MGE Energy (MGEE) 10-Q 5 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 31, 2015
Document And Entity Information [Line Items]
Entity Registrant Name	MGE Energy Inc
Entity Central Index Key	1,161,728
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Amendment Flag	false
Trading Symbol	MGEE
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Well known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock Shares Outstanding		34,668,370
MGE [Member]
Document And Entity Information [Line Items]
Entity Registrant Name	Madison Gas and Electric Company
Entity Central Index Key	61,339
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Common Stock Shares Outstanding		17,347,894

MGE Energy Inc Consolidated Sta

MGE Energy Inc Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Operating Revenues:
Regulated electric revenues	$ 121,453	$ 112,869	$ 319,174	$ 308,418
Regulated gas revenues	17,431	21,404	108,028	163,335
Nonregulated revenues	1,911	862	5,853	2,392
Total Operating Revenues	140,795	135,135	433,055	474,145
Operating Expenses:
Fuel for electric generation	17,055	9,838	41,624	35,836
Purchased power	18,484	21,303	62,614	58,779
Cost of gas sold	4,299	11,039	57,868	107,679
Other operations and maintenance	38,721	37,587	120,895	118,267
Depreciation and amortization	11,182	10,376	33,026	30,191
Other general taxes	4,877	4,872	14,951	14,861
Total Operating Expenses	94,618	95,015	330,978	365,613
Operating Income	46,177	40,120	102,077	108,532
Other income, net	2,564	2,636	7,115	10,736
Interest expense, net	(5,036)	(5,141)	(15,135)	(14,550)
Income before income taxes	43,705	37,615	94,057	104,718
Income tax provision	(15,351)	(14,286)	(33,946)	(39,585)
Net Income (Loss)	$ 28,354	$ 23,329	$ 60,111	$ 65,133
Earnings Per Share of Common Stock (basic and diluted)	$ 0.82	$ 0.67	$ 1.73	$ 1.88
Dividends per share of common stock	$ 0.295	$ 0.283	$ 0.860	$ 0.826
Weighted Average Shares Outstanding (basic and diluted)	34,668	34,668	34,668	34,668

Madison Gas and Electric Compan

Madison Gas and Electric Company Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Operating Revenues:
Regulated electric revenues		$ 121,453	$ 112,869	$ 319,174	$ 308,418
Regulated gas revenues		17,431	21,404	108,028	163,335
Nonregulated revenues		1,911	862	5,853	2,392
Total Operating Revenues		140,795	135,135	433,055	474,145
Operating Expenses:
Fuel for electric generation		17,055	9,838	41,624	35,836
Purchased power		18,484	21,303	62,614	58,779
Cost of gas sold		4,299	11,039	57,868	107,679
Other operations and maintenance		38,721	37,587	120,895	118,267
Depreciation and amortization		11,182	10,376	33,026	30,191
Other general taxes		4,877	4,872	14,951	14,861
Income tax provision		15,351	14,286	33,946	39,585
Total Operating Expenses		94,618	95,015	330,978	365,613
Operating Income		46,177	40,120	102,077	108,532
Other Income and Deductions:
Equity in earnings in ATC				6,568	7,306
Total Other Income and Deductions		2,564	2,636	7,115	10,736
Interest Expense:
Net Interest Expense		5,036	5,141	15,135	14,550
Net Income (Loss)		28,354	23,329	60,111	65,133
MGE [Member]
Operating Revenues:
Regulated electric revenues		121,460	112,875	319,191	308,435
Regulated gas revenues		17,435	21,410	108,039	163,351
Nonregulated revenues		1,911	862	5,853	2,392
Total Operating Revenues		140,806	135,147	433,083	474,178
Operating Expenses:
Fuel for electric generation		17,057	9,841	41,630	35,843
Purchased power		18,488	21,307	62,624	58,790
Cost of gas sold		4,302	11,045	57,879	107,695
Other operations and maintenance		38,561	37,309	120,269	117,593
Depreciation and amortization		11,170	10,364	32,991	30,156
Other general taxes		4,877	4,872	14,951	14,861
Income tax provision		14,401	13,338	31,218	36,180
Total Operating Expenses		108,856	108,076	361,562	401,118
Operating Income	[1]	31,950	27,071	71,521	73,060
Other Income and Deductions:
AFUDC - equity funds		206	255	501	3,306
Equity in earnings in ATC		2,398	2,423	6,568	7,306
Income tax provision		(977)	(984)	(2,763)	(3,390)
Other expense, net		(73)	(111)	(288)	(351)
Total Other Income and Deductions	[1]	1,554	1,583	4,018	6,871
Income before interest expense		33,504	28,654	75,539	79,931
Interest Expense:
Interest on long-term debt		5,123	5,225	15,410	15,714
Other interest, net		37	44	52	52
AFUDC - borrowed funds		(67)	(84)	(163)	(1,090)
Net Interest Expense		5,093	5,185	15,299	14,676
Net Income Including Noncontrolling Interest		28,411	23,469	60,240	65,255
Less Net Income Attributable to Noncontrolling Interest, net of tax		(6,633)	(6,653)	(19,812)	(19,784)
Net Income (Loss)		$ 21,778	$ 16,816	$ 40,428	$ 45,471
[1]	*Amounts are shown net of the related tax expense, consistent with the presentation on the MGE Consolidated Statement of Income.

MGE Energy Inc Consolidated St4

MGE Energy Inc Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Comprehensive Income [Abstract]
Net Income	$ 28,354	$ 23,329	$ 60,111	$ 65,133
Other comprehensive income (loss), net of tax:
Unrealized (loss) gain on available-for-sale securities, net of tax	(85)	95	(180)	56
Comprehensive Income	$ 28,269	$ 23,424	$ 59,931	$ 65,189

Madison Gas and Electric Compa5

Madison Gas and Electric Company Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Other comprehensive income/(loss), net of tax:
Unrealized (loss) gain on available-for-sale securities, net of tax	$ (85)	$ 95	$ (180)	$ 56
Comprehensive Income	28,269	23,424	59,931	65,189
MGE [Member]
Net Income	28,411	23,469	60,240	65,255
Other comprehensive income/(loss), net of tax:
Unrealized (loss) gain on available-for-sale securities, net of tax	(28)	43	(137)	(54)
Total comprehensive income including noncontrolling interest	28,383	23,512	60,103	65,201
Less: Comprehensive income attributable to Noncontrolling Interest, net of tax	(6,633)	(6,653)	(19,812)	(19,784)
Comprehensive Income	$ 21,750	$ 16,859	$ 40,291	$ 45,417

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) (Parantheticals) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Unrealized gain (loss) on available-for-sale securities, tax (benefit) expense	$ (56)	$ 63	$ (120)	$ 38
MGE [Member]
Unrealized gain (loss) on available-for-sale securities, tax (benefit) expense	$ (19)	$ 29	$ (92)	$ (36)

MGE Energy Inc Consolidated St7

MGE Energy Inc Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating Activities:
Net Income	$ 60,111	$ 65,133
Items not affecting cash:
Depreciation and amortization	33,026	30,191
Deferred income taxes	7,370	24,376
Provision for doubtful receivables	(78)	1,001
Employee benefit plan expenses	2,500	(814)
Equity earnings in ATC	(6,568)	(7,306)
Other items	(154)	(843)
Changes in working capital items:
Decrease in current assets	39,034	13,318
Decrease in current liabilities	(18,231)	(7,515)
Dividend income from ATC	4,732	5,762
Cash contributions to pension and other postretirement plans	(12,460)	(2,449)
Other noncurrent items, net	13,373	118
Cash Provided by Operating Activities	122,655	120,972
Investing Activities:
Capital expenditures	(52,311)	(66,138)
Capital contributions to investments	(785)	(1,830)
Other	(85)	(1,265)
Cash Used for Investing Activities	(53,181)	(69,233)
Financing Activities:
Cash dividends paid on common stock	(29,816)	(28,634)
Repayment of long-term debt	(3,128)	(3,069)
Repayment of short-term debt	(7,000)	0
Other	(1,018)	(130)
Cash Used for Financing Activities	(40,962)	(31,833)
Change in cash and cash equivalents	28,512	19,906
Cash and cash equivalents at beginning of period	65,755	68,813
Cash and Cash Equivalents at End of Period	$ 94,267	$ 88,719

Madison Gas and Electric Compa8

Madison Gas and Electric Company Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Items not affecting cash:
Depreciation and amortization	$ 33,026	$ 30,191
Deferred income taxes	7,370	24,376
Provision for doubtful receivables	(78)	1,001
Employee benefit plan expenses	2,500	(814)
Equity earnings in ATC	(6,568)	(7,306)
Other items	(154)	(843)
Changes in working capital items:
Decrease in current assets	39,034	13,318
Decrease in current liabilities	(18,231)	(7,515)
Dividend income from ATC	4,732	5,762
Cash contributions to pension and other postretirement plans	(12,460)	(2,449)
Other noncurrent items, net	13,373	118
Cash Provided by Operating Activities	122,655	120,972
Investing Activities:
Capital expenditures	(52,311)	(66,138)
Capital contributions to investments	(785)	(1,830)
Other	(85)	(1,265)
Cash Used for Investing Activities	(53,181)	(69,233)
Financing Activities:
Repayment of long-term debt	(3,128)	(3,069)
Repayment of short-term debt	(7,000)	0
Other	(1,018)	(130)
Cash Used for Financing Activities	(40,962)	(31,833)
Change in cash and cash equivalents	28,512	19,906
Cash and cash equivalents at beginning of period	65,755	68,813
Cash and Cash Equivalents at End of Period	94,267	88,719
MGE [Member]
Operating Activities:
Net Income	60,240	65,255
Items not affecting cash:
Depreciation and amortization	32,991	30,156
Deferred income taxes	4,510	23,811
Provision for doubtful receivables	(78)	1,001
Employee benefit plan expenses	2,500	(814)
Equity earnings in ATC	(6,568)	(7,306)
Other items	234	(446)
Changes in working capital items:
Decrease in current assets	46,806	13,258
Decrease in current liabilities	(15,876)	(5,457)
Dividend income from ATC	4,732	5,762
Cash contributions to pension and other postretirement plans	(12,460)	(2,449)
Other noncurrent items, net	13,076	(24)
Cash Provided by Operating Activities	130,107	122,747
Investing Activities:
Capital expenditures	(52,311)	(66,138)
Capital contributions to investments	(533)	(1,420)
Other	(90)	(1,087)
Cash Used for Investing Activities	(52,934)	(68,645)
Financing Activities:
Cash dividends paid to parent by MGE	(20,000)	(26,500)
Distributions to parent from noncontrolling interest	(12,007)	(17,778)
Equity contribution received by noncontrolling interest	3,053	1,420
Repayment of long-term debt	(3,128)	(3,069)
Repayment of short-term debt	(7,000)	0
Other	(682)	0
Cash Used for Financing Activities	(39,764)	(45,927)
Change in cash and cash equivalents	37,409	8,175
Cash and cash equivalents at beginning of period	4,562	14,808
Cash and Cash Equivalents at End of Period	$ 41,971	$ 22,983

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 94,267	$ 65,755
Accounts receivable, less reserves	35,507	41,614
Other accounts receivables, less reserves	6,549	7,610
Unbilled revenues	21,252	31,262
Materials and supplies, at average cost	19,258	17,121
Fossil fuel	14,195	8,098
Stored natural gas, at average cost	16,998	21,036
Prepaid taxes	14,507	38,910
Regulatory assets - current	9,331	8,360
Deferred income taxes - current	0	3,482
Other current assets	9,916	10,711
Total Current Assets	241,780	253,959
Regulatory assets	155,469	156,823
Other deferred assets and other	10,028	7,018
Property, Plant, and Equipment:
Property, plant, and equipment, net	1,207,520	1,189,077
Construction work in progress	25,015	19,029
Total Property, Plant, and Equipment	1,232,535	1,208,106
Investments	74,016	71,760
Total Assets	1,713,828	1,697,666
Current Liabilities:
Long-term debt due within one year	4,245	4,182
Short-term debt	0	7,000
Accounts payable	35,854	41,655
Accrued interest and taxes	3,996	5,086
Accrued payroll related items	10,141	11,241
Deferred income taxes	945	0
Regulatory liabilities - current	4,376	0
Derivative liabilities	8,880	6,901
Other current liabilities	5,821	13,931
Total Current Liabilities	74,258	89,996
Other Credits:
Deferred income taxes	345,127	342,045
Investment tax credit - deferred	1,094	1,223
Regulatory liabilities	24,467	22,715
Accrued pension and other postretirement benefits	78,879	90,201
Derivative liabilities	48,070	46,560
Other deferred liabilities and other	60,476	50,269
Total Other Credits	558,113	553,013
Capitalization:
Common shareholders equity	689,374	659,401
Long-term debt	392,083	395,256
Total Capitalization	$ 1,081,457	$ 1,054,657
Commitments and contingencies (see Footnote 8)
Total Liabilities and Capitalization	$ 1,713,828	$ 1,697,666
MGE [Member]
Current Assets:
Cash and cash equivalents	41,971	4,562
Accounts receivable, less reserves	35,507	41,614
Affiliate receivables	602	7,112
Other accounts receivables, less reserves	6,490	7,524
Unbilled revenues	21,252	31,262
Materials and supplies, at average cost	19,258	17,121
Fossil fuel	14,195	8,098
Stored natural gas, at average cost	16,997	21,035
Prepaid taxes	13,418	39,103
Regulatory assets - current	9,331	8,360
Deferred income taxes - current	0	1,271
Other current assets	9,881	10,683
Total Current Assets	188,902	197,745
Affiliate receivable long-term	4,898	5,295
Regulatory assets	155,469	156,823
Other deferred assets and other	7,908	4,977
Property, Plant, and Equipment:
Property, plant, and equipment, net	1,206,828	1,188,351
Construction work in progress	25,015	19,029
Total Property, Plant, and Equipment	1,231,843	1,207,380
Investments	70,533	68,402
Total Assets	1,659,553	1,640,622
Current Liabilities:
Long-term debt due within one year	4,245	4,182
Short-term debt	0	7,000
Accounts payable	35,847	41,654
Accrued interest and taxes	3,950	5,039
Accrued payroll related items	10,141	11,241
Deferred income taxes	946	0
Regulatory liabilities - current	4,376	0
Derivative liabilities	8,880	6,901
Other current liabilities	5,600	11,350
Total Current Liabilities	73,985	87,367
Other Credits:
Deferred income taxes	337,233	334,773
Investment tax credit - deferred	1,094	1,223
Regulatory liabilities	24,467	22,715
Accrued pension and other postretirement benefits	78,879	90,201
Derivative liabilities	48,070	46,560
Other deferred liabilities and other	60,475	50,267
Total Other Credits	550,218	545,739
Capitalization:
Common shareholders equity	506,720	486,571
Noncontrolling interest	136,547	125,689
Total Equity	643,267	612,260
Long-term debt	392,083	395,256
Total Capitalization	$ 1,035,350	$ 1,007,516
Commitments and contingencies (see Footnote 8)
Total Liabilities and Capitalization	$ 1,659,553	$ 1,640,622

Consolidated Balance Sheets (10

Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Receivables, Net
Reserve for uncollectible accounts receivable	$ 3,418	$ 4,329
Reserve for uncollectible other accounts receivable	702	420
MGE [Member]
Receivables, Net
Reserve for uncollectible accounts receivable	3,418	4,329
Reserve for uncollectible other accounts receivable	$ 702	$ 420

MGE Energy Inc Consolidated S11

MGE Energy Inc Consolidated Statements of Common Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]
Beginning balance, shares at Dec. 31, 2013		34,668
Beginning balance, value at Dec. 31, 2013	$ 617,510	$ 34,668	$ 316,268	$ 266,197	$ 377
Increase (Decrease) In Stockholders' Equity [Roll Forward]
Net Income	65,133			65,133
Other comprehensive income (loss)	56				56
Common stock dividends declared	(28,634)			(28,634)
Cash in lieu of fractional shares related to stock split	(80)			(80)
Ending balance, shares at Sep. 30, 2014		34,668
Ending balance, value at Sep. 30, 2014	653,985	$ 34,668	316,268	302,616	433
Beginning balance, shares at Dec. 31, 2014		34,668
Beginning balance, value at Dec. 31, 2014	659,401	$ 34,668	316,268	308,007	458
Cumulative effect of new accounting principle (See Footnote 4) at Dec. 31, 2014	(142)			(142)
Beginning balance, value - Adjusted at Dec. 31, 2014	659,259			307,865
Increase (Decrease) In Stockholders' Equity [Roll Forward]
Net Income	60,111			60,111
Other comprehensive income (loss)	(180)				(180)
Common stock dividends declared	(29,816)			(29,816)
Ending balance, shares at Sep. 30, 2015		34,668
Ending balance, value at Sep. 30, 2015	$ 689,374	$ 34,668	$ 316,268	$ 338,160	$ 278

Madison Gas and Electric Comp12

Madison Gas and Electric Company Consolidated Statements of Common Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	MGE [Member]	Common Stock [Member]	Common Stock [Member]MGE [Member]	Additional Paid-In Capital [Member]MGE [Member]	Retained Earnings [Member]	Retained Earnings [Member]MGE [Member]	Accumulated Other Comprehensive (Loss)/Income [Member]	Accumulated Other Comprehensive (Loss)/Income [Member]MGE [Member]	Noncontrolling Interest [Member]MGE [Member]
Beginning balance, shares at Dec. 31, 2013			34,668	17,348
Beginning balance, value at Dec. 31, 2013		$ 576,454		$ 17,348	$ 192,417		$ 247,534		$ 192	$ 118,963
Increase (Decrease) In Stockholders' Equity [Roll Forward]
Net Income		65,255					45,471			19,784
Other comprehensive income (loss)	$ 56	(54)						$ 56	(54)
Cash dividends paid to parent by MGE		(26,500)					(26,500)
Equity contribution received by noncontrolling interest		1,420								1,420
Distributions to parent from noncontrolling interest		(17,778)								(17,778)
Ending balance, shares at Sep. 30, 2014			34,668	17,348
Ending balance, value at Sep. 30, 2014		598,797		$ 17,348	192,417		266,505		138	122,389
Beginning balance, shares at Dec. 31, 2014			34,668	17,348
Beginning balance, value at Dec. 31, 2014		612,260		$ 17,348	192,417		276,662		144	125,689
Cumulative effect of new accounting principle (See Footnote 4) at Dec. 31, 2014	(142)	(142)				$ (142)	(142)
Beginning balance, value - Adjusted at Dec. 31, 2014		612,118					276,520
Increase (Decrease) In Stockholders' Equity [Roll Forward]
Net Income		60,240					40,428			19,812
Other comprehensive income (loss)	$ (180)	(137)						$ (180)	(137)
Cash dividends paid to parent by MGE		(20,000)					(20,000)
Equity contribution received by noncontrolling interest		3,053								3,053
Distributions to parent from noncontrolling interest		(12,007)								(12,007)
Ending balance, shares at Sep. 30, 2015			34,668	17,348
Ending balance, value at Sep. 30, 2015		$ 643,267		$ 17,348	$ 192,417		$ 296,948		$ 7	$ 136,547

Consolidated Statements of Comm

Consolidated Statements of Common Equity (Unaudited) (Parentheticals) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Consolidated Statements of Common Equity
Dividends per share of common stock	$ 0.295	$ 0.283	$ 0.860	$ 0.826

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation - MGE Energy and MGE . This report is a combined report of MGE Energy and MGE. References in this report to "MGE Energy" are to MGE Energy, Inc. and its subsidiaries. References in this report to "MGE" are to Madison Gas and Electric Company. MGE Power Elm Road and MGE Power West Campus own electric generating assets and lease those assets to MGE. Both entities are variable interest entities under applicable authoritative accounting guidance. MGE is considered the primary beneficiary of these entities as a result of contractual agreements. As a result, MGE has consolidated MGE Power Elm Road and MGE Power West Campus . See Footnote 2 of Notes to Consolidated Financial Statements under Item 8, Financial Statements and Supplementary Data, of MGE Energy ' s and MGE ' s 2014 Annual Report on Form 10-K. The accompanying consolidated financial statements as of September 30, 2015 , and for the three and nine months ended , are unaudited, but include all adjustments that MGE Energy and MGE management consider necessary for a fair statement of their respective financial statements. All adjustments are of a normal, recurring nature exce pt as otherwise disclosed. The year-end consolidated balance sheet information was derived from the audited balance sheet appearing in MGE Energy's and MGE's 2014 Annual Report on Form 10-K, but does not include all disclosures required by accounting pr inciples generally accepted in the United States of America. These notes should be read in conjunction with the financial statements and the notes on pages 52 through 1 01 of the 2014 Annual Report on Form 10-K .

Equity and Financing Arrangemen

Equity and Financing Arrangements	9 Months Ended
	Sep. 30, 2015
Equity and Financing Arrangements Disclosure [Abstract]
Equity and Financing Arrangements	Equity and Financing Arrangements. a. Common Stock - MGE Energy. MGE Energy sells shares of its common stock through its Stock Plan. Those shares may be newly issued shares or shares that MGE Energy has purchased in the open market for resale to participants in the Stock Plan. All sales under the S tock P lan are covered by a shelf registration statement that MGE Energy filed with the SEC. For both the nine months ended September 30, 2015 and 2014 , MGE Energy did not issue any new shares of common stock under the Stock Plan. b. Dilutive Shares Calculation - MGE Energy. MGE Energy does not hold any dilutive securities. c. Credit Facilities - MGE Energy and MGE. On June 1, 2015, MGE Energy and MGE entered into new revolving credit agreements, and terminated their existing revolving credit agreements. MGE Energy entered into a Credit Agreemen t with an aggregate commitment of $50 million (MGE Energy Credit Agreement) with various financial institutions, as lenders, and JPMorgan Chase Bank, N.A., as administrative agent. Also, MGE entered into two revolving credit agreements: a Credit Agreement with an aggregate co mmitment of $60 million (MGE JPM Credit Agreement) with various financial institutions, as lenders, and JPMorgan Chase Bank, N.A., as administrative agent, and a Credit Agreement with an aggregate commitment of $40 million (MGE USB Credit Agreement) with v arious financial institutions, as lenders, and U.S. Bank National Association, a s administrative agent. The MGE Energy Credit Agreement, the MGE JPM Credit Agreement, and the MGE USB Credit Agreement are collectively referred to as the Credit Agreements. A s of September 30, 2015 , neither MGE Energy nor MGE had any borrowings outstanding under the Credit Agreements, and MGE had no commercial paper outstanding. The Credit Agreements have a term expiring on June 1, 2020 . Borrowings under the Credit Agreements may bear interest at a rate based upon either a "floating rate" or a "Eurodollar Rate" adjusted for statutory reserve requirements, plus an adder based upon the credit ratings assign ed to MGE's senior unsecured long-term debt securities. The "floating rate" is calculated on a dail y basis as the highest of a prime rate, a Federal Funds effective rate plus 0.5% per annum, or a Eurodollar Rate for a one-month interest period plus 1%. The " floating rate " adder ranges from zero to 0.125%. The "Eurodollar Rate" is calculated as provided in the Credit Agreements. The " Eurodollar Rate " adder ranges from 0.625% to 1.125%.

Investment in ATC

Investment in ATC	9 Months Ended
	Sep. 30, 2015
Equity Method Investments and Joint Ventures [Abstract]
Investment in ATC	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 as required by Wisconsin law. 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 nine months ended September 30, 2015 and 2014 , MGE Transco recorded the following : Nine Months Ended September 30, (In thousands) 2015 2014 Equity in earnings from investment in ATC $ 6,568 $ 7,306 Dividends received from ATC 4,732 5,762 Capital contributions to ATC 533 1,420 MGE Transco ' s investment in ATC as of September 30, 2015 , and December 31, 2014 , was $ 70.0 million and $ 67.7 million, respectively. On October 30 , 201 5 , MGE Transco made a $ 0.2 million capital contribution to AT C. At September 30, 2015 , MGE is the majority owner, and MGE Energy, the holdin g company, is the minority owner of MGE Transco. MGE Energy's proportionate share of the equity and net income of MGE Transco is classified wit hin the MGE financial statements as noncontrolling interest. ATC ' s summarized financial data for the three and nine months ended September 30, 2015 and 2014 , is as follows: Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Operating revenues $ 164,515 $ 163,643 $ 482,043 $ 486,970 Operating expenses (78,059) (76,561) (238,336) (229,589) Other income, net 585 693 566 1,403 Interest expense, net (23,655) (22,204) (72,310) (66,442) Earnings before members' income taxes $ 63,386 $ 65,571 $ 171,963 $ 192,342

Chattel Paper Agreements

Chattel Paper Agreements	9 Months Ended
	Sep. 30, 2015
Transfers and Servicing [Abstract]
Chattel Paper Agreements	Chattel Paper Agreements - MGE Energy and MGE. MGE makes available to qualifying customers a financing program for the purchase and installation of energy-related equipment that will provide more efficient use of utility service at the customer's property. The energy-related equipment installed at the customer sites is used to secure the customer loans. MGE is a party to a chattel paper purchase agreement with a financial institution under which it can sell or finance an undivided interest with rec ourse, in up to $ 10.0 million of the financing program receivables, until July 31, 2016. The length of the MGE guarantee to the financial institution varies from one to ten years depending on the term of the underlying customer loan . The loan balances outstanding at September 30, 2015 , approximate the fair value of the energy-related equipment acting as collateral. MGE accounts for these agreements as secured borrowings. Prior to the Transfers and Servicing Asset authoritative accounting guida nce that became effective in 2015, these agreements were treated as off-balance sheet arrangements. Beginning January 1, 2015, these agreements are included as assets and liabilities in the consolidated balance sheet. As of September 30, 2015 , assets (other accounts receivable and other deferred assets) and liabilities (accounts payable and other deferred liabilities) increased approximately $ 3.8 million as a cumulative result of the guidance. In addition, the cumulative e ffect of this guidance resulted in a $ 0.1 million reduction in retained earnings. As of September 30, 2015 , the remaining contractual maturities of the chattel paper agreements were as follows: (In thousands) 2015 2016 2017 2018 Thereafter Total Repurchase-to-Maturity Transactions: Loans $ 132 $ 735 $ 472 $ 504 $ 1,963 $ 3,806

Taxes

Taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Taxes	Taxes - MGE Energy and MGE . MGE Ene rgy's effective income tax rates for the three and nine months ended September 30, 2015 , were 35.1 % and 36.1 %, respectively, compared to 38.0 % and 37.8 % for the same periods in 2014 . MGE's effective income tax rates for the three and nine months ended September 30, 2015 , were 35.1 % and 36.1 %, respectively, compared to 37.9 % and 37.8 % for the same periods in 2014 . The decrease in the effective tax rates is due in part to a higher domestic manufacturing deduction, offset by lower AFUDC equity earnings in 2015.

Pension and Other Postretiremen

Pension and Other Postretirement Plans	9 Months Ended
	Sep. 30, 2015
Compensation and Retirement Disclosure [Abstract]
Pension and Other Postretirement Plans	Pension and Other Postretirement Plans - MGE Energy and MGE. MGE maintains qualified and nonqualified pension plans, health care, and life insurance benefits. Additionally, MGE has def ined contribution 401(k) benefit plans. The following table presents the components of MGE Energy's and MGE's net periodic benefit costs recognized for the three and nine months ended September 30, 2015 and 2014 . A portion of the net periodic benefit cost is capitalized within the consolidated balance she ets. Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Pension Benefits Components of net periodic (benefit) cost: Service cost $ 1,878 $ 1,536 $ 5,715 $ 4,609 Interest cost 3,594 3,367 10,936 10,102 Expected return on assets (5,930) (5,467) (18,045) (16,402) Amortization of: Prior service cost 6 51 18 152 Actuarial loss 1,393 180 4,240 539 Net periodic (benefit) cost $ 941 $ (333) $ 2,864 $ (1,000) Postretirement Benefits Components of net periodic (benefit) cost: Service cost $ 194 $ 241 $ 580 $ 722 Interest cost 392 564 1,176 1,691 Expected return on assets (355) (478) (1,063) (1,432) Amortization of: Transition obligation - 1 1 2 Prior service benefit (337) (487) (1,009) (1,462) Actuarial loss 133 28 397 86 Net periodic (benefit) cost $ 27 $ (131) $ 82 $ (393)

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation - MGE Energy and MGE. Under MGE Energy ' s Performance Unit Plan, eligible employees may receive performance units that entitle the holder to receive a cash payment equal to the value of a designated number of shares of MGE Energy's common stock, plus dividend equivalent payments thereon, at the end of the set performance period. On February 20, 2015, 18,948 units were granted based on the MGE Energy closing stock price as of th at date. Units are subject to a five-year graded vesting schedule. On the grant d ate, MGE Energy and MGE measure the cost of the employee services received in exchange for a performance unit award based on the current market value of MGE Energy common stoc k. The fair value of the awards has been subsequently re-measured at September 30, 2015 , as required by applicable accounting standards. Changes in fair value have been recognized as compensation cost. Since this amount is re-measured quarterly throughout t he vesting period, the compensation cost is subject to variability. For nonretirement eligible employees, stock based compensation costs are accrued and recognized using the graded vesting method. Compensation cost for retirement eligible employees or em ployees that will become retirement eligible during the vesting schedule are recognized on an abridged horizon. In December 2013, a Director Incentive Plan was approved for the non-employee members of the Board of Directors. This plan is similar to MGE En ergy's Performance Unit Plan for eligible employees described above. Under the plan, a non-employee director can receive performance units that entitle the holder to receive a cash payment equal to the value of a designated number of shares of MGE Energy's common stock, plus dividend payments, at the end of the set performance period. The units are subject to a three-year graded vesting schedule. In January 2015 , 3,794 units were granted. For accounting purposes, the awards will be measured similarly to the employee unit awards. During the nine months ended September 30, 2015 and 2014 , MGE recorded $ 0.4 million and $ 0.9 million, res pectively, in compensation expense as a result of awards under the plans. In January 2015, cash payments of $ 1.3 million were distributed relating to awards that were granted in 2010. During the nine months ended September 30, 2015 , MGE recorded a $ 0.2 million gain on 4,676 units forfeited. No forfeitures occurred during the nine months ended September 30, 2014 . At September 30, 2015 , $ 4.2 million of outstanding awards are vested, and of this amount no cash settlements have occurred.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies - MGE Energy and MGE . a. Environmental. MGE Energy and MGE are subject to frequently changing local, state, and federal regulations concerning air quality, water quality, land use, threatened and endangered species, hazardous materials handling, and solid waste disposal. These regulations affect the manner in which they conduct their operations, the costs of those operations, as well as capital and operating expenditures. Regulatory initiatives, proposed rules, and co urt challenges to adopted rules, have the potential to have a material effect on our capital expenditures and operating costs. These initiatives, proposed rules, and court challenges include: EPA ' s Effluent Limitations Guidelines (ELG) and Standards for S team Electric Power Generating Point Source Category In September 2015, the EPA released its final rule setting Effluent Limitations Guidelines (ELG) for the steam electric power generating industry. The ELG rule establishes federal limits on the amount of metals and other pollutants that can be discharged in wastewater from new and existing steam electric generation plants. The ELG rule mostly covers pollutants that are captured by certain air pollution control and via wet ash handling systems at coal-burn ing power plants with units greater than 50 megawatt (MW) generation capacity. Although we are still reviewing the ELG rule, we anticipate that some equipment upgrades may be necessary at the Columbia and Elm Road plants to comply with the new discharge st andards. The rule will go into effect in 2018 and will be applied to Wisconsin-based power plants as they renew their WPDES permits. MGE cannot accurately estimate the costs associated with the ELG rule without a more thorough evaluation. However, managem ent believes that any compliance costs will be recovered in future rates based on previous treatment of environmental compliance projects. EPA Cooling Water Intake Rules (Section 316(b)) Section 316(b) of the Clean Water Act (CWA) requires that the cooling water intake structures at electric power plants meet best available technology standards so that mortality from entrainment (drawing aquatic life into a plant's cooling system) and impingement (trapping aquatic life on screens) are reduced. The EP A finalized its 316(b) rule for existing facilities in 2014. Section 316(b) requirements are implemented in Wisconsin through modifications to plants' WPDES permits, which govern plant wastewater discharges. WDNR is currently developing rules to implement the EPA 316(b) rule. Our WCCF facility already employs a system that meets the 316(b) rule. Our Blount plant has conducted studies showing that it will likely be in compliance with this rule when its WPDES permit is renewed in 2017. The operator of our Columbia plant plans to conduct an intake study to demonstrate compliance with the 316(b) rule and/or identify design criteria needed to meet the new rule requirements prior to Columbia's 2017 WPDES permit renewal. The exact requirements at Blount and Columbia, however, will not be known until the WDNR finalizes its rule, approves the plant operators' approach, and those sites' WPDES permits are modified to account for this rule. Nonetheless, MGE expects that the 316(b) rule will not have material effec ts on its existing plants. EPA's Greenhouse Gas (GHG) Reduction Guidelines under the Clean Air Act 111 ( d ) Rule On August 3, 2015, the EPA finalized its Clean Power Plan rule setting guidelines for states to use in developing plans to control GHG emissions from existing fossil fuel-fired electric generating units (EGUs) and systems. When fully implemented in 2030, the Clean Power Plan is projected to reduce GHG emissions from this sector by 32 percent below 2005 levels. States are given up to three years to submit a plan to meet the reduction goals and are expected to meet interim goals starting in 2022 and the final goal in 2030. Implementation of the rule is expected to have a direct impact on coal and natural gas fired generating units, including possible changes in dispatch and additional operating costs. On October 23, 2015, several states, including Wisconsin, and several state regulatory bodies filed a joint petition seeking to have the U.S. Court of Appeals for the District of Columbia Circuit stay t he effectiveness of the Clean Power Plant rule, which would otherwise become effective on December 22, 2015, and seeking expedited review of the petitioners ' challenges to the legality of the adoption of the rule. MGE is evaluating the rule and its requ irements. Given the pending legal proceedings and the need for a yet-to-be-developed state implementation plan or federal implementation plan, the nature and timing of any final requirements is subject to uncertainty. If the rule remains substantially in i ts present form, it is expected to have a material impact on MGE. National Ambient Air Quality Standards (NAAQS) The EPA's NAAQS regulations have been developed to set ambient levels of six pollutants to protect sensitive populations (primary NAAQS) and the environment (secondary NAAQS) from the negative effects of exposure to these pollutants at higher levels. MGE is following developments for several NAAQS, including for particulate matter, nitrogen dioxide, sulfur dioxide, and ozone. Further discussio n on sulfur dioxide and ozone NAAQS follows. For additional information on the NAAQS process, see Footnote 18.d. of Notes to Consolidated Financial Statements under Item 8, Financial Statements and Supplementary Data, of MGE Energy's and MGE's 2014 Annual Report on Form 10-K. Sulfur Dioxide (SO 2 ) NAAQS The EPA's new 1-hour SO 2 NAAQS has been in place since 2010 and initial attainment/nonattainment designations by states were due in 2013. However, the EPA was sued by environmental groups for not making thes e designations in a timely and proper manner. In March 2015, the EPA entered into a court-approved consent decree requiring 1-hour SO 2 attainment/nonattainment area designations to be completed in three phases extending out until 2020. In August 2015, the EPA published its data requirements rule that lays out expectations, designation process options, and timeframes for states and tribes to meet. Under this new rule, states must submit their first designation proposals in July 2016 for those areas that cont ain large stationary sources of SO 2 (sources that emit over a threshold mass of SO 2 , and/or over a threshold emissions rate). These proposals must identify one of the following options for demonstrating attainment with the 1-hour SO 2 NAAQS: modeling of SO 2 emissions; monitoring of SO 2 emissions; or limiting large stationary sources to 2,000 ton per year of SO 2 emissions by January 13, 2017. The EPA must make final designation determinations for these areas between 2017 and 2020 depending on the area. In Ma rch 2015, MGE's Columbia plant was identified in the Federal Register as meeting the criteria of a large stationary source of SO 2 (based on 2012 data). As such, the State of Wisconsin must submit an attainment/nonattainment area designation plan for Columb ia County (the county in which the Columbia plant is located). Since the 2012 data was collected, Columbia has installed pollution control equipment that has lowered its total SO 2 emissions and its SO 2 emissions rate. However, we will not know with any cer tainty if Columbia County will be determined to be in attainment until the State of Wisconsin completes its attainment/nonattainment demonstration and the EPA approves it. The outcome of this designation may have an adverse effect on the operation of the C olumbia plant. MGE will monitor and participate in developments with the Columbia County designation process. Management believes compliance costs will be recovered in future rates based on previous treatment of environmental compliance projects. Ozone NAAQS In October 2015, the EPA revised the primary and secondary ozone NAAQS, lowering each to 70 ppb. Based on current ozone monitoring data, it appears that Milwaukee County (where our Elm Road Units are located) may not attain the lowered standards. Cu rrent ozone monitoring data suggests that Dane and Columbia Counties (where our WCCF/Blount and Columbia Units are located, respectively) will meet the new ozone NAAQS. Nonetheless, final attainment designations for these three counties will be based upon air monitoring data for years 2014-2016 and must be approved by EPA. Once these designations are complete, the State of Wisconsin will develop implementation plans for each county designated as nonattainment, which could affect plant operations within the nonattainment counties. These implementation plans are not expected to be finalized until 2017 at the earliest. MGE will continue to monitor developments, attainment designations, and state actions and implementation plans . EPA's Cross-State Air Pollution Rule In July 2011, the EPA finalized its Cross-State Air Pollution Rule (CSAPR) as a court-ordered replacement for its Clean Air Interstate Rule (CAIR) that had been remanded in 2008. CSAPR is an interstate air pollution transport rule designed to reduce ozone and fine particulate matter (PM2.5) air levels in areas that the EPA has determined are being affected by pollution from neighboring and upwind states. CSAPR has been the subject of extensive litigation. That litigation had delayed implementation a nd created uncertainty, however, the most recent D.C. Circuit ruling clears the way for CSAPR to be fully implemented in Wisconsin. Some uncertainty remains as to the ozone season NO x budget for Wisconsin. In late 2014, the EPA tolled CSAPR's original comp liance deadlines by three years and MGE's affected facilities must now meet their Phase I reduction obligations in 2015 and Phase II in 2017. MGE anticipates meeting its CSAPR requirements at all of our affected facilities by applying reductions achieved from recent pollution control installations and early reduction efforts. We do not anticipate this rule to have a significant impact on MGE. Clean Air Visibility Rule (CAVR) Columbia may be subject to the best available retrofit technology (BART) regulati ons, a subsection of the EPA's Clean Air Visibility Rule (CAVR), which may require pollution control retrofits. Columbia's pollution control upgrades and the EPA's stance that compliance with the CSAPR equals compliance with BART should mean that Columbia will not need to do additional work to meet BART requirements. At this time, however, the BART regulatory obligations, compliance strategies, and costs remain uncertain due to the legal uncertainty surrounding CSAPR. EPA's Coal Combustion Residuals Rule I n December 2014, the EPA finalized its Disposal of Coal Combustion Residuals from Electric Utilities (CCR) rule. The rule became effective on October 19, 2015. It provides that coal ash will be regulated as a solid waste, and defines what ash use activitie s would be considered generally exempt beneficial reuse of coal ash. The rule also regulates landfills, ash ponds, and other surface impoundments for coal combustion residuals by regulating their design, location, monitoring, and operation. Landfills and i mpoundments that cannot meet design criteria will need to formally close within defined timeframes. The Columbia and Elm Road Units co-owners and plant operators are evaluating the final rule to determine what changes may be necessary at those facilities and the associated timeframes. We anticipate that some design and operational changes may need to be made at these facilities. Review of our Elm Road facility has indicated that the costs to comply with this rule are not expected to be significant. We are still evaluating the rule's full effects at Columbia, however, Columbia's operator has developed a preliminary implementation schedule for meeting the various deadlines spelled out in the rule. Management believes compliance costs will be recovered in futu re rates based on previous treatment of environmental compliance projects. Columbia Based upon current available information, compliance with various environmental requirements and initiatives is expected to result in significant additional operating and capital expenditures at Columbia as noted below. Columbia Clean Air Act Litigation Columbia is a coal-fired generating station operated by WPL in which WPL, WPSC, and MGE have ownership interests. In December 2009, the EPA sent a Notice of Violation (NOV) to MGE as one of the co-owners of Columbia. The NOV alleged that WPL and the Columb ia co-owners failed to comply with appropriate pre-construction review and permitting requirements and, as a result, violated the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA, and the Wiscon sin SIP. In April 2013, the EPA filed a lawsuit against the co-owners of Columbia asserting similar allegations. In September 2010 and April 2013, the Sierra Club filed civil lawsuits against WPL alleging violations of the CAA at Columbia and other Wiscons in facilities operated by WPL. In June 2013, the court approved and entered a consent decree entered by the EPA, Sierra Club, and the co-owners of Columbia to resolve these claims, while admitting no liability. One of the requirements of the consent decree requires installation of a SCR system at Columbia Unit 2 by December 31, 2018. Installation of the SCR has been approved by the PSCW. MGE's share of the projected cost for the SCR system is approximately $19 -$ 29 million. In addition, the consent decree es tablishes emission rate limits for SO 2 , NO x , and particulate matter and annual plant-wide emission caps for SO 2 and NO x . MGE intends to seek recovery in future rates of the costs associated with its compliance with the terms of the final consent decree an d currently expects to recover any material compliance costs. b . Legal Matters. MGE is involved in various legal matters that are being defended and handled in the normal course of business . MGE maintains accruals for such costs that are probable of being incurred and subject to reasonable estimation. The accrued amount for these matters is not material to the financial statements . c. Purchase Contracts. MGE Energy and MGE have entered into various commodity supply, transportation, and storage contracts to meet their obligations to deliver electricity and natural gas to customers. As of September 30, 2015 , the future commitments related to these purchase contracts were as follows: (In thousands) 2015 2016 2017 2018 2019 Coal (a) $ 6,211 $ 21,639 $ 10,664 $ 6,560 $ 3,850 Natural gas Transportation & storage (b) 5,229 18,117 17,983 17,901 16,971 Supply (c) 10,704 11,127 - - - $ 22,144 $ 50,883 $ 28,647 $ 24,461 $ 20,821 (a ) Total coal commitments for the Columbia and Elm Road Units, including transportation. Fuel procurement for MGE's jointly owned Columbia and Elm Road Units is handled by WPL and WEPCO, respectively, who are the operators of those facilities. If any minimum purchase obligations must be paid under these contracts, management believes these obligations would be considered costs of service and recoverable in rates. (b) MGE's natural gas transportation and storage contracts require fixed monthly payments for firm supply pipeline transportation and storage capacity. The pricing components of the fixed monthly payments for the transportation and storage contracts are established by FERC but may be subject to change. (c) These commitments include market-bas ed pricing. Management expects to recover these costs in future customer rates. d. Asset Retirement Obligation. MGE Energy and MGE are required to record a liability for the fair value of an ARO to be recognized in the period in which it is incurred if it can be reasonably estimated. The offsetting associated asset retirement costs are capitalized as a long-lived asset and depreciated over the asset's useful life. As o f September 30, 2015 , MGE recorded an obligation of $2. 3 million for the fair value of its legal liability for asset retirement obligations (AROs) associated with the effect of the final Coal Combustion Residual Rule at Columbia. MGE has regulatory treatmen t and recognizes regulatory assets or liabilities for the timing differences between when we recover legal AROs in rates and when those costs would actually be recognized .

Derivative and Hedging Instrume

Derivative and Hedging Instruments	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative and Hedging Instruments	Derivative and Hedging Instruments - MGE Energy and MGE. a. Purpose. As part of its regular operations, MGE enters into contracts, including options, swaps, futures, forwards, and other contractual commitments, to manage its exposure to commodity prices . To the extent that these contracts are derivatives, MGE assesses whether or not the normal purchases or normal sales exclusion applies. For contracts to which this exclusion cannot be applied, MGE Energy and MGE recognize such deri vatives in the consolidated balance sheets at fair value. MGE's commodity derivative activities are conducted in accordance with its electric and gas risk management program, which is approved by the PSCW and limits the volume MGE can hedge with specific r isk management strategies. The maximum length of time over which cash flows related to energy commodities can be hedg ed is four years. If the derivative qualifies for regulatory deferral, the derivatives are marked to fair value and are offset with a corre sponding regulatory asset or liability. The deferred gain or loss is recognized in earnings in the delivery month applicable to the instrument. Gains and losses related to hedges qualifying for regulatory treatment are recoverable in gas rates through the PGA or in electric rates as a component of the fuel rules mechanism. b. Notional Amounts. The gross notional volume of open derivatives is as follows: September 30, 2015 December 31, 2014 Commodity derivative contracts 343,560 MWh 448,000 MWh Commodity derivative contracts 6,547,500 Dth 4,405,000 Dth FTRs 3,286 MW 1,854 MW c . Financial Statement Presentation . MGE purchases and sells exchange-traded and over-the-counter options, swaps, and future contracts. These arrangements are primarily entered into to help stabilize the price risk associated with gas or power purchases. These transactions are employed by both MGE ' s gas and electric segments. Additionally, as a result of the firm transmission agreements that MGE holds on electricity transmission paths in the MISO market, MGE holds FTRs. An FTR is a financial instrument th at entitles the holder to a stream of revenues or charges based on the differences in hourly day-ahead energy prices between two p oints on the transmission grid. The fair values of these instruments are offset with a corresponding regulatory asset/liabilit y depending on whether they are in a net loss/gain position. Depending on the nature of the instrument, the gain or loss associated with these transactions will be reflected as cost of gas sold, fuel for electric generation, or purchased power expense in t he delivery month applicable to the instrument. At September 30, 2015 , and December 31, 2014 , the cost basis of exchange traded derivatives and FTRs exceeded their fair value by $ 0.4 million and $ 1.6 millio n, respectively. MGE is a party to a purchased power agreement that provides MGE with firm capacity and energy during a base term from June 1, 2012, through May 31, 2022. The agreement also allows MGE an option to extend the contract after the base term. The agreement is accounted for as a derivative contract and is recognized at its fair value on the consolidated balance sheet s . However, the derivative qualifies for regulatory deferral and is recognized with a corresponding regulatory asset or liability d epending on whether the fair value is in a loss or gain position. The fair value of the contract at September 30, 2015 , and December 31, 2014 , reflects a loss position of $ 57.0 million and $ 53.4 million, respectively. The actual cost will be recognized in purchased power e xpense in the month of purchase . The following table summarizes the fair value of the derivative instruments on the consolidated balance sheet s . All derivative in struments in this table are presented on a gross basis and are calculated prior to the netting of instruments with the same counterparty under a master netting agreement as well as the netting of collateral. For financial statement purposes, MGE Energy and MGE have netted instruments with the same counterparty under a master netting agreement as well as the netting of collateral. At September 30, 2015 , MGE Energy and MGE had the right to reclaim collateral (a receivable) of $ 0.8 million . Asset Derivatives Liability Derivatives (In thousands) Balance Sheet Location Fair Value Balance Sheet Location Fair Value September 30, 2015 Commodity derivative contracts Other current assets $ 375 Derivative liability (current) $ 1,196 Commodity derivative contracts Other deferred charges 65 Derivative liability (long-term) 62 FTRs Other current assets 370 Derivative liability (current) - PPA N/A N/A Derivative liability (current) 8,880 PPA N/A N/A Derivative liability (long-term) 48,070 December 31, 2014 Commodity derivative contracts Other current assets $ 130 Derivative liability (current) $ 2,262 Commodity derivative contracts Other deferred charges 93 Derivative liability (long-term) 171 FTRs Other current assets 642 Derivative liability (current) - PPA N/A N/A Derivative liability (current) 6,870 PPA N/A N/A Derivative liability (long-term) 46,560 The foll owing tables show the ef fect of netting arrangements for recognized derivative assets and liabilities that are subject to a master netting arr angement or similar arrangement on the consolidated balance sheets . Offsetting of Derivative Assets (In thousands) Gross amounts Gross amounts offset in balance sheet Collateral posted against derivative positions Net amount presented in balance sheet September 30, 2015 Commodity derivative contracts $ 440 $ (431) $ - $ 9 FTRs 370 - - 370 December 31, 2014 Commodity derivative contracts $ 223 $ (223) $ - $ - FTRs 642 - - 642 Offsetting of Derivative Liabilities (In thousands) Gross amounts Gross amounts offset in balance sheet Collateral posted against derivative positions Net amount presented in balance sheet September 30, 2015 Commodity derivative contracts $ 1,258 $ (431) $ (827) $ - PPA 56,950 - - 56,950 December 31, 2014 Commodity derivative contracts $ 2,433 $ (223) $ (2,179) $ 31 PPA 53,430 - - 53,430 The following table s summarize the unrealized and realized gains (losses) related to the derivative instruments on the consolidated balance sheet s at September 30, 2015 and 2014 , and the consolidated income statement s for the three and nine months ended September 30, 2015 and 2014 . 2015 2014 (In thousands) Current and long-term regulatory asset Other current assets Current and long-term regulatory asset Other current assets Three Months Ended September 30: Balance at July 1, $ 56,048 $ 455 $ 48,853 $ 676 Unrealized loss (gain) 4,036 - 5,329 - Realized (loss) gain reclassified to a deferred account (408) 408 (314) 314 Realized (loss) gain reclassified to income statement (2,278) (91) (1,184) (249) Balance at September 30, $ 57,398 $ 772 $ 52,684 $ 741 Nine Months Ended September 30: Balance at January 1, $ 54,998 $ 1,001 $ 63,893 $ 411 Unrealized loss (gain) 8,514 - (18,090) - Realized (loss) gain reclassified to a deferred account (1,700) 1,700 1,120 (1,120) Realized (loss) gain reclassified to income statement (4,414) (1,929) 5,761 1,450 Balance at September 30, $ 57,398 $ 772 $ 52,684 $ 741 Realized losses (gains) 2015 2014 (In thousands) Fuel for electric generation/ purchased power Cost of gas sold Fuel for electric generation/ purchased power Cost of gas sold Three Months Ended September 30: Commodity derivative contracts $ 862 $ (17) $ 480 $ (18) FTRs (233) - (97) - PPA 1,757 - 1,068 - Nine Months Ended September 30: Commodity derivative contracts $ 1,860 $ 1,742 $ (5,376) $ (1,367) FTRs (607) - (929) - PPA 3,348 - 461 - MGE's commodity derivativ e contracts, FTRs, and PPA are subject to regulatory deferral. These derivatives are marked to fair value and are offset with a corresponding regulatory asset or liability. Realized gains and losses are deferred on the consolidated balance sheet s and are recognized in earnings in the delivery month applicable to the instrument. As a result of the above described treatment, there are no unrealized gains or losses that flow through earnings. The PPA has a provi sion that may require MGE to post collateral if MGE's debt rating falls below investment grade (i.e., below BBB-). The amount of collateral that it may be required to post varies from $ 20.0 million to $ 40.0 million, depending on MGE's nominated capacity amount. As of September 30, 2015 , no collateral is required to be, or has been, posted. Certain counterparties extend MGE a credit limit. If MGE exceeds these limits, the counterparties may require collateral to be posted. As of September 30, 2015 and December 31, 2014 , certain counterparties were in a net liability of less than $ 0.1 million. Nonperformance of counterparties to the non-exchange traded derivatives could expose MGE to credit loss. However, MGE enters into transactions only with companies that meet or exceed strict credit guidelines, and it monitors these counterparties on an ongoing basis to mitigate nonperformance risk in its portfolio. As of September 30, 2015 , no counterpart ies have defaulted.

Rate Matters

Rate Matters	9 Months Ended
	Sep. 30, 2015
Regulated Operations [Abstract]
Rate Matters	Rate Matters - MGE Energy and MGE. a. Rate P roceedings. In July 2015 , the PSCW approved MGE ' s request to extend the current accounting treatment for transmission related costs through 2016, conditioned upon MGE not filing a base rate case for 2016 . This treatment would allow MGE to reflect any differential between transmission costs reflected in rates and actual costs incurred in its next rate case filing. On December 23, 2014, the PSCW authorized MGE to increase 2015 rates for retail electric custo mers by 3.8 % or $ 15.4 million and to decrease gas rates by 2.0 % or $ 3.8 million. The increase in retail electric rates cover costs associated with the constructi on of emission-reduction equipment at Columbia, improvements and reliability of the state's electric transmission system, fuel and purchased power related to coal delivery costs, partially offset by lower cost as a result of market conditions for pension a nd post retirement benefit costs. The authorized return on common stock equity is 10.2 %. The PSCW also approved changes to customer rates and rate design for gas service that became effective January 1, 2015 . Gas rate design consists of a fixed monthly customer charge and a variable charge tied to actual usage, in addition to the separate charge for natural gas commodity costs (PGA) . T he change shifted more of the rate recovery to the monthly charge, reflecting the related fixed costs of providing gas services, and reduced the variable usage-based charge. Thus, gas net income is expected to be more evenly distributed during the year and less sensitive to weather. A similar, but much smaller rate design shift was also approved for electric rates. On July 26, 2013, the PSCW authorized MGE to freeze electric and natural gas rates at 2013 levels for 2014. The order authorized 100 % AFUDC on the Columbia scrubber construction project and deferral of increased costs related to ATC and MISO network upgrade fees. As part of the rate freeze plan authorized by the PSCW, effective January 1, 2014, approximately $ 6.3 million associated with a 2012 fuel rule surplus credit was required to be refunded to customers and was amortized in 2014. The fuel credit accrued interest at MGE's weighted cost of capital. The authorized return on common stock equity was unchanged at 10.3 %. b. Fuel R ules. Fuel rules require the PSCW and Wisconsin utilities to defer electric fuel-related costs that fall outside a symmetrical cost tolerance band around the amount approved for a utility in its annual fuel proceedings. Any over/under recovery of the actual costs is determined on an annual basis and is adjusted in future billings to electric retail customers. The fuel rules bandwidth is currently set at plus or minus 2 %. Under fuel rules, MGE would defer costs, les s 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 year in question that provide MGE with a greater ret urn 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 th at order. In August 2015, the PSCW approved on an interim basis MGE ' s application to implement a fuel credit associated with its fuel savings for 2015. The fuel credit established a mechanism to return the fuel savings to electric customers via a bill cre dit during the period from September 2015 to December 31, 2015. The fuel credit was based on $5.9 million of actual fuel savings deferred through June 30, 2015. Approximately $2.7 million is expected to be returned to customers through December 31, 2015. T he application further proposes a fuel credit to cover expected fuel savings for 2016 in the amount of approximately $5.0 million based on anticipated fuel costs. The actual fuel savings will depend upon the completion of the annual PSCW fuel cost audits f or 2015 and 2016 . As of September 30, 2015 , MGE has deferred $ 7.6 million of 2015 electric fuel-related savings that are outside the range authorized by the PSCW. In September 2015, MGE returned $ 0.7 million of total electric fuel-related savings on customer bills. As part of the rate freeze plan authorized by the PSCW for 2014, $ 4.7 million of the approximately $ 6.3 million associated with the 2012 fuel rule credit was amortized against purchased power expense during the nine months ended September 30, 2014 . 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, 2015 , and December 31, 2014 , MGE had over collected $ 1.1 million and $ 1.2 million, respectively, which was recorded in other current liabilities on the consolidated balance sheets.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments - MGE Energy and MGE. Fair value is defined as the price that would be received to sell an asset or would be paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. The accounting standard clarifies that fair value should be based on the assumptions market participants would use when pricing the asset or liability including ass umptions about risk. The standard also establishes a three level fair value hierarchy based upon the observability of the assumptions used and requires the use of observable market data when available. The levels are: Level 1 - Pricing inputs are quoted p rices within active markets for identical assets or liabilities. Level 2 - Pricing inputs are quoted prices within active markets for similar assets or liabilities; quoted prices for identical or similar instruments in markets that are not active; and mod el-derived valuations that are correlated with or otherwise verifiable by observable market data. Level 3 - Pricing inputs are unobservable and reflect management ' s best estimate of what market participants would use in pricing the asset or liability. a. Fair Value of Financial Assets and Liabilities Recorded at the Carrying Amount. At September 30, 2015 , and December 31, 2014 , the carrying amount of cash , cash equivalents, and outstanding commercial paper approximates fair market value due to the short maturity of those investments and obligations. The estimated fair market value of MGE Energy's and MGE ' s long-term debt is based on quoted market prices for similar financial instruments at September 30, 2015 , and December 31, 2014 . Since long-term debt is not traded in an active market, it is classified as Level 2. The estimated fair market value of MGE Energy's and MGE's financial instruments are as follows: September 30, 2015 December 31, 2014 (In thousands) Carrying Amount Fair Value Carrying Amount Fair Value MGE Energy Assets: Cash and cash equivalents $ 94,267 $ 94,267 $ 65,755 $ 65,755 Liabilities: Short-term debt - commercial paper - - 7,000 7,000 Long-term debt* 396,562 446,176 399,690 457,420 MGE Assets: Cash and cash equivalents $ 41,971 $ 41,971 $ 4,562 $ 4,562 Liabilities: Short-term debt - commercial paper - - 7,000 7,000 Long-term debt* 396,562 446,176 399,690 457,420 *Includes long-term debt due within one year. b. Recurring Fair Value Measurements. The following table presents the balances of assets and liabilities measured at fair value on a recurring basis for MGE Energy and MGE. Fair Value as of September 30, 2015 (In thousands) Total Level 1 Level 2 Level 3 MGE Energy Assets: Derivatives, net $ 379 $ - $ - $ 379 Exchange-traded investments 627 627 - - Total Assets $ 1,006 $ 627 $ - $ 379 Liabilities: Derivatives, net (a) $ 57,777 $ 316 $ - $ 57,461 Deferred compensation 3,160 - 3,160 - Total Liabilities $ 60,937 $ 316 $ 3,160 $ 57,461 MGE Assets: Derivatives, net $ 379 $ - $ - $ 379 Exchange-traded investments 122 122 - - Total Assets $ 501 $ 122 $ - $ 379 Liabilities: Derivatives, net (a) $ 57,777 $ 316 $ - $ 57,461 Deferred compensation 3,160 - 3,160 - Total Liabilities $ 60,937 $ 316 $ 3,160 $ 57,461 Fair Value as of December 31, 2014 (In thousands) Total Level 1 Level 2 Level 3 MGE Energy Assets: Derivatives, net $ 642 $ - $ - $ 642 Exchange-traded investments 927 927 - - Total Assets $ 1,569 $ 927 $ - $ 642 Liabilities: Derivatives, net (a) $ 55,640 $ 1,012 $ - $ 54,628 Deferred compensation 2,832 - 2,832 - Total Liabilities $ 58,472 $ 1,012 $ 2,832 $ 54,628 MGE Assets: Derivatives, net $ 642 $ - $ - $ 642 Exchange-traded investments 350 350 - - Total Assets $ 992 $ 350 $ - $ 642 Liabilities: Derivatives, net (a) $ 55,640 $ 1,012 $ - $ 54,628 Deferred compensation 2,832 - 2,832 - Total Liabilities $ 58,472 $ 1,012 $ 2,832 $ 54,628 (a) These amounts are shown gross and exclude $0.8 million and $2.2 million of collateral that was posted against derivative positions with counterparties as of September 30, 2015, and December 31, 2014, respectively. No transfers were made in or out of Level 1 or Level 2 for the nine months ended September 30, 2015 . I nvestments include exchange-traded investment securities valued using quoted prices on active exchanges and are therefore classified as Level 1. Derivatives include exchange-traded derivative c ontracts, over-the-counter transactions, a purchased power agreement, and FTRs. Most exchange-traded derivative contracts are valued based on unadjusted quoted prices in active markets and are therefore class ified as Level 1. A small number of exchange-traded derivative contracts are valued using quoted market pricing in markets with insufficient volumes and are therefore classified as Level 3. Transactions done with an over-the-counter party are on inactive m arkets and are therefore considered unobservable and classified as Level 3. These transactions are valued based on quoted prices from markets with similar exchange traded transactions. FTRs are priced based upon monthly auction results for identical or sim ilar instruments in a closed market with limited data available and are therefore classified as Level 3. The purchased power agreement (see Footnote 9 ) was valued using an internally-developed pricing model and therefore is classified as Level 3. The mod el projects future market energy prices and compares those prices to the projected power costs to be incurred under the contract. Inputs to the model require significant management judgment and estimation. Future energy prices are based on a forward power pricing curve using exchange-traded contracts in the electric futures market , where such exchange-traded contracts exist, and upon calculations based on forward gas prices, where such exchange-traded contracts do not exist. A basis adjustment is applied to t he market energy price to reflect the price differential between the market price delivery point and the counterparty delivery point. The historical relationship between the delivery points is reviewed and a discount (below 100%) or premium (above 100%) is derived. This comparison is done for both peak times when demand is high and off peak times when demand is low. If the basis adjustment is lowered, the fair value measurement will decrease, and if the basis adjustment is increased, the fair value measurement will increase. The projected power costs anticipated to be incurred under the purchased power agreement are determined using many factors, including historical generating costs, future prices, and expected fuel mix of the counterparty. An increase in the projected fuel costs would result in a decrease in the fair value measurement of the purchased power agreement. A significant input that MGE estimates is the counterparty ' s fuel mix in determining the projected power cost. MGE also consi ders the assumptions that market participants would use in valuing the asset or liability. This consideration includes assumptions about market risk such as liquidity, volatility , and contract duration. The fair value model uses a discount rate that incorp orates discounting, credit, and model risks. This model is prepared by members of MGE ' s Energy Accounting department. On a quarterly basis, management in the Energy Supply and Finance departments review the assumptions, inputs, and fair value measurement s. The following table presents the significant unobservable inputs used in the pricing model. Model Input Significant Unobservable Inputs September 30, 2015 December 31, 2014 Basis adjustment: On peak 97.4 % 98.1 % Off peak 95.4 % 95.0 % Counterparty fuel mix: Internal generation 60% - 75% 50% - 70% Purchased power 40% - 25% 50% - 30% The deferred compensation plan allows participants to defer certain cash compensation into a notional investment account. These amounts are included within other deferred liabilities in the consolidated balance sheets of MGE Energy and MGE. The notional investments earn interest based upon the semiannual rate of U.S. Treasury Bills having a 26 w eek maturity increased by 1 % compounded monthly with a minimum annual rate of 7 %, compounded monthly. The notional investments are based upon observable market data , however, since the deferred compensation obligations themselves are not exchanged in an active mark et, they are classified as Level 2 . The following table summarizes the changes in Level 3 assets and liabilities measured at fair value on a recurring basis for both MGE Energy and MGE. Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Beginning balance $ (56,194) $ (49,349) $ (53,986) $ (64,628) Realized and unrealized gains (losses): Included in regulatory liabilities (assets) (888) (3,752) (3,096) 11,528 Included in other comprehensive income - - - - Included in earnings (2,285) (1,419) (4,497) 5,837 Included in current assets - - - (89) Purchases 6,364 6,371 17,497 19,900 Sales - - 34 (60) Issuances - - - - Settlements (4,079) (4,952) (13,034) (25,589) Transfers in and/or out of Level 3 - - - - Balance as of September 30, $ (57,082) $ (53,101) $ (57,082) $ (53,101) Total gains (losses) included in earnings attributed to the change in unrealized gains (losses) related to assets and liabilities held at September 30, (b) $ - $ - $ - $ - The following table presents total realized and unrealized gains (losses) included in income for Level 3 assets and liabilities measured at fair value on a recurring basis for both MGE Energy and MGE ( b ). Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Purchased Power Expense $ (2,302) $ (1,411) $ (4,515) $ 5,845 Cost of Gas Sold Expense 17 (8) 18 (8) Total $ (2,285) $ (1,419) $ (4,497) $ 5,837 (b) MGE's exchange-traded derivative contracts, over-the-counter party transactions, purchased power agreement, and FTRs are subject to regulatory deferral. These derivatives are therefore marked to fair value and are offset in the financial statements with a corresponding regulatory asset or liability.

New Accounting Pronouncements

New Accounting Pronouncements	9 Months Ended
	Sep. 30, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements - MGE Energy and MGE. a. Transfers and Servicing Assets . In June 2014, the FASB issued authoritative guidance within the Codification ' s Transfers and Servicing topic that provides guidance on the accounting and disclosures for repurchase-to-maturity transactions, securities lending transactions, and repurchase financings. This authoritative guidance became effective January 1, 2015. The authoritative guidance ch anged the accounting for the Chattel Paper program and required additional disclosures. Prior to adoption of the standard, Chattel Paper was treated as an off-balance sheet arrangement. See Footnote 4 for additional information. b. Revenue from Contracts with Customers . In May 2014, the FASB issued authoritative guidance within the Codification ' s Revenue Recognition topic that provides guidance on the recognition, measurement, and disclosure of revenue from contracts with customers. This authoritative gui dance was scheduled to become effective January 1, 2017. In July 2015, the FASB deferred the effective date to January 1, 2018. MGE Energy and MGE are currently assessing the impact this pronouncement will have on their financial statements. c. Consolidat ions . In February 2015, the FASB issued authoritative guidance within the Codification ' s Consolidation topic that provides guidance on the evaluation of certain legal entities for consolidation purposes. This authoritative guidance will become effective J anuary 1, 2016. The impact of this guidance on our financial statements is not expected to be material. d. Debt Issuance Costs . In April 2015, the FASB issued authoritative guidance within the Codification ' s Interest topic that provides guidance on the presentation of debt issuance costs in financial statements. This authoritative guidance will become effective January 1, 2016. The authoritative guidance changes the presentation of debt issuance costs on the balance sheet from an asset to a direct deduct ion from the related debt liability. The impact of this guidance on our financial statements is not expected to be material. e. Cloud Computing Arrangements . In April 2015, the FASB issued authoritative guidance within the Codification ' s Software topic t hat provides guidance on the accounting treatment of cloud computer arrangements. This authoritative guidance will become effective January 1, 2016. The authoritative guidance provides criteria for determining whether a cloud computing arrangement contains a software license that should be accounted for as internal-use software. The impact of this guidance on our financial statements is not expected to be material. f. Inventory Measurement . In July 2015, the FASB issued authoritative guidance within the Codification ' s Inventory topic that provides guidance on the subsequent measurement of inventory. This authoritative guidance will become effective January 1, 2017. The authoritative guidance changes the subsequent measurement of inventory from the lower o f cost or market to the lower of cost or net realizable value. MGE Energy and MGE are currently assessing the impact this pronouncement will have on their financial statements.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment Information	Segment Information - MGE Energy and MGE. MGE Energy operates in the following business segments: electric utility, gas utility, nonregulated energy, transmission investment, and all other. See MGE Energy ' s and MGE ' s 2014 Annual Report on Form 10-K for additional discussion of each of these segments. The following table s show segment information for MGE Energy ' s operations for the indicated periods : (In thousands) MGE Energy Electric Gas Non- Regulated Energy Transmission Investment All Others Consolidation/ Elimination Entries Consolidated Total Three Months Ended September 30, 2015 Operating revenues $ 121,453 $ 17,431 $ 1,911 $ - $ - $ - $ 140,795 Interdepartmental revenues 163 3,855 9,866 - - (13,884) - Total operating revenues 121,616 21,286 11,777 - - (13,884) 140,795 Depreciation and amortization (7,584) (1,714) (1,872) - (12) - (11,182) Other operating expenses (80,202) (16,906) (36) (15) (161) 13,884 (83,436) Operating income (loss) 33,830 2,666 9,869 (15) (173) - 46,177 Other (deductions) income, net 141 (7) - 2,397 33 - 2,564 Interest (expense) income, net (2,798) (804) (1,491) - 57 - (5,036) Income (loss) before taxes 31,173 1,855 8,378 2,382 (83) - 43,705 Income tax (provision) benefit (10,321) (732) (3,362) (962) 26 - (15,351) Net income (loss) $ 20,852 $ 1,123 $ 5,016 $ 1,420 $ (57) $ - $ 28,354 Three Months Ended September 30, 2014 Operating revenues $ 112,869 $ 21,404 $ 862 $ - $ - $ - $ 135,135 Interdepartmental revenues 156 1,614 10,674 - - (12,444) - Total operating revenues 113,025 23,018 11,536 - - (12,444) 135,135 Depreciation and amortization (6,931) (1,575) (1,858) - (12) - (10,376) Other operating expenses (74,573) (22,199) (35) - (276) 12,444 (84,639) Operating income (loss) 31,521 (756) 9,643 - (288) - 40,120 Other income, net 136 8 - 2,423 69 - 2,636 Interest (expense) income, net (2,832) (808) (1,545) - 44 - (5,141) Income (loss) before taxes 28,825 (1,556) 8,098 2,423 (175) - 37,615 Income tax (provision) benefit (10,758) 651 (3,251) (963) 35 - (14,286) Net income (loss) $ 18,067 $ (905) $ 4,847 $ 1,460 $ (140) $ - $ 23,329 Nine Months Ended September 30, 2015 Operating revenues $ 319,174 $ 108,028 $ 5,853 $ - $ - $ - $ 433,055 Interdepartmental revenues 400 8,871 29,566 - - (38,837) - Total operating revenues 319,574 116,899 35,419 - - (38,837) 433,055 Depreciation and amortization (22,372) (5,018) (5,601) - (35) - (33,026) Other operating expenses (239,963) (96,063) (122) (15) (626) 38,837 (297,952) Operating income (loss) 57,239 15,818 29,696 (15) (661) - 102,077 Other (deductions) income, net 247 (33) - 6,568 333 - 7,115 Interest (expense) income, net (8,385) (2,398) (4,516) - 164 - (15,135) Income (loss) before taxes 49,101 13,387 25,180 6,553 (164) - 94,057 Income tax (provision) benefit (15,868) (5,370) (10,106) (2,637) 35 - (33,946) Net income (loss) $ 33,233 $ 8,017 $ 15,074 $ 3,916 $ (129) $ - $ 60,111 Nine Months Ended September 30, 2014 Operating revenues $ 308,418 $ 163,335 $ 2,392 $ - $ - $ - $ 474,145 Interdepartmental revenues 401 7,130 32,017 - - (39,548) - Total operating revenues 308,819 170,465 34,409 - - (39,548) 474,145 Depreciation and amortization (19,909) (4,700) (5,547) - (35) - (30,191) Other operating expenses (229,286) (144,907) (105) - (672) 39,548 (335,422) Operating income (loss) 59,624 20,858 28,757 - (707) - 108,532 Other (deductions) income, net 2,999 (44) - 7,306 475 - 10,736 Interest (expense) income, net (7,571) (2,429) (4,676) - 126 - (14,550) Income (loss) before taxes 55,052 18,385 24,081 7,306 (106) - 104,718 Income tax provision (19,602) (7,378) (9,665) (2,924) (16) - (39,585) Net income (loss) $ 35,450 $ 11,007 $ 14,416 $ 4,382 $ (122) $ - $ 65,133 The following table s show segment information for MGE ' s operations for the indicated periods : (In thousands) MGE Electric Gas Non- Regulated Energy Transmission Investment Consolidation/ Elimination Entries Consolidated Total Three Months Ended September 30, 2015 Operating revenues $ 121,460 $ 17,435 $ 1,911 $ - $ - $ 140,806 Interdepartmental revenues 156 3,851 9,866 - (13,873) - Total operating revenues 121,616 21,286 11,777 - (13,873) 140,806 Depreciation and amortization (7,584) (1,714) (1,872) - - (11,170) Other operating expenses* (90,511) (17,635) (3,398) (15) 13,873 (97,686) Operating income (loss)* 23,521 1,937 6,507 (15) - 31,950 Other (deductions) income, net* 129 (10) - 1,435 - 1,554 Interest expense, net (2,798) (804) (1,491) - - (5,093) Net income 20,852 1,123 5,016 1,420 - 28,411 Less: Net income attributable to noncontrolling interest, net of tax - - - - (6,633) (6,633) Net income attributable to MGE $ 20,852 $ 1,123 $ 5,016 $ 1,420 $ (6,633) $ 21,778 Three Months Ended September 30, 2014 Operating revenues $ 112,875 $ 21,410 $ 862 $ - $ - $ 135,147 Interdepartmental revenues 150 1,608 10,674 - (12,432) - Total operating revenues 113,025 23,018 11,536 - (12,432) 135,147 Depreciation and amortization (6,931) (1,575) (1,858) - - (10,364) Other operating expenses* (85,314) (21,544) (3,286) - 12,432 (97,712) Operating income (loss)* 20,780 (101) 6,392 - - 27,071 Other income, net* 119 4 - 1,460 - 1,583 Interest expense, net (2,832) (808) (1,545) - - (5,185) Net income (loss) 18,067 (905) 4,847 1,460 - 23,469 Less: Net income attributable to noncontrolling interest, net of tax - - - - (6,653) (6,653) Net income (loss) attributable to MGE $ 18,067 $ (905) $ 4,847 $ 1,460 $ (6,653) $ 16,816 Nine Months Ended September 30, 2015 Operating revenues $ 319,191 $ 108,039 $ 5,853 $ - $ - $ 433,083 Interdepartmental revenues 383 8,860 29,566 - (38,809) - Total operating revenues 319,574 116,899 35,419 - (38,809) 433,083 Depreciation and amortization (22,372) (5,018) (5,601) - - (32,991) Other operating expenses* (255,732) (101,405) (10,228) (15) 38,809 (328,571) Operating income (loss)* 41,470 10,476 19,590 (15) - 71,521 Other (deductions) income, net* 148 (61) - 3,931 - 4,018 Interest expense, net (8,385) (2,398) (4,516) - - (15,299) Net income 33,233 8,017 15,074 3,916 - 60,240 Less: Net income attributable to noncontrolling interest, net of tax - - - - (19,812) (19,812) Net income attributable to MGE $ 33,233 $ 8,017 $ 15,074 $ 3,916 $ (19,812) $ 40,428 Nine Months Ended September 30, 2014 Operating revenues $ 308,435 $ 163,351 $ 2,392 $ - $ - $ 474,178 Interdepartmental revenues 384 7,114 32,017 - (39,515) - Total operating revenues 308,819 170,465 34,409 - (39,515) 474,178 Depreciation and amortization (19,909) (4,700) (5,547) - - (30,156) Other operating expenses* (248,525) (152,182) (9,770) - 39,515 (370,962) Operating income (loss)* 40,385 13,583 19,092 - - 73,060 Other (deductions) income, net* 2,636 (147) - 4,382 - 6,871 Interest expense, net (7,571) (2,429) (4,676) - - (14,676) Net income 35,450 11,007 14,416 4,382 - 65,255 Less: Net income attributable to noncontrolling interest, net of tax - - - - (19,784) (19,784) Net income attributable to MGE $ 35,450 $ 11,007 $ 14,416 $ 4,382 $ (19,784) $ 45,471 *Amounts are shown net of the related tax expense, consistent with the presentation on the MGE Consolidated Statement of Income.

Significant Accounting Policies

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Variable Interest Entities	MGE Power Elm Road and MGE Power West Campus own electric generating assets and lease those assets to MGE. Both entities are variable interest entities under applicable authoritative accounting guidance. MGE is considered the primary beneficiary of these entities as a result of contractual agreements. As a result, MGE has consolidated MGE Power Elm Road and MGE Power West Campus .
Common Stock	MGE Energy sells shares of its common stock through its Stock Plan. Those shares may be newly issued shares or shares that MGE Energy has purchased in the open market for resale to participants in the Stock Plan. All sales under the S tock P lan are covered by a shelf registration statement that MGE Energy filed with the SEC.
Investments - ATC	MGE Transco has accounted for its investment in ATC under the equity method of accounting.
Chattel Paper Agreement	MGE makes available to qualifying customers a financing program for the purchase and installation of energy-related equipment that will provide more efficient use of utility service at the customer's property. The energy-related equipment installed at the customer sites is used to secure the customer loans. MGE is a party to a chattel paper purchase agreement with a financial institution under which it can sell or finance an undivided interest with rec ourse, in up to $ 10.0 million of the financing program receivables, until July 31, 2016. The length of the MGE guarantee to the financial institution varies from one to ten years depending on the term of the underlying customer loan . The loan balances outstanding at September 30, 2015 , approximate the fair value of the energy-related equipment acting as collateral. MGE accounts for these agreements as secured borrowings. Prior to the Transfers and Servicing Asset authoritative accounting guida nce that became effective in 2015, these agreements were treated as off-balance sheet arrangements. Beginning January 1, 2015, these agreements are included as assets and liabilities in the consolidated balance sheet. As of September 30, 2015 , assets (other accounts receivable and other deferred assets) and liabilities (accounts payable and other deferred liabilities) increased approximately $ 3.8 million as a cumulative result of the guidance. In addition, the cumulative e ffect of this guidance resulted in a $ 0.1 million reduction in retained earnings.
Share-based Compensation	Under MGE Energy ' s Performance Unit Plan, eligible employees may receive performance units that entitle the holder to receive a cash payment equal to the value of a designated number of shares of MGE Energy's common stock, plus dividend equivalent payments thereon, at the end of the set performance period. On February 20, 2015, 18,948 units were granted based on the MGE Energy closing stock price as of th at date. Units are subject to a five-year graded vesting schedule. On the grant d ate, MGE Energy and MGE measure the cost of the employee services received in exchange for a performance unit award based on the current market value of MGE Energy common stoc k. The fair value of the awards has been subsequently re-measured at September 30, 2015 , as required by applicable accounting standards. Changes in fair value have been recognized as compensation cost. Since this amount is re-measured quarterly throughout t he vesting period, the compensation cost is subject to variability. For nonretirement eligible employees, stock based compensation costs are accrued and recognized using the graded vesting method. Compensation cost for retirement eligible employees or em ployees that will become retirement eligible during the vesting schedule are recognized on an abridged horizon. In December 2013, a Director Incentive Plan was approved for the non-employee members of the Board of Directors. This plan is similar to MGE En ergy's Performance Unit Plan for eligible employees described above. Under the plan, a non-employee director can receive performance units that entitle the holder to receive a cash payment equal to the value of a designated number of shares of MGE Energy's common stock, plus dividend payments, at the end of the set performance period. The units are subject to a three-year graded vesting schedule. In January 2015 , 3,794 units were granted. For accounting purposes, the awards will be measured similarly to the employee unit awards.
Derivative Hedging	As part of its regular operations, MGE enters into contracts, including options, swaps, futures, forwards, and other contractual commitments, to manage its exposure to commodity prices . To the extent that these contracts are derivatives, MGE assesses whether or not the normal purchases or normal sales exclusion applies. For contracts to which this exclusion cannot be applied, MGE Energy and MGE recognize such deri vatives in the consolidated balance sheets at fair value. MGE's commodity derivative activities are conducted in accordance with its electric and gas risk management program, which is approved by the PSCW and limits the volume MGE can hedge with specific r isk management strategies. The maximum length of time over which cash flows related to energy commodities can be hedg ed is four years. If the derivative qualifies for regulatory deferral, the derivatives are marked to fair value and are offset with a corre sponding regulatory asset or liability. The deferred gain or loss is recognized in earnings in the delivery month applicable to the instrument. Gains and losses related to hedges qualifying for regulatory treatment are recoverable in gas rates through the PGA or in electric rates as a component of the fuel rules mechanism.
Derivative Netting	All derivative in struments in this table are presented on a gross basis and are calculated prior to the netting of instruments with the same counterparty under a master netting agreement as well as the netting of collateral. For financial statement purposes, MGE Energy and MGE have netted instruments with the same counterparty under a master netting agreement as well as the netting of collateral.
Wisconsin Fuel Rules	Fuel rules require the PSCW and Wisconsin utilities to defer electric fuel-related costs that fall outside a symmetrical cost tolerance band around the amount approved for a utility in its annual fuel proceedings. Any over/under recovery of the actual costs is determined on an annual basis and is adjusted in future billings to electric retail customers. The fuel rules bandwidth is currently set at plus or minus 2 %. Under fuel rules, MGE would defer costs, les s 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 year in question that provide MGE with a greater ret urn 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 th at order.
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, 2015 , and December 31, 2014 , MGE had over collected $ 1.1 million and $ 1.2 million, respectively, which was recorded in other current liabilities on the consolidated balance sheets.
New Accounting Pronouncements Disclosure	New Accounting Pronouncements - MGE Energy and MGE. a. Transfers and Servicing Assets . In June 2014, the FASB issued authoritative guidance within the Codification ' s Transfers and Servicing topic that provides guidance on the accounting and disclosures for repurchase-to-maturity transactions, securities lending transactions, and repurchase financings. This authoritative guidance became effective January 1, 2015. The authoritative guidance ch anged the accounting for the Chattel Paper program and required additional disclosures. Prior to adoption of the standard, Chattel Paper was treated as an off-balance sheet arrangement. See Footnote 4 for additional information. b. Revenue from Contracts with Customers . In May 2014, the FASB issued authoritative guidance within the Codification ' s Revenue Recognition topic that provides guidance on the recognition, measurement, and disclosure of revenue from contracts with customers. This authoritative gui dance was scheduled to become effective January 1, 2017. In July 2015, the FASB deferred the effective date to January 1, 2018. MGE Energy and MGE are currently assessing the impact this pronouncement will have on their financial statements. c. Consolidat ions . In February 2015, the FASB issued authoritative guidance within the Codification ' s Consolidation topic that provides guidance on the evaluation of certain legal entities for consolidation purposes. This authoritative guidance will become effective J anuary 1, 2016. The impact of this guidance on our financial statements is not expected to be material. d. Debt Issuance Costs . In April 2015, the FASB issued authoritative guidance within the Codification ' s Interest topic that provides guidance on the presentation of debt issuance costs in financial statements. This authoritative guidance will become effective January 1, 2016. The authoritative guidance changes the presentation of debt issuance costs on the balance sheet from an asset to a direct deduct ion from the related debt liability. The impact of this guidance on our financial statements is not expected to be material. e. Cloud Computing Arrangements . In April 2015, the FASB issued authoritative guidance within the Codification ' s Software topic t hat provides guidance on the accounting treatment of cloud computer arrangements. This authoritative guidance will become effective January 1, 2016. The authoritative guidance provides criteria for determining whether a cloud computing arrangement contains a software license that should be accounted for as internal-use software. The impact of this guidance on our financial statements is not expected to be material. f. Inventory Measurement . In July 2015, the FASB issued authoritative guidance within the Codification ' s Inventory topic that provides guidance on the subsequent measurement of inventory. This authoritative guidance will become effective January 1, 2017. The authoritative guidance changes the subsequent measurement of inventory from the lower o f cost or market to the lower of cost or net realizable value. MGE Energy and MGE are currently assessing the impact this pronouncement will have on their financial statements.
Recurring Fair Value Measurements	Fair value is defined as the price that would be received to sell an asset or would be paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. The accounting standard clarifies that fair value should be based on the assumptions market participants would use when pricing the asset or liability including ass umptions about risk. The standard also establishes a three level fair value hierarchy based upon the observability of the assumptions used and requires the use of observable market data when available. The levels are: Level 1 - Pricing inputs are quoted p rices within active markets for identical assets or liabilities. Level 2 - Pricing inputs are quoted prices within active markets for similar assets or liabilities; quoted prices for identical or similar instruments in markets that are not active; and mod el-derived valuations that are correlated with or otherwise verifiable by observable market data. Level 3 - Pricing inputs are unobservable and reflect management ' s best estimate of what market participants would use in pricing the asset or liability. At September 30, 2015 , and December 31, 2014 , the carrying amount of cash , cash equivalents, and outstanding commercial paper approximates fair market value due to the short maturity of those investments and obligations. The estimated fair market value of MGE Energy's and MGE ' s long-term debt is based on quoted market prices for similar financial instruments at September 30, 2015 , and December 31, 2014 . Since long-term debt is not traded in an active market, it is classified as Level 2. I nvestments include exchange-traded investment securities valued using quoted prices on active exchanges and are therefore classified as Level 1. Derivatives include exchange-traded derivative c ontracts, over-the-counter transactions, a purchased power agreement, and FTRs. Most exchange-traded derivative contracts are valued based on unadjusted quoted prices in active markets and are therefore class ified as Level 1. A small number of exchange-traded derivative contracts are valued using quoted market pricing in markets with insufficient volumes and are therefore classified as Level 3. Transactions done with an over-the-counter party are on inactive m arkets and are therefore considered unobservable and classified as Level 3. These transactions are valued based on quoted prices from markets with similar exchange traded transactions. FTRs are priced based upon monthly auction results for identical or sim ilar instruments in a closed market with limited data available and are therefore classified as Level 3. The purchased power agreement (see Footnote 9 ) was valued using an internally-developed pricing model and therefore is classified as Level 3. The mod el projects future market energy prices and compares those prices to the projected power costs to be incurred under the contract. Inputs to the model require significant management judgment and estimation. Future energy prices are based on a forward power pricing curve using exchange-traded contracts in the electric futures market , where such exchange-traded contracts exist, and upon calculations based on forward gas prices, where such exchange-traded contracts do not exist. A basis adjustment is applied to t he market energy price to reflect the price differential between the market price delivery point and the counterparty delivery point. The historical relationship between the delivery points is reviewed and a discount (below 100%) or premium (above 100%) is derived. This comparison is done for both peak times when demand is high and off peak times when demand is low. If the basis adjustment is lowered, the fair value measurement will decrease, and if the basis adjustment is increased, the fair value measurement will increase. The projected power costs anticipated to be incurred under the purchased power agreement are determined using many factors, including historical generating costs, future prices, and expected fuel mix of the counterparty. An increase in the projected fuel costs would result in a decrease in the fair value measurement of the purchased power agreement. A significant input that MGE estimates is the counterparty ' s fuel mix in determining the projected power cost. MGE also consi ders the assumptions that market participants would use in valuing the asset or liability. This consideration includes assumptions about market risk such as liquidity, volatility , and contract duration. The fair value model uses a discount rate that incorp orates discounting, credit, and model risks. This model is prepared by members of MGE ' s Energy Accounting department. On a quarterly basis, management in the Energy Supply and Finance departments review the assumptions, inputs, and fair value measurement s. The following table presents the significant unobservable inputs used in the pricing model. Model Input Significant Unobservable Inputs September 30, 2015 December 31, 2014 Basis adjustment: On peak 97.4 % 98.1 % Off peak 95.4 % 95.0 % Counterparty fuel mix: Internal generation 60% - 75% 50% - 70% Purchased power 40% - 25% 50% - 30% The deferred compensation plan allows participants to defer certain cash compensation into a notional investment account. These amounts are included within other deferred liabilities in the consolidated balance sheets of MGE Energy and MGE. The notional investments earn interest based upon the semiannual rate of U.S. Treasury Bills having a 26 w eek maturity increased by 1 % compounded monthly with a minimum annual rate of 7 %, compounded monthly. The notional investments are based upon observable market data , however, since the deferred compensation obligations themselves are not exchanged in an active mark et, they are classified as Level 2 .

Investment in ATC (Tables)

Investment in ATC (Tables)	9 Months Ended
	Sep. 30, 2015
Equity Method Investments and Joint Ventures [Abstract]
ATC's Summarized Financial Data	For the nine months ended September 30, 2015 and 2014 , MGE Transco recorded the following : Nine Months Ended September 30, (In thousands) 2015 2014 Equity in earnings from investment in ATC $ 6,568 $ 7,306 Dividends received from ATC 4,732 5,762 Capital contributions to ATC 533 1,420 ATC ' s summarized financial data for the three and nine months ended September 30, 2015 and 2014 , is as follows: Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Operating revenues $ 164,515 $ 163,643 $ 482,043 $ 486,970 Operating expenses (78,059) (76,561) (238,336) (229,589) Other income, net 585 693 566 1,403 Interest expense, net (23,655) (22,204) (72,310) (66,442) Earnings before members' income taxes $ 63,386 $ 65,571 $ 171,963 $ 192,342

Chattel Paper Agreements (Table

Chattel Paper Agreements (Tables)	9 Months Ended
	Sep. 30, 2015
Transfers and Servicing [Abstract]
Schedule of Remaining Contractual Maturities for Chattel Paper Agreements	As of September 30, 2015 , the remaining contractual maturities of the chattel paper agreements were as follows: (In thousands) 2015 2016 2017 2018 Thereafter Total Repurchase-to-Maturity Transactions: Loans $ 132 $ 735 $ 472 $ 504 $ 1,963 $ 3,806

Pension and Other Postretirem30

Pension and Other Postretirement Plans (Tables)	9 Months Ended
	Sep. 30, 2015
Compensation and Retirement Disclosure [Abstract]
Schedule of Net Periodic Benefit Costs	The following table presents the components of MGE Energy's and MGE's net periodic benefit costs recognized for the three and nine months ended September 30, 2015 and 2014 . A portion of the net periodic benefit cost is capitalized within the consolidated balance she ets. Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Pension Benefits Components of net periodic (benefit) cost: Service cost $ 1,878 $ 1,536 $ 5,715 $ 4,609 Interest cost 3,594 3,367 10,936 10,102 Expected return on assets (5,930) (5,467) (18,045) (16,402) Amortization of: Prior service cost 6 51 18 152 Actuarial loss 1,393 180 4,240 539 Net periodic (benefit) cost $ 941 $ (333) $ 2,864 $ (1,000) Postretirement Benefits Components of net periodic (benefit) cost: Service cost $ 194 $ 241 $ 580 $ 722 Interest cost 392 564 1,176 1,691 Expected return on assets (355) (478) (1,063) (1,432) Amortization of: Transition obligation - 1 1 2 Prior service benefit (337) (487) (1,009) (1,462) Actuarial loss 133 28 397 86 Net periodic (benefit) cost $ 27 $ (131) $ 82 $ (393)

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Purchase Contracts, Fiscal Year Maturity Schedule	As of September 30, 2015 , the future commitments related to these purchase contracts were as follows: (In thousands) 2015 2016 2017 2018 2019 Coal (a) $ 6,211 $ 21,639 $ 10,664 $ 6,560 $ 3,850 Natural gas Transportation & storage (b) 5,229 18,117 17,983 17,901 16,971 Supply (c) 10,704 11,127 - - - $ 22,144 $ 50,883 $ 28,647 $ 24,461 $ 20,821 (a ) Total coal commitments for the Columbia and Elm Road Units, including transportation. Fuel procurement for MGE's jointly owned Columbia and Elm Road Units is handled by WPL and WEPCO, respectively, who are the operators of those facilities. If any minimum purchase obligations must be paid under these contracts, management believes these obligations would be considered costs of service and recoverable in rates. (b) MGE's natural gas transportation and storage contracts require fixed monthly payments for firm supply pipeline transportation and storage capacity. The pricing components of the fixed monthly payments for the transportation and storage contracts are established by FERC but may be subject to change. (c) These commitments include market-bas ed pricing. Management expects to recover these costs in future customer rates.

Derivative and Hedging Instru32

Derivative and Hedging Instruments (Tables)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross Notional Volume of Open Derivatives	The gross notional volume of open derivatives is as follows: September 30, 2015 December 31, 2014 Commodity derivative contracts 343,560 MWh 448,000 MWh Commodity derivative contracts 6,547,500 Dth 4,405,000 Dth FTRs 3,286 MW 1,854 MW
Fair Value of Derivative Instruments on the Balance Sheet	The following table summarizes the fair value of the derivative instruments on the consolidated balance sheet s . All derivative in struments in this table are presented on a gross basis and are calculated prior to the netting of instruments with the same counterparty under a master netting agreement as well as the netting of collateral. For financial statement purposes, MGE Energy and MGE have netted instruments with the same counterparty under a master netting agreement as well as the netting of collateral. At September 30, 2015 , MGE Energy and MGE had the right to reclaim collateral (a receivable) of $ 0.8 million . Asset Derivatives Liability Derivatives (In thousands) Balance Sheet Location Fair Value Balance Sheet Location Fair Value September 30, 2015 Commodity derivative contracts Other current assets $ 375 Derivative liability (current) $ 1,196 Commodity derivative contracts Other deferred charges 65 Derivative liability (long-term) 62 FTRs Other current assets 370 Derivative liability (current) - PPA N/A N/A Derivative liability (current) 8,880 PPA N/A N/A Derivative liability (long-term) 48,070 December 31, 2014 Commodity derivative contracts Other current assets $ 130 Derivative liability (current) $ 2,262 Commodity derivative contracts Other deferred charges 93 Derivative liability (long-term) 171 FTRs Other current assets 642 Derivative liability (current) - PPA N/A N/A Derivative liability (current) 6,870 PPA N/A N/A Derivative liability (long-term) 46,560
Offsetting Assets	The foll owing tables show the ef fect of netting arrangements for recognized derivative assets and liabilities that are subject to a master netting arr angement or similar arrangement on the consolidated balance sheets . Offsetting of Derivative Assets (In thousands) Gross amounts Gross amounts offset in balance sheet Collateral posted against derivative positions Net amount presented in balance sheet September 30, 2015 Commodity derivative contracts $ 440 $ (431) $ - $ 9 FTRs 370 - - 370 December 31, 2014 Commodity derivative contracts $ 223 $ (223) $ - $ - FTRs 642 - - 642
Offsetting Liabilities	Offsetting of Derivative Liabilities (In thousands) Gross amounts Gross amounts offset in balance sheet Collateral posted against derivative positions Net amount presented in balance sheet September 30, 2015 Commodity derivative contracts $ 1,258 $ (431) $ (827) $ - PPA 56,950 - - 56,950 December 31, 2014 Commodity derivative contracts $ 2,433 $ (223) $ (2,179) $ 31 PPA 53,430 - - 53,430
Derivative Gains and Losses in Balance Sheet	The following table s summarize the unrealized and realized gains (losses) related to the derivative instruments on the consolidated balance sheet s at September 30, 2015 and 2014 , and the consolidated income statement s for the three and nine months ended September 30, 2015 and 2014 . 2015 2014 (In thousands) Current and long-term regulatory asset Other current assets Current and long-term regulatory asset Other current assets Three Months Ended September 30: Balance at July 1, $ 56,048 $ 455 $ 48,853 $ 676 Unrealized loss (gain) 4,036 - 5,329 - Realized (loss) gain reclassified to a deferred account (408) 408 (314) 314 Realized (loss) gain reclassified to income statement (2,278) (91) (1,184) (249) Balance at September 30, $ 57,398 $ 772 $ 52,684 $ 741 Nine Months Ended September 30: Balance at January 1, $ 54,998 $ 1,001 $ 63,893 $ 411 Unrealized loss (gain) 8,514 - (18,090) - Realized (loss) gain reclassified to a deferred account (1,700) 1,700 1,120 (1,120) Realized (loss) gain reclassified to income statement (4,414) (1,929) 5,761 1,450 Balance at September 30, $ 57,398 $ 772 $ 52,684 $ 741
Derivative Gains and Losses in Income Statement	Realized losses (gains) 2015 2014 (In thousands) Fuel for electric generation/ purchased power Cost of gas sold Fuel for electric generation/ purchased power Cost of gas sold Three Months Ended September 30: Commodity derivative contracts $ 862 $ (17) $ 480 $ (18) FTRs (233) - (97) - PPA 1,757 - 1,068 - Nine Months Ended September 30: Commodity derivative contracts $ 1,860 $ 1,742 $ (5,376) $ (1,367) FTRs (607) - (929) - PPA 3,348 - 461 -

Fair Value of Financial Instr33

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Estimated Fair Market Value of Financial Instruments	The estimated fair market value of MGE Energy's and MGE's financial instruments are as follows: September 30, 2015 December 31, 2014 (In thousands) Carrying Amount Fair Value Carrying Amount Fair Value MGE Energy Assets: Cash and cash equivalents $ 94,267 $ 94,267 $ 65,755 $ 65,755 Liabilities: Short-term debt - commercial paper - - 7,000 7,000 Long-term debt* 396,562 446,176 399,690 457,420 MGE Assets: Cash and cash equivalents $ 41,971 $ 41,971 $ 4,562 $ 4,562 Liabilities: Short-term debt - commercial paper - - 7,000 7,000 Long-term debt* 396,562 446,176 399,690 457,420 *Includes long-term debt due within one year.
Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table presents the balances of assets and liabilities measured at fair value on a recurring basis for MGE Energy and MGE. Fair Value as of September 30, 2015 (In thousands) Total Level 1 Level 2 Level 3 MGE Energy Assets: Derivatives, net $ 379 $ - $ - $ 379 Exchange-traded investments 627 627 - - Total Assets $ 1,006 $ 627 $ - $ 379 Liabilities: Derivatives, net (a) $ 57,777 $ 316 $ - $ 57,461 Deferred compensation 3,160 - 3,160 - Total Liabilities $ 60,937 $ 316 $ 3,160 $ 57,461 MGE Assets: Derivatives, net $ 379 $ - $ - $ 379 Exchange-traded investments 122 122 - - Total Assets $ 501 $ 122 $ - $ 379 Liabilities: Derivatives, net (a) $ 57,777 $ 316 $ - $ 57,461 Deferred compensation 3,160 - 3,160 - Total Liabilities $ 60,937 $ 316 $ 3,160 $ 57,461 Fair Value as of December 31, 2014 (In thousands) Total Level 1 Level 2 Level 3 MGE Energy Assets: Derivatives, net $ 642 $ - $ - $ 642 Exchange-traded investments 927 927 - - Total Assets $ 1,569 $ 927 $ - $ 642 Liabilities: Derivatives, net (a) $ 55,640 $ 1,012 $ - $ 54,628 Deferred compensation 2,832 - 2,832 - Total Liabilities $ 58,472 $ 1,012 $ 2,832 $ 54,628 MGE Assets: Derivatives, net $ 642 $ - $ - $ 642 Exchange-traded investments 350 350 - - Total Assets $ 992 $ 350 $ - $ 642 Liabilities: Derivatives, net (a) $ 55,640 $ 1,012 $ - $ 54,628 Deferred compensation 2,832 - 2,832 - Total Liabilities $ 58,472 $ 1,012 $ 2,832 $ 54,628 (a) These amounts are shown gross and exclude $0.8 million and $2.2 million of collateral that was posted against derivative positions with counterparties as of September 30, 2015, and December 31, 2014, respectively.
Significant Unobservable Inputs	The following table presents the significant unobservable inputs used in the pricing model. Model Input Significant Unobservable Inputs September 30, 2015 December 31, 2014 Basis adjustment: On peak 97.4 % 98.1 % Off peak 95.4 % 95.0 % Counterparty fuel mix: Internal generation 60% - 75% 50% - 70% Purchased power 40% - 25% 50% - 30%
Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table summarizes the changes in Level 3 assets and liabilities measured at fair value on a recurring basis for both MGE Energy and MGE. Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Beginning balance $ (56,194) $ (49,349) $ (53,986) $ (64,628) Realized and unrealized gains (losses): Included in regulatory liabilities (assets) (888) (3,752) (3,096) 11,528 Included in other comprehensive income - - - - Included in earnings (2,285) (1,419) (4,497) 5,837 Included in current assets - - - (89) Purchases 6,364 6,371 17,497 19,900 Sales - - 34 (60) Issuances - - - - Settlements (4,079) (4,952) (13,034) (25,589) Transfers in and/or out of Level 3 - - - - Balance as of September 30, $ (57,082) $ (53,101) $ (57,082) $ (53,101) Total gains (losses) included in earnings attributed to the change in unrealized gains (losses) related to assets and liabilities held at September 30, (b) $ - $ - $ - $ - (b) MGE's exchange-traded derivative contracts, over-the-counter party transactions, purchased power agreement, and FTRs are subject to regulatory deferral. These derivatives are therefore marked to fair value and are offset in the financial statements with a corresponding regulatory asset or liability.
Gains and Losses Included in Income for Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table presents total realized and unrealized gains (losses) included in income for Level 3 assets and liabilities measured at fair value on a recurring basis for both MGE Energy and MGE ( b ). Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2015 2014 2015 2014 Purchased Power Expense $ (2,302) $ (1,411) $ (4,515) $ 5,845 Cost of Gas Sold Expense 17 (8) 18 (8) Total $ (2,285) $ (1,419) $ (4,497) $ 5,837 (b) MGE's exchange-traded derivative contracts, over-the-counter party transactions, purchased power agreement, and FTRs are subject to regulatory deferral. These derivatives are therefore marked to fair value and are offset in the financial statements with a corresponding regulatory asset or liability.

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment Information	The following table s show segment information for MGE Energy ' s operations for the indicated periods : (In thousands) MGE Energy Electric Gas Non- Regulated Energy Transmission Investment All Others Consolidation/ Elimination Entries Consolidated Total Three Months Ended September 30, 2015 Operating revenues $ 121,453 $ 17,431 $ 1,911 $ - $ - $ - $ 140,795 Interdepartmental revenues 163 3,855 9,866 - - (13,884) - Total operating revenues 121,616 21,286 11,777 - - (13,884) 140,795 Depreciation and amortization (7,584) (1,714) (1,872) - (12) - (11,182) Other operating expenses (80,202) (16,906) (36) (15) (161) 13,884 (83,436) Operating income (loss) 33,830 2,666 9,869 (15) (173) - 46,177 Other (deductions) income, net 141 (7) - 2,397 33 - 2,564 Interest (expense) income, net (2,798) (804) (1,491) - 57 - (5,036) Income (loss) before taxes 31,173 1,855 8,378 2,382 (83) - 43,705 Income tax (provision) benefit (10,321) (732) (3,362) (962) 26 - (15,351) Net income (loss) $ 20,852 $ 1,123 $ 5,016 $ 1,420 $ (57) $ - $ 28,354 Three Months Ended September 30, 2014 Operating revenues $ 112,869 $ 21,404 $ 862 $ - $ - $ - $ 135,135 Interdepartmental revenues 156 1,614 10,674 - - (12,444) - Total operating revenues 113,025 23,018 11,536 - - (12,444) 135,135 Depreciation and amortization (6,931) (1,575) (1,858) - (12) - (10,376) Other operating expenses (74,573) (22,199) (35) - (276) 12,444 (84,639) Operating income (loss) 31,521 (756) 9,643 - (288) - 40,120 Other income, net 136 8 - 2,423 69 - 2,636 Interest (expense) income, net (2,832) (808) (1,545) - 44 - (5,141) Income (loss) before taxes 28,825 (1,556) 8,098 2,423 (175) - 37,615 Income tax (provision) benefit (10,758) 651 (3,251) (963) 35 - (14,286) Net income (loss) $ 18,067 $ (905) $ 4,847 $ 1,460 $ (140) $ - $ 23,329 Nine Months Ended September 30, 2015 Operating revenues $ 319,174 $ 108,028 $ 5,853 $ - $ - $ - $ 433,055 Interdepartmental revenues 400 8,871 29,566 - - (38,837) - Total operating revenues 319,574 116,899 35,419 - - (38,837) 433,055 Depreciation and amortization (22,372) (5,018) (5,601) - (35) - (33,026) Other operating expenses (239,963) (96,063) (122) (15) (626) 38,837 (297,952) Operating income (loss) 57,239 15,818 29,696 (15) (661) - 102,077 Other (deductions) income, net 247 (33) - 6,568 333 - 7,115 Interest (expense) income, net (8,385) (2,398) (4,516) - 164 - (15,135) Income (loss) before taxes 49,101 13,387 25,180 6,553 (164) - 94,057 Income tax (provision) benefit (15,868) (5,370) (10,106) (2,637) 35 - (33,946) Net income (loss) $ 33,233 $ 8,017 $ 15,074 $ 3,916 $ (129) $ - $ 60,111 Nine Months Ended September 30, 2014 Operating revenues $ 308,418 $ 163,335 $ 2,392 $ - $ - $ - $ 474,145 Interdepartmental revenues 401 7,130 32,017 - - (39,548) - Total operating revenues 308,819 170,465 34,409 - - (39,548) 474,145 Depreciation and amortization (19,909) (4,700) (5,547) - (35) - (30,191) Other operating expenses (229,286) (144,907) (105) - (672) 39,548 (335,422) Operating income (loss) 59,624 20,858 28,757 - (707) - 108,532 Other (deductions) income, net 2,999 (44) - 7,306 475 - 10,736 Interest (expense) income, net (7,571) (2,429) (4,676) - 126 - (14,550) Income (loss) before taxes 55,052 18,385 24,081 7,306 (106) - 104,718 Income tax provision (19,602) (7,378) (9,665) (2,924) (16) - (39,585) Net income (loss) $ 35,450 $ 11,007 $ 14,416 $ 4,382 $ (122) $ - $ 65,133 The following table s show segment information for MGE ' s operations for the indicated periods : (In thousands) MGE Electric Gas Non- Regulated Energy Transmission Investment Consolidation/ Elimination Entries Consolidated Total Three Months Ended September 30, 2015 Operating revenues $ 121,460 $ 17,435 $ 1,911 $ - $ - $ 140,806 Interdepartmental revenues 156 3,851 9,866 - (13,873) - Total operating revenues 121,616 21,286 11,777 - (13,873) 140,806 Depreciation and amortization (7,584) (1,714) (1,872) - - (11,170) Other operating expenses* (90,511) (17,635) (3,398) (15) 13,873 (97,686) Operating income (loss)* 23,521 1,937 6,507 (15) - 31,950 Other (deductions) income, net* 129 (10) - 1,435 - 1,554 Interest expense, net (2,798) (804) (1,491) - - (5,093) Net income 20,852 1,123 5,016 1,420 - 28,411 Less: Net income attributable to noncontrolling interest, net of tax - - - - (6,633) (6,633) Net income attributable to MGE $ 20,852 $ 1,123 $ 5,016 $ 1,420 $ (6,633) $ 21,778 Three Months Ended September 30, 2014 Operating revenues $ 112,875 $ 21,410 $ 862 $ - $ - $ 135,147 Interdepartmental revenues 150 1,608 10,674 - (12,432) - Total operating revenues 113,025 23,018 11,536 - (12,432) 135,147 Depreciation and amortization (6,931) (1,575) (1,858) - - (10,364) Other operating expenses* (85,314) (21,544) (3,286) - 12,432 (97,712) Operating income (loss)* 20,780 (101) 6,392 - - 27,071 Other income, net* 119 4 - 1,460 - 1,583 Interest expense, net (2,832) (808) (1,545) - - (5,185) Net income (loss) 18,067 (905) 4,847 1,460 - 23,469 Less: Net income attributable to noncontrolling interest, net of tax - - - - (6,653) (6,653) Net income (loss) attributable to MGE $ 18,067 $ (905) $ 4,847 $ 1,460 $ (6,653) $ 16,816 Nine Months Ended September 30, 2015 Operating revenues $ 319,191 $ 108,039 $ 5,853 $ - $ - $ 433,083 Interdepartmental revenues 383 8,860 29,566 - (38,809) - Total operating revenues 319,574 116,899 35,419 - (38,809) 433,083 Depreciation and amortization (22,372) (5,018) (5,601) - - (32,991) Other operating expenses* (255,732) (101,405) (10,228) (15) 38,809 (328,571) Operating income (loss)* 41,470 10,476 19,590 (15) - 71,521 Other (deductions) income, net* 148 (61) - 3,931 - 4,018 Interest expense, net (8,385) (2,398) (4,516) - - (15,299) Net income 33,233 8,017 15,074 3,916 - 60,240 Less: Net income attributable to noncontrolling interest, net of tax - - - - (19,812) (19,812) Net income attributable to MGE $ 33,233 $ 8,017 $ 15,074 $ 3,916 $ (19,812) $ 40,428 Nine Months Ended September 30, 2014 Operating revenues $ 308,435 $ 163,351 $ 2,392 $ - $ - $ 474,178 Interdepartmental revenues 384 7,114 32,017 - (39,515) - Total operating revenues 308,819 170,465 34,409 - (39,515) 474,178 Depreciation and amortization (19,909) (4,700) (5,547) - - (30,156) Other operating expenses* (248,525) (152,182) (9,770) - 39,515 (370,962) Operating income (loss)* 40,385 13,583 19,092 - - 73,060 Other (deductions) income, net* 2,636 (147) - 4,382 - 6,871 Interest expense, net (7,571) (2,429) (4,676) - - (14,676) Net income 35,450 11,007 14,416 4,382 - 65,255 Less: Net income attributable to noncontrolling interest, net of tax - - - - (19,784) (19,784) Net income attributable to MGE $ 35,450 $ 11,007 $ 14,416 $ 4,382 $ (19,784) $ 45,471 *Amounts are shown net of the related tax expense, consistent with the presentation on the MGE Consolidated Statement of Income.

Equity and Financing Arrangem35

Equity and Financing Arrangements (Details) - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Common Stock [Abstract]
Common stock issued during period	0	0
Dilutive Shares Calculation [Abstract]
Dilutive securities	$ 0
MGE [Member]
Credit Facilities [Line Items]
Commercial paper outstanding	0
MGE [Member] | MGE $60 million unsecured committed revolving line of credit
Credit Facilities [Line Items]
Available lines of credit	60,000,000
Line of credit, borrowings outstanding	$ 0
Line Of Credit Facility Fixed Base Rate For Federal Funds	0.50%
Line Of Credit Facility Fixed Base Rate For Eurodollar Rate	1.00%
MGE [Member] | MGE $60 million unsecured committed revolving line of credit | Minimum [Member]
Credit Facilities [Line Items]
Line Of Credit Facility Floating Rate Based Adder	0.00%
Line Of Credit Facility Eurodollar Based Adder	0.625%
MGE [Member] | MGE $60 million unsecured committed revolving line of credit | Maximum [Member]
Credit Facilities [Line Items]
Line Of Credit Facility Floating Rate Based Adder	0.125%
Line Of Credit Facility Eurodollar Based Adder	1.125%
MGE [Member] | MGE $40 million unsecured committed revolving line of credit
Credit Facilities [Line Items]
Available lines of credit	$ 40,000,000
Line of credit, borrowings outstanding	$ 0
Line Of Credit Facility Fixed Base Rate For Federal Funds	0.50%
Line Of Credit Facility Fixed Base Rate For Eurodollar Rate	1.00%
MGE [Member] | MGE $40 million unsecured committed revolving line of credit | Minimum [Member]
Credit Facilities [Line Items]
Line Of Credit Facility Floating Rate Based Adder	0.00%
Line Of Credit Facility Eurodollar Based Adder	0.625%
MGE [Member] | MGE $40 million unsecured committed revolving line of credit | Maximum [Member]
Credit Facilities [Line Items]
Line Of Credit Facility Floating Rate Based Adder	0.125%
Line Of Credit Facility Eurodollar Based Adder	1.125%
MGE Energy [Member] | MGE Energy $50 million unsecured commiteed revolving line of credit
Credit Facilities [Line Items]
Available lines of credit	$ 50,000,000
Line of credit, borrowings outstanding	$ 0
Line Of Credit Facility Fixed Base Rate For Federal Funds	0.50%
Line Of Credit Facility Fixed Base Rate For Eurodollar Rate	1.00%
MGE Energy [Member] | MGE Energy $50 million unsecured commiteed revolving line of credit | Minimum [Member]
Credit Facilities [Line Items]
Line Of Credit Facility Floating Rate Based Adder	0.00%
Line Of Credit Facility Eurodollar Based Adder	0.625%
MGE Energy [Member] | MGE Energy $50 million unsecured commiteed revolving line of credit | Maximum [Member]
Credit Facilities [Line Items]
Line Of Credit Facility Floating Rate Based Adder	0.125%
Line Of Credit Facility Eurodollar Based Adder	1.125%

Investment in ATC (Details-1)

Investment in ATC (Details-1) - USD ($) $ in Thousands	Oct. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Schedule Of Equity Method Investments [Line Items]
Equity earnings from investment		$ 6,568	$ 7,306
Dividend income from investment		4,732	5,762
Capital contributions to investment		785	1,830
MGE Transco [Member] | ATC [Member]
Schedule Of Equity Method Investments [Line Items]
Equity earnings from investment		6,568	7,306
Dividend income from investment		4,732	5,762
Capital contributions to investment		533	$ 1,420
Equity method investment		$ 70,000		$ 67,700
MGE Transco [Member] | ATC [Member] | Subsequent Event [Member]
Schedule Of Equity Method Investments [Line Items]
Capital contributions to investment	$ 200

Investment in ATC (Details-2)

Investment in ATC (Details-2) - ATC [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Schedule Of Equity Method Investments [Line Items]
Operating revenues	$ 164,515	$ 163,643	$ 482,043	$ 486,970
Operating expenses	(78,059)	(76,561)	(238,336)	(229,589)
Other income (expense), net	585	693	566	1,403
Interest expense, net	(23,655)	(22,204)	(72,310)	(66,442)
Earnings before members' income taxes	$ 63,386	$ 65,571	$ 171,963	$ 192,342

Chattel Paper Agreements (Detai

Chattel Paper Agreements (Details-1) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Cumulative effect of new accounting guidance, retained earnings		$ (142)
Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreement, maximum exposure	$ 10,000
Repurchase-to-Maturity Transactions, loans due	3,806
Cumulative effect of new accounting guidance, retained earnings		$ (100)
2015 [Member] | Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase-to-Maturity Transactions, loans due	132
2016 [Member] | Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase-to-Maturity Transactions, loans due	735
2017 [Member] | Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase-to-Maturity Transactions, loans due	472
2018 [Member] | Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase-to-Maturity Transactions, loans due	504
Thereafter [Member] | Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase-to-Maturity Transactions, loans due	$ 1,963
Minimum [Member] | Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
MGE guarantee to the financial institution, term	1 year
Maximum [Member] | Chattel Paper Agreements [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
MGE guarantee to the financial institution, term	10 years

Taxes (Details)

Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Line Items]
Effective income tax rate	35.10%	38.00%	36.10%	37.80%
MGE [Member]
Income Tax Disclosure [Line Items]
Effective income tax rate	35.10%	37.90%	36.10%	37.80%

Pension and Other Postretirem40

Pension and Other Postretirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pension Benefits [Member]
Components of net periodic cost (benefit):
Service cost	$ 1,878	$ 1,536	$ 5,715	$ 4,609
Interest cost	3,594	3,367	10,936	10,102
Expected return on assets	(5,930)	(5,467)	(18,045)	(16,402)
Amortization of:
Prior service (benefit) cost	6	51	18	152
Actuarial loss	1,393	180	4,240	539
Net periodic cost (benefit)	941	(333)	2,864	(1,000)
Postretirement Benefits [Member]
Components of net periodic cost (benefit):
Service cost	194	241	580	722
Interest cost	392	564	1,176	1,691
Expected return on assets	(355)	(478)	(1,063)	(1,432)
Amortization of:
Transition obligation	0	1	1	2
Prior service (benefit) cost	(337)	(487)	(1,009)	(1,462)
Actuarial loss	133	28	397	86
Net periodic cost (benefit)	$ 27	$ (131)	$ 82	$ (393)

Share Based Compensation (Detai

Share Based Compensation (Details) - Performance Units [Member] - USD ($) $ in Millions	Feb. 20, 2015	Jan. 31, 2015	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense			$ 0.4	$ 0.9
Cash payments distributed related to awards previously granted and now payable		$ 1.3
Awards forfeited during period, value			$ 0.2	$ 0
Awards forfeited during period, units			4,676	0
Outstanding awards vested during period			$ 4.2
Performance Unit Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted during period (in units)	18,948
Award vesting period			5 years
Director Incentive Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted during period (in units)		3,794
Award vesting period			3 years

Commitments and Contingencies42

Commitments and Contingencies (Details-1) $ in Millions	9 Months Ended
	Sep. 30, 2015USD ($)TonsppbMW
Columbia Environmental Project, SCR [Member] | MGE [Member]
Columbia Commitments
Share of projected project cost, minimum | $	$ 19
Share of projected project cost, maximum | $	$ 29
EPA [Member] | Legal Entity Type of Counterparty [Domain]
Effluent Limitations Guidelines and Standards for Steam Electric Power Generating Source Category [Abstract]
Air pollution control and ash handling systems capacity at coal burning power plants, minimum (in MW) | MW	50
EPA's Greenhouse Gas Reduction Guidelines
National average reduction of greenhouse gas emissions by the year 2030, percentage	32.00%
Compliance plan preparation term related to the greenhouse gas emissions reduction guidelines	3 years
Sulfur Dioxide NAAQS
Annual maximum level of sulfur dioxide for large stationary sources | Tons	2,000
Ozone NAAQS
Current primary regulated level of Ozone NAAQS (in parts per billion)	70
Current secondary regulated level of Ozone NAAQS (in parts per billion)	70

Commitments and Contingencies43

Commitments and Contingencies (Details-2) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Operating expense purchase contracts [Abstract]
Purchase obligation, 2015	$ 22,144
Purchase obligation, 2016	50,883
Purchase obligation, 2017	28,647
Purchase obligation, 2018	24,461
Purchase obligation, 2019	20,821
Coal [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2015	6,211	[1]
Purchase obligation, 2016	21,639	[1]
Purchase obligation, 2017	10,664	[1]
Purchase obligation, 2018	6,560	[1]
Purchase obligation, 2019	3,850	[1]
Natural Gas, Transportation and Storage [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2015	5,229	[2]
Purchase obligation, 2016	18,117	[2]
Purchase obligation, 2017	17,983	[2]
Purchase obligation, 2018	17,901	[2]
Purchase obligation, 2019	16,971	[2]
Natual Gas, Supply [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2015	10,704	[3]
Purchase obligation, 2016	11,127	[3]
Purchase obligation, 2017	0	[3]
Purchase obligation, 2018	0	[3]
Purchase obligation, 2019	0	[3]
Columbia Asset Retirement Obligation - Coal Combustion Residual Rule [Member]
Asset Retirement Obligation [Line Items]
Liabilities incurred	$ 2,300
[1]	Total coal commitments for the Columbia and Elm Road Units, including transportation. Fuel procurement for MGE's jointly owned Columbia and Elm Road Units is handled by WPL and WEPCO, respectively, who are the operators of those facilities. If any minimum purchase obligations must be paid under these contracts, management believes these obligations would be considered costs of service and recoverable in rates.
[2]	MGE's natural gas transportation and storage contracts require fixed monthly payments for firm supply pipeline transportation and storage capacity. The pricing components of the fixed monthly payments for the transportation and storage contracts are established by FERC but may be subject to change.
[3]	These commitments include market-bas ed pricing. Management expects to recover these costs in future customer rates.

Derivative and Hedging Instru44

Derivative and Hedging Instruments (Details-1) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015USD ($)DthMWhMW	Dec. 31, 2014USD ($)DthMWhMW	Jun. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Jun. 30, 2014USD ($)	Dec. 31, 2013USD ($)
Gross Notional Volume of Open Derivatives
Derivative, right to reclaim collateral (receivable)	$ 800
Other Current Assets [Member]
Derivative fair values [Abstract]
Derivative fair value, net	772	$ 1,001	$ 455	$ 741	$ 676	$ 411
Commodity Contracts And Financial Transimission Rights [Member]
Derivative fair values [Abstract]
Derivative fair value, net	$ (400)	$ (1,600)
Commodity Derivative Contracts [Member]
Gross Notional Volume of Open Derivatives
Notional amount, energy measure (in MWh) | MWh	343,560	448,000
Notional amount, decatherm measure (in Dth) | Dth	6,547,500	4,405,000
Derivative fair values [Abstract]
Asset Derivatives, fair value, gross basis	$ 440	$ 223
Liability Derivatives, fair value, gross basis	1,258	2,433
Commodity Derivative Contracts [Member] | Other Current Assets [Member]
Derivative fair values [Abstract]
Asset Derivatives, fair value, gross basis	375	130
Commodity Derivative Contracts [Member] | Other Deferred Charges [Member]
Derivative fair values [Abstract]
Asset Derivatives, fair value, gross basis	65	93
Commodity Derivative Contracts [Member] | Derivative Liability (Current) [Member]
Derivative fair values [Abstract]
Liability Derivatives, fair value, gross basis	1,196	2,262
Commodity Derivative Contracts [Member] | Derivative Liability (Long-term) [Member]
Derivative fair values [Abstract]
Liability Derivatives, fair value, gross basis	$ 62	$ 171
Energy Related Commodity Contract [Member] | Cash Flow Hedging [Member]
Derivatives Fair Value [Line Items]
Maximum term of derivative hedging contract	4 years
Financial Transmission Rights [Member]
Gross Notional Volume of Open Derivatives
Notional amount, power measure (in MW) | MW	3,286	1,854
Derivative fair values [Abstract]
Asset Derivatives, fair value, gross basis	$ 370	$ 642
Financial Transmission Rights [Member] | Other Current Assets [Member]
Derivative fair values [Abstract]
Asset Derivatives, fair value, gross basis	370	642
Financial Transmission Rights [Member] | Derivative Liability (Current) [Member]
Derivative fair values [Abstract]
Liability Derivatives, fair value, gross basis	0	0
PPA [Member]
Derivative fair values [Abstract]
Derivative fair value, net	(57,000)	(53,400)
Liability Derivatives, fair value, gross basis	56,950	53,430
PPA [Member] | Derivative Liability (Current) [Member]
Derivative fair values [Abstract]
Liability Derivatives, fair value, gross basis	8,880	6,870
PPA [Member] | Derivative Liability (Long-term) [Member]
Derivative fair values [Abstract]
Liability Derivatives, fair value, gross basis	$ 48,070	$ 46,560

Derivative and Hedging Instru45

Derivative and Hedging Instruments (Details-2) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Commodity Derivative Contracts [Member]
Offsetting Assets [Line Items]
Gross amounts	$ 440	$ 223
Gross amounts offset in balance sheet	(431)	(223)
Collateral posted against derivative positions	0	0
Net amount presented in balance sheet	9	0
Financial Transmission Rights [Member]
Offsetting Assets [Line Items]
Gross amounts	370	642
Gross amounts offset in balance sheet	0	0
Collateral posted against derivative positions	0	0
Net amount presented in balance sheet	$ 370	$ 642

Derivative and Hedging Instru46

Derivative and Hedging Instruments (Details-3) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Offsetting Liabilities [Line Items]
Collateral posted against derivative positions	$ (800)	$ (2,200)
Commodity Derivative Contracts [Member]
Offsetting Liabilities [Line Items]
Gross amounts	1,258	2,433
Gross amounts offset in balance sheet	(431)	(223)
Collateral posted against derivative positions	(827)	(2,179)
Net amount presented in balance sheet	0	31
Purchased Power Agreement [Member]
Offsetting Liabilities [Line Items]
Gross amounts	56,950	53,430
Gross amounts offset in balance sheet	0	0
Collateral posted against derivative positions	0	0
Net amount presented in balance sheet	$ 56,950	$ 53,430

Derivative and Hedging Instru47

Derivative and Hedging Instruments (Details-4) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Regulatory Asset [Member]
Change In Derivative Fair Value [Roll Forward]
Beginning balance,	$ 56,048	$ 48,853	$ 54,998	$ 63,893
Unrealized loss (gain)	4,036	5,329	8,514	(18,090)
Realized gain (loss) reclassified to a deferred account	(408)	(314)	(1,700)	1,120
Realized gain (loss) reclassified to income statement	(2,278)	(1,184)	(4,414)	5,761
Ending balance,	57,398	52,684	57,398	52,684
Other Current Assets [Member]
Change In Derivative Fair Value [Roll Forward]
Beginning balance,	455	676	1,001	411
Unrealized loss (gain)	0	0	0	0
Realized gain (loss) reclassified to a deferred account	408	314	1,700	(1,120)
Realized gain (loss) reclassified to income statement	(91)	(249)	(1,929)	1,450
Ending balance,	$ 772	$ 741	$ 772	$ 741

Derivative and Hedging Instru48

Derivative and Hedging Instruments (Details-5) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015USD ($)counterparty	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)counterparty	Sep. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Counterparties in net liability position or default [Abstract]
Derivative, net liability position of counterparties (less than $0.1 million)	$ 100		$ 100		$ 100
Number of counterparties in default | counterparty	0		0
Commodity Derivative Contracts [Member] | Fuel For Electric Generation Purchased Power [Member]
Realized losses (gains) on income statement [Line Items]
Realized losses (gains) on income statement	$ 862	$ 480	$ 1,860	$ (5,376)
Commodity Derivative Contracts [Member] | Cost Of Gas Sold Expense [Member]
Realized losses (gains) on income statement [Line Items]
Realized losses (gains) on income statement	(17)	(18)	1,742	(1,367)
Financial Transmission Rights [Member] | Fuel For Electric Generation Purchased Power [Member]
Realized losses (gains) on income statement [Line Items]
Realized losses (gains) on income statement	(233)	(97)	(607)	(929)
Financial Transmission Rights [Member] | Cost Of Gas Sold Expense [Member]
Realized losses (gains) on income statement [Line Items]
Realized losses (gains) on income statement	0	0	0	0
Purchased Power Agreement [Member]
Derivative collateral required to be posted for PPA [Abstract]
Minimum collateral that may be required to be posted	20,000		20,000
Maximum collateral that may be required to be posted	40,000		40,000
Collateral posted	0		0
Purchased Power Agreement [Member] | Fuel For Electric Generation Purchased Power [Member]
Realized losses (gains) on income statement [Line Items]
Realized losses (gains) on income statement	1,757	1,068	3,348	461
Purchased Power Agreement [Member] | Cost Of Gas Sold Expense [Member]
Realized losses (gains) on income statement [Line Items]
Realized losses (gains) on income statement	$ 0	$ 0	$ 0	$ 0

Rate Matters (Details)

Rate Matters (Details) - USD ($) $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Aug. 31, 2015
MGE [Member]
Purchased Gas Adjustment [Abstract]
Purchased gas adjustment, overcollection	$ 1.1		$ 1.2
PSCW [Member] | Legal Entity Type of Counterparty [Domain]
Fuel Rules [Abstract]
Fuel rules, bandwidth	2.00%
Fuel rules, electric fuel deferred costs upper threshold	102.00%
Fuel rules, electric fuel deferred costs lower threshold	98.00%
PSCW [Member] | MGE [Member]
Rate Proceedings [Abstract]
Authorized return on equity, percentage	10.20%		10.30%
PSCW [Member] | MGE [Member] | Fuel Rules Surplus Credit, 2012 [Member]
Rate Proceedings [Abstract]
Return of electric fuel credit, total			$ 6.3
Fuel Rules [Abstract]
Return of electric fuel credit, current period		$ 4.7
PSCW [Member] | MGE [Member] | Fuel Rules Surplus Credit, 2015 [Member]
Fuel Rules [Abstract]
Fuel rules, deferred electric cost	$ 7.6
Return of electric fuel credit, current period	$ 0.7
PSCW [Member] | Total Estimated 2015 Fuel Rules Credit, 2015 [Member] | MGE [Member] | Subsequent Event [Member]
Rate Proceedings [Abstract]
Public Utilities Return Of Fuel Rules Surplus Credit Future Period				$ 5.9
PSCW [Member] | Estimated Return of 2015 Fuel Rules Credit During 2015 [Member] | MGE [Member] | Subsequent Event [Member]
Rate Proceedings [Abstract]
Public Utilities Return Of Fuel Rules Surplus Credit Future Period				2.7
PSCW [Member] | Estimated 2016 Fuel Rules Credit, 2016 [Member] | MGE [Member] | Subsequent Event [Member]
Rate Proceedings [Abstract]
Public Utilities Return Of Fuel Rules Surplus Credit Future Period				$ 5
PSCW [Member] | Columbia Environmental Project [Member] | MGE [Member]
Rate Proceedings [Abstract]
Authorized AFUDC Rate			100.00%
Electric [Member] | PSCW [Member] | MGE [Member]
Rate Proceedings [Abstract]
Authorized rate increase (decrease), percentage	3.80%		0.00%
Authorized rate increase (decrease), amount	$ 15.4		$ 0
Gas [Member] | PSCW [Member] | MGE [Member]
Rate Proceedings [Abstract]
Authorized rate increase (decrease), percentage	(2.00%)		0.00%
Authorized rate increase (decrease), amount	$ (3.8)		$ 0

Fair Value of Financial Instr50

Fair Value of Financial Instruments (Details-1) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Carrying Amount [Member]
Assets:
Cash and cash equivalents		$ 94,267	$ 65,755
Liabilities:
Short-term debt - commercial paper		0	7,000
Long-term debt	[1]	396,562	399,690
Fair Value [Member]
Assets:
Cash and cash equivalents		94,267	65,755
Liabilities:
Short-term debt - commercial paper		0	7,000
Long-term debt	[1]	446,176	457,420
MGE [Member] | Carrying Amount [Member]
Assets:
Cash and cash equivalents		41,971	4,562
Liabilities:
Short-term debt - commercial paper		0	7,000
Long-term debt	[1]	396,562	399,690
MGE [Member] | Fair Value [Member]
Assets:
Cash and cash equivalents		41,971	4,562
Liabilities:
Short-term debt - commercial paper		0	7,000
Long-term debt	[1]	$ 446,176	$ 457,420
[1]	*Includes long-term debt due within one year.

Fair Value of Financial Instr51

Fair Value of Financial Instruments (Details-2) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Liabilities:
Derivative liability, collateral offset		$ 800	$ 2,200
Recurring [Member]
Assets:
Derivative assets, net		379	642
Total Assets		1,006	1,569
Liabilities:
Derivative liabilities, net	[1]	57,777	55,640
Deferred compensation		3,160	2,832
Total liabilities		60,937	58,472
Recurring [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		627	927
Recurring [Member] | Level 1 [Member]
Assets:
Derivative assets, net		0	0
Total Assets		627	927
Liabilities:
Derivative liabilities, net	[1]	316	1,012
Deferred compensation		0	0
Total liabilities		316	1,012
Recurring [Member] | Level 1 [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		627	927
Recurring [Member] | Level 2 [Member]
Assets:
Derivative assets, net		0	0
Total Assets		0	0
Liabilities:
Derivative liabilities, net	[1]	0	0
Deferred compensation		3,160	2,832
Total liabilities		3,160	2,832
Recurring [Member] | Level 2 [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		0	0
Recurring [Member] | Level 3 [Member]
Assets:
Derivative assets, net		379	642
Total Assets		379	642
Liabilities:
Derivative liabilities, net	[1]	57,461	54,628
Deferred compensation		0	0
Total liabilities		57,461	54,628
Recurring [Member] | Level 3 [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		0	0
MGE [Member]
Liabilities:
Derivative liability, collateral offset		800	2,200
MGE [Member] | Recurring [Member]
Assets:
Derivative assets, net		379	642
Total Assets		501	992
Liabilities:
Derivative liabilities, net	[1]	57,777	55,640
Deferred compensation		3,160	2,832
Total liabilities		60,937	58,472
MGE [Member] | Recurring [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		122	350
MGE [Member] | Recurring [Member] | Level 1 [Member]
Assets:
Derivative assets, net		0	0
Total Assets		122	350
Liabilities:
Derivative liabilities, net	[1]	316	1,012
Deferred compensation		0	0
Total liabilities		316	1,012
MGE [Member] | Recurring [Member] | Level 1 [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		122	350
MGE [Member] | Recurring [Member] | Level 2 [Member]
Assets:
Derivative assets, net		0	0
Total Assets		0	0
Liabilities:
Derivative liabilities, net	[1]	0	0
Deferred compensation		3,160	2,832
Total liabilities		3,160	2,832
MGE [Member] | Recurring [Member] | Level 2 [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		0	0
MGE [Member] | Recurring [Member] | Level 3 [Member]
Assets:
Derivative assets, net		379	642
Total Assets		379	642
Liabilities:
Derivative liabilities, net	[1]	57,461	54,628
Deferred compensation		0	0
Total liabilities		57,461	54,628
MGE [Member] | Recurring [Member] | Level 3 [Member] | Exchange Traded [Member]
Assets:
Available-for-sale securities		$ 0	$ 0
[1]	These amounts are shown gross and exclude $0.8 million and $2.2 million of collateral that was posted against derivative positions with counterparties as of September 30, 2015 and December 31, 2014, respectively.

Fair Value of Financial Instr52

Fair Value of Financial Instruments (Details-3)	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Fair Value Inputs Assets Quantitative Information [Line Items]
Basis adjustment - on peak	97.40%	98.10%
Basis adjustment - off peak	95.40%	95.00%
US Treasury Bill Securities [Member]
Deferred compensation plan [Abstract]
Investment interest calculation, investment maturity period (26 weeks)	182 days
Investment interest calculation, monthly compounding rate	1.00%
Investment interest calculation, minimum annual rate compounded monthly	7.00%
Minimum [Member]
Counterparty fuel mix [Abstract]
Internal generation	60.00%	50.00%
Purchased power	40.00%	50.00%
Maximum [Member]
Counterparty fuel mix [Abstract]
Internal generation	75.00%	70.00%
Purchased power	25.00%	30.00%

Fair Value of Financial Instr53

Fair Value of Financial Instruments (Details-4) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance,		$ (56,194)	$ (49,349)	$ (53,986)	$ (64,628)
Realized and unrealized gains (losses):
Included in regulatory liabilities (assets)		(888)	(3,752)	(3,096)	11,528
Included in other comprehensive income		0	0	0	0
Included in earnings	[1]	(2,285)	(1,419)	(4,497)	5,837
Included in current assets		0	0	0	(89)
Purchases		6,364	6,371	17,497	19,900
Sales		0	0	34	(60)
Issuances		0	0	0	0
Settlements		(4,079)	(4,952)	(13,034)	(25,589)
Transfers in and/or out of level 3		0	0	0	0
Ending balance,		(57,082)	(53,101)	(57,082)	(53,101)
Total gains (losses) included in earnings attributed to the change in unrealized gains (losses) related to assets and liabilities	[1]	0	0	0	0
Purchased Power Expense [Member]
Realized and unrealized gains (losses):
Included in earnings	[1]	(2,302)	(1,411)	(4,515)	5,845
Cost Of Gas Sold Expense [Member]
Realized and unrealized gains (losses):
Included in earnings	[1]	$ 17	$ (8)	$ 18	$ (8)
[1]	MGE's exchange-traded derivative contracts, over-the-counter party transactions, purchased power agreement, and FTRs are subject to regulatory deferral. These derivatives are therefore marked to fair value and are offset in the financial statements with a corresponding regulatory asset or liability.

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Operating revenues		$ 140,795	$ 135,135	$ 433,055	$ 474,145
Depreciation and amortization		(11,182)	(10,376)	(33,026)	(30,191)
Other operating expenses		(83,436)	(84,639)	(297,952)	(335,422)
Operating Income		46,177	40,120	102,077	108,532
Other income (deductions), net		2,564	2,636	7,115	10,736
Interest (expense) income, net		(5,036)	(5,141)	(15,135)	(14,550)
Income before income taxes		43,705	37,615	94,057	104,718
Income tax (provision) benefit		(15,351)	(14,286)	(33,946)	(39,585)
Net Income (Loss)		28,354	23,329	60,111	65,133
Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues		121,453	112,869	319,174	308,418
Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues		17,431	21,404	108,028	163,335
Non Regulated Energy [Member]
Segment Reporting Information [Line Items]
Operating revenues		1,911	862	5,853	2,392
Transmission Investment [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
All Others [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues		140,795	135,135	433,055	474,145
Operating Segments [Member] | Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues		121,616	113,025	319,574	308,819
Depreciation and amortization		(7,584)	(6,931)	(22,372)	(19,909)
Other operating expenses		(80,202)	(74,573)	(239,963)	(229,286)
Operating Income		33,830	31,521	57,239	59,624
Other income (deductions), net		141	136	247	2,999
Interest (expense) income, net		(2,798)	(2,832)	(8,385)	(7,571)
Income before income taxes		31,173	28,825	49,101	55,052
Income tax (provision) benefit		(10,321)	(10,758)	(15,868)	(19,602)
Net Income (Loss)		20,852	18,067	33,233	35,450
Operating Segments [Member] | Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues		21,286	23,018	116,899	170,465
Depreciation and amortization		(1,714)	(1,575)	(5,018)	(4,700)
Other operating expenses		(16,906)	(22,199)	(96,063)	(144,907)
Operating Income		2,666	(756)	15,818	20,858
Other income (deductions), net		(7)	8	(33)	(44)
Interest (expense) income, net		(804)	(808)	(2,398)	(2,429)
Income before income taxes		1,855	(1,556)	13,387	18,385
Income tax (provision) benefit		(732)	651	(5,370)	(7,378)
Net Income (Loss)		1,123	(905)	8,017	11,007
Operating Segments [Member] | Non Regulated Energy [Member]
Segment Reporting Information [Line Items]
Operating revenues		11,777	11,536	35,419	34,409
Depreciation and amortization		(1,872)	(1,858)	(5,601)	(5,547)
Other operating expenses		(36)	(35)	(122)	(105)
Operating Income		9,869	9,643	29,696	28,757
Other income (deductions), net		0	0	0	0
Interest (expense) income, net		(1,491)	(1,545)	(4,516)	(4,676)
Income before income taxes		8,378	8,098	25,180	24,081
Income tax (provision) benefit		(3,362)	(3,251)	(10,106)	(9,665)
Net Income (Loss)		5,016	4,847	15,074	14,416
Operating Segments [Member] | Transmission Investment [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
Depreciation and amortization		0	0	0	0
Other operating expenses		(15)	0	(15)	0
Operating Income		(15)	0	(15)	0
Other income (deductions), net		2,397	2,423	6,568	7,306
Interest (expense) income, net		0	0	0	0
Income before income taxes		2,382	2,423	6,553	7,306
Income tax (provision) benefit		(962)	(963)	(2,637)	(2,924)
Net Income (Loss)		1,420	1,460	3,916	4,382
Operating Segments [Member] | All Others [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
Depreciation and amortization		(12)	(12)	(35)	(35)
Other operating expenses		(161)	(276)	(626)	(672)
Operating Income		(173)	(288)	(661)	(707)
Other income (deductions), net		33	69	333	475
Interest (expense) income, net		57	44	164	126
Income before income taxes		(83)	(175)	(164)	(106)
Income tax (provision) benefit		26	35	35	(16)
Net Income (Loss)		(57)	(140)	(129)	(122)
Consolidation Elimination Entries [Member]
Segment Reporting Information [Line Items]
Operating revenues		(13,884)	(12,444)	(38,837)	(39,548)
Depreciation and amortization		0	0	0	0
Other operating expenses		13,884	12,444	38,837	39,548
Operating Income		0	0	0	0
Other income (deductions), net		0	0	0	0
Interest (expense) income, net		0	0	0	0
Income before income taxes		0	0	0	0
Income tax (provision) benefit		0	0	0	0
Net Income (Loss)		0	0	0	0
Consolidation Elimination Entries [Member] | Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues		163	156	400	401
Consolidation Elimination Entries [Member] | Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues		3,855	1,614	8,871	7,130
Consolidation Elimination Entries [Member] | Non Regulated Energy [Member]
Segment Reporting Information [Line Items]
Operating revenues		9,866	10,674	29,566	32,017
Consolidation Elimination Entries [Member] | Transmission Investment [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
Consolidation Elimination Entries [Member] | All Others [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
MGE [Member]
Segment Reporting Information [Line Items]
Operating revenues		140,806	135,147	433,083	474,178
Depreciation and amortization		(11,170)	(10,364)	(32,991)	(30,156)
Other operating expenses	[1]	(97,686)	(97,712)	(328,571)	(370,962)
Operating Income	[1]	31,950	27,071	71,521	73,060
Other income (deductions), net	[1]	1,554	1,583	4,018	6,871
Interest (expense) income, net		(5,093)	(5,185)	(15,299)	(14,676)
Income tax (provision) benefit		(14,401)	(13,338)	(31,218)	(36,180)
Net Income Including Noncontrolling Interest		28,411	23,469	60,240	65,255
Less Net Income Attributable to Noncontrolling Interest, net of tax		(6,633)	(6,653)	(19,812)	(19,784)
Net Income (Loss)		21,778	16,816	40,428	45,471
MGE [Member] | Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues		121,460	112,875	319,191	308,435
MGE [Member] | Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues		17,435	21,410	108,039	163,351
MGE [Member] | Non Regulated Energy [Member]
Segment Reporting Information [Line Items]
Operating revenues		1,911	862	5,853	2,392
MGE [Member] | Transmission Investment [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
MGE [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues		140,806	135,147	433,083	474,178
MGE [Member] | Operating Segments [Member] | Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues		121,616	113,025	319,574	308,819
Depreciation and amortization		(7,584)	(6,931)	(22,372)	(19,909)
Other operating expenses	[1]	(90,511)	(85,314)	(255,732)	(248,525)
Operating Income	[1]	23,521	20,780	41,470	40,385
Other income (deductions), net	[1]	129	119	148	2,636
Interest (expense) income, net		(2,798)	(2,832)	(8,385)	(7,571)
Net Income Including Noncontrolling Interest		20,852	18,067	33,233	35,450
Less Net Income Attributable to Noncontrolling Interest, net of tax		0	0	0	0
Net Income (Loss)		20,852	18,067	33,233	35,450
MGE [Member] | Operating Segments [Member] | Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues		21,286	23,018	116,899	170,465
Depreciation and amortization		(1,714)	(1,575)	(5,018)	(4,700)
Other operating expenses	[1]	(17,635)	(21,544)	(101,405)	(152,182)
Operating Income	[1]	1,937	(101)	10,476	13,583
Other income (deductions), net	[1]	(10)	4	(61)	(147)
Interest (expense) income, net		(804)	(808)	(2,398)	(2,429)
Net Income Including Noncontrolling Interest		1,123	(905)	8,017	11,007
Less Net Income Attributable to Noncontrolling Interest, net of tax		0	0	0	0
Net Income (Loss)		1,123	(905)	8,017	11,007
MGE [Member] | Operating Segments [Member] | Non Regulated Energy [Member]
Segment Reporting Information [Line Items]
Operating revenues		11,777	11,536	35,419	34,409
Depreciation and amortization		(1,872)	(1,858)	(5,601)	(5,547)
Other operating expenses	[1]	(3,398)	(3,286)	(10,228)	(9,770)
Operating Income	[1]	6,507	6,392	19,590	19,092
Other income (deductions), net	[1]	0	0	0	0
Interest (expense) income, net		(1,491)	(1,545)	(4,516)	(4,676)
Net Income Including Noncontrolling Interest		5,016	4,847	15,074	14,416
Less Net Income Attributable to Noncontrolling Interest, net of tax		0	0	0	0
Net Income (Loss)		5,016	4,847	15,074	14,416
MGE [Member] | Operating Segments [Member] | Transmission Investment [Member]
Segment Reporting Information [Line Items]
Operating revenues		0	0	0	0
Depreciation and amortization		0	0	0	0
Other operating expenses	[1]	(15)	0	(15)	0
Operating Income	[1]	(15)	0	(15)	0
Other income (deductions), net	[1]	1,435	1,460	3,931	4,382
Interest (expense) income, net		0	0	0	0
Net Income Including Noncontrolling Interest		1,420	1,460	3,916	4,382
Less Net Income Attributable to Noncontrolling Interest, net of tax		0	0	0	0
Net Income (Loss)		1,420	1,460	3,916	4,382
MGE [Member] | Consolidation Elimination Entries [Member]
Segment Reporting Information [Line Items]
Operating revenues		(13,873)	(12,432)	(38,809)	(39,515)
Depreciation and amortization		0	0	0	0
Other operating expenses	[1]	13,873	12,432	38,809	39,515
Operating Income	[1]	0	0	0	0
Other income (deductions), net	[1]	0	0	0	0
Interest (expense) income, net		0	0	0	0
Net Income Including Noncontrolling Interest		0	0	0	0
Less Net Income Attributable to Noncontrolling Interest, net of tax		(6,633)	(6,653)	(19,812)	(19,784)
Net Income (Loss)		(6,633)	(6,653)	(19,812)	(19,784)
MGE [Member] | Consolidation Elimination Entries [Member] | Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues		156	150	383	384
MGE [Member] | Consolidation Elimination Entries [Member] | Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues		3,851	1,608	8,860	7,114
MGE [Member] | Consolidation Elimination Entries [Member] | Non Regulated Energy [Member]
Segment Reporting Information [Line Items]
Operating revenues		9,866	10,674	29,566	32,017
MGE [Member] | Consolidation Elimination Entries [Member] | Transmission Investment [Member]
Segment Reporting Information [Line Items]
Operating revenues		$ 0	$ 0	$ 0	$ 0
[1]	*Amounts are shown net of the related tax expense, consistent with the presentation on the MGE Consolidated Statement of Income.