Rate Matters	9 Months Ended
Sep. 30, 2011
Rate Matters Disclosure [Abstract]
Rate Matters	12. Rate Matters - MGE Energy and MGE. a. Rate Proceedings. In May 2011, MGE filed with the PSCW a limited scope reopener of its 2012 electric and gas rates. The reopener included an update to MGE's electric fuel and purchased power costs, increased transmission costs, an update to the Elm Road costs, and an increase for energy efficiency programs. The requested changes would result in a 5.7% increase in electric rates and a 0.4% increase in gas rates effective January 1, 2012. MGE has also requested a deferral of CSAPR costs. On January 12, 2011, the PSCW authorized MGE to increase 2011 rates for retail electric customers by 2.3% or $8.0 million and to increase gas rates by 1.0% or $1.9 million. The increase in retail electric rates is driven by costs for MGE's share of the Elm Road Units. Pursuant to the provisions of this rate order, the fuel rules bandwidth effective January 1, 2011, will be plus or minus 2%. See below for further description of fuel rules. Authorized return on common stock equity was set at 10.3% based on a 58.1% utility common equity. In December 2009, the PSCW authorized MGE to increase 2010 rates for retail electric customers by 3.3% or $11.9 million, while gas rates decreased 0.74% or $1.5 million. The increase in retail electric rates was driven by costs for MGE's share of the Elm Road Units and transmission reliability enhancements. Pursuant to the provisions of this rate order, the fuel rules bandwidth effective January 1, 2010, was plus or minus 2%. Authorized return on common stock equity was set at 10.4% based on a 55.3% utility common equity. b. Fuel Rules. The PSCW approved new fuel rules that became effective January 1, 2011. The new rules require the PSCW and Wisconsin utilities to automatically defer electric fuel-related costs that fall outside a symmetrical cost tolerance band. Any over/under recovery of the deferred costs is determined on an annual basis and will be adjusted in future billings to its electric retail customers. Under fuel rules, MGE would defer costs, less any excess revenues, if its actual electric fuel costs exceeded 102% of the electric fuel costs allowed in its latest rate order. Excess revenues are defined as revenues in the plan year that provide MGE with a greater return on common equity than authorized by the PSCW in MGE's latest rate order. Conversely, MGE is required to defer the benefit of lower costs if actual electric fuel costs were less than 98% of the electric fuel costs allowed in that order. As of September 30, 2011, MGE did not defer any electric fuel-related costs. In 2010, a refund of $0.3 million of over collected 2009 fuel costs was refunded on customers' April 2010 bills. c. Purchased Gas Adjustment Clause. MGE's natural gas rates are subject to a fuel adjustment clause designed to recover or refund the difference between the actual cost of purchased gas and the amount included in rates. Differences between the amounts billed to customers and the actual costs recoverable are deferred and recovered or refunded in future periods by means of prospective monthly adjustments to rates. At September 30, 2011 and December 31, 2010, MGE had over collected $1.1 million and $4.8 million, respectively. These amounts were recorded in other current liabilities on the consolidated balance sheet.

Rate Matters

9 Months Ended

Sep. 30, 2011

12. Rate Matters - MGE Energy and MGE.

a. Rate Proceedings.

In May 2011, MGE filed with the PSCW a limited scope reopener of its 2012 electric and gas rates. The reopener included an update to MGE's electric fuel and purchased power costs, increased transmission costs, an update to the Elm Road costs, and an increase for energy efficiency programs. The requested changes would result in a 5.7% increase in electric rates and a 0.4% increase in gas rates effective January 1, 2012. MGE has also requested a deferral of CSAPR costs.

On January 12, 2011, the PSCW authorized MGE to increase 2011 rates for retail electric customers by 2.3% or $8.0 million and to increase gas rates by 1.0% or $1.9 million. The increase in retail electric rates is driven by costs for MGE's share of the Elm Road Units. Pursuant to the provisions of this rate order, the fuel rules bandwidth effective January 1, 2011, will be plus or minus 2%. See below for further description of fuel rules. Authorized return on common stock equity was set at 10.3% based on a 58.1% utility common equity.

In December 2009, the PSCW authorized MGE to increase 2010 rates for retail electric customers by 3.3% or $11.9 million, while gas rates decreased 0.74% or $1.5 million. The increase in retail electric rates was driven by costs for MGE's share of the Elm Road Units and transmission reliability enhancements. Pursuant to the provisions of this rate order, the fuel rules bandwidth effective January 1, 2010, was plus or minus 2%. Authorized return on common stock equity was set at 10.4% based on a 55.3% utility common equity.

b. Fuel Rules.

The PSCW approved new fuel rules that became effective January 1, 2011. The new rules require the PSCW and Wisconsin utilities to automatically defer electric fuel-related costs that fall outside a symmetrical cost tolerance band. Any over/under recovery of the deferred costs is determined on an annual basis and will be adjusted in future billings to its electric retail customers. Under fuel rules, MGE would defer costs, less any excess revenues, if its actual electric fuel costs exceeded 102% of the electric fuel costs allowed in its latest rate order. Excess revenues are defined as revenues in the plan year that provide MGE with a greater return on common equity than authorized by the PSCW in MGE's latest rate order. Conversely, MGE is required to defer the benefit of lower costs if actual electric fuel costs were less than 98% of the electric fuel costs allowed in that order.

As of September 30, 2011, MGE did not defer any electric fuel-related costs. In 2010, a refund of $0.3 million of over collected 2009 fuel costs was refunded on customers' April 2010 bills.

c. Purchased Gas Adjustment Clause.

MGE's natural gas rates are subject to a fuel adjustment clause designed to recover or refund the difference between the actual cost of purchased gas and the amount included in rates. Differences between the amounts billed to customers and the actual costs recoverable are deferred and recovered or refunded in future periods by means of prospective monthly adjustments to rates. At September 30, 2011 and December 31, 2010, MGE had over collected $1.1 million and $4.8 million, respectively. These amounts were recorded in other current liabilities on the consolidated balance sheet.