission facilities primarily in Wisconsin. MGE received an interest in ATC when it, like other Wisconsin electric utilities, contributed its electric transmission facilities to ATC. That interest is presently held by MGE Transco, which is jointly owned by MGE Energy and MGE. MGE Transco has accounted for its investment in ATC under the equity method of accounting. For the six months ended June 30, 2013 and 2012, MGE Transco recorded equity earnings from the investment in ATC of $4.7 million and $4.5 million, respectively. Dividends received from ATC were $3.6 million and $3.5 million for the six months ended June 30, 2013 and 2012, respectively. In addition, during the six months ended June 30, 2013 and 2012, MGE Transco made $0.7 million and $0.9 million in capital contributions to ATC, respectively. On July 31, 2013, MGE Transco made a $0.4 million capital contribution to ATC. MGE Transco's investment in ATC as of June 30, 2013 and December 31, 2012 was $62.8 million and $61.0 million, respectively. At June 30, 2013, MGE is the majority owner, and MGE Energy, the holding company, is the minority owner of MGE Transco. MGE Energy's proportionate share of the equity and net income of MGE Transco is classified within the MGE financial statements as noncontrolling interest.  ATC's summarized financial data for the three and six months ended June 30, 2013 and 2012, is as follows: <div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="3" style="width: 158px; text-align:center;border-color:#000000;min-width:158px;">Three Months Ended</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="3" style="width: 158px; text-align:center;border-color:#000000;min-width:158px;">Six Months Ended</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="3" style="width: 158px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:158px;">June 30,</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="3" style="width: 158px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:158px;">June 30,</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;">(In thousands)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">2013</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">2012</td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">2013</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">2012</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;">Operating revenues</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:74px;">152,128</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:74px;">152,171</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:74px;">303,865</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:74px;">299,833</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;">Operating expenses</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">(69,875)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">(71,760)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">(139,645)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">(141,326)</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;">Other income (expense), net</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">116</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">(327)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">(332)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; text-align:right;border-color:#000000;min-width:74px;">(827)</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;">Interest expense, net</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:74px;">(21,052)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:74px;">(20,776)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:74px;">(42,096)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:74px;">(40,277)</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr><tr style="height: 15px"><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td><td style="width: 245px; text-align:left;border-color:#000000;min-width:245px;">Earnings before members' income taxes</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:74px;">61,317</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:74px;">59,308</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:74px;">121,792</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 74px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:74px;">117,403</td><td style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"> </td></tr></table></div>falsefalsefalsenonnum:textBlockItemTypenaThe entire disclosure for equity method investments and joint ventures. Equity method investments are investments that give the investor the ability to exercise significant influence over the operating and financial policies of an investee. Joint ventures are entities owned and operated by a small group of businesses as a separate and specific business or project for the mutual benefit of the members of the group.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32847-111569 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32787-111569 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 20 -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. false0Investment in ATCfalseInvestment in ATCUnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.mgeenergy.com/role/DisclosureInvestmentInATC12