Consolidated Balance Sheets - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents		$ 81,384	$ 65,755
Accounts receivable, less reserves		37,112	41,614
Other accounts receivables, less reserves		7,477	7,610
Unbilled revenues		25,008	31,262
Materials and supplies, at average cost		19,155	17,121
Fossil fuel		13,110	8,098
Stored natural gas, at average cost		16,145	21,036
Prepaid taxes		35,252	38,910
Regulatory assets - current		9,538	8,360
Other current assets		10,570	10,711
Total Current Assets		254,751	250,477
Other long-term receivables		5,045	2,181
Regulatory assets		148,199	156,823
Other deferred assets and other		5,602	4,837
Property, Plant, and Equipment:
Property, plant, and equipment, net		1,217,094	1,189,077
Construction work in progress		26,351	19,029
Total Property, Plant, and Equipment		1,243,445	1,208,106
Investments		73,631	71,760
Total Assets		1,730,673	1,694,184	[1]
Current Liabilities:
Long-term debt due within one year		4,266	4,182
Short-term debt	[2]	0	7,000
Accounts payable		40,830	41,655
Accrued interest and taxes		5,067	5,086
Accrued payroll related items		11,215	11,241
Regulatory liabilities - current		9,515	0
Derivative liabilities		8,343	6,901
Other current liabilities		4,910	13,931
Total Current Liabilities		84,146	89,996
Other Credits:
Deferred income taxes		360,785	338,563	[1]
Investment tax credit - deferred		1,050	1,223
Regulatory liabilities		20,785	22,715
Accrued pension and other postretirement benefits		75,680	90,201
Derivative liabilities		44,935	46,560
Other deferred liabilities and other		61,820	50,269
Total Other Credits		565,055	549,531	[1]
Common shareholders' equity:
Common stock		34,668	34,668
Additional paid-in capital		316,268	316,268
Retained earnings		339,165	308,007
Accumulated other comprehensive income, net of tax		357	458
Total Common Shareholders' Equity		690,458	659,401
Long-term debt		391,014	395,256
Total Capitalization		1,081,472	1,054,657
Commitments and contingencies (see Footnote 18)		0	0
Total Liabilities and Capitalization		1,730,673	1,694,184	[1]
MGE [Member]
Current Assets:
Cash and cash equivalents		26,760	4,562
Accounts receivable, less reserves		37,112	41,614
Affiliate receivables		542	7,112
Other accounts receivables, less reserves		7,390	7,524
Unbilled revenues		25,008	31,262
Materials and supplies, at average cost		19,155	17,121
Fossil fuel		13,110	8,098
Stored natural gas, at average cost		16,145	21,035
Prepaid taxes		34,279	39,103
Regulatory assets - current		9,538	8,360
Other current assets		10,544	10,683
Total Current Assets		199,583	196,474
Affiliate receivable long-term		4,766	5,295
Regulatory assets		148,199	156,823
Other deferred assets and other		8,486	4,977
Property, Plant, and Equipment:
Property, plant, and equipment, net		1,216,415	1,188,351
Construction work in progress		26,351	19,029
Total Property, Plant, and Equipment		1,242,766	1,207,380
Investments		69,984	68,402
Total Assets		1,673,784	1,639,351	[1]
Current Liabilities:
Long-term debt due within one year		4,266	4,182
Short-term debt		0	7,000
Accounts payable		40,742	41,654
Accrued interest and taxes		5,021	5,039
Accrued payroll related items		11,215	11,241
Regulatory liabilities - current		9,515	0
Derivative liabilities		8,343	6,901
Other current liabilities		4,791	11,350
Total Current Liabilities		83,893	87,367
Other Credits:
Deferred income taxes		352,626	333,502	[1]
Investment tax credit - deferred		1,050	1,223
Regulatory liabilities		20,785	22,715
Accrued pension and other postretirement benefits		75,680	90,201
Derivative liabilities		44,935	46,560
Other deferred liabilities and other		61,817	50,267
Total Other Credits		556,893	544,468	[1]
Common shareholders' equity:
Common stock		17,348	17,348
Additional paid-in capital		192,417	192,417
Retained earnings		291,888	276,662
Accumulated other comprehensive income, net of tax		23	144
Total Common Shareholders' Equity		501,676	486,571
Noncontrolling interest		140,308	125,689
Total Equity		641,984	612,260
Long-term debt		391,014	395,256
Total Capitalization		1,032,998	1,007,516
Commitments and contingencies (see Footnote 18)		0	0
Total Liabilities and Capitalization		$ 1,673,784	$ 1,639,351	[1]

[1] Reflects retrospective application of new accounting pronouncement. See Footnote 12 for additional information.

[2] MGE Energy short-term borrowings include MGE Energy and MGE lines of credit and MGE commercial paper.