Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 104,733	$ 95,959
Accounts receivable, less reserves	38,129	39,887
Other accounts receivables, less reserves	7,588	8,530
Unbilled revenues	21,764	29,846
Materials and supplies, at average cost	21,835	18,561
Fossil fuel, at average cost	10,017	9,757
Stored natural gas, at average cost	14,758	12,819
Prepaid taxes	12,406	26,636
Regulatory assets - current	7,377	6,414
Assets held for sale	6,707	14,813
Other current assets	10,043	12,293
Total Current Assets	255,357	275,515
Regulatory assets	146,006	158,485
Pension and other postretirement benefit asset	3,471	2,020
Other deferred assets and other	6,311	6,691
Property, Plant, and Equipment:
Property, plant, and equipment, net	1,270,124	1,245,269
Construction work in progress	42,276	36,790
Total Property, Plant, and Equipment	1,312,400	1,282,059
Investments	86,455	76,290
Total Assets	1,810,000	1,801,060
Current Liabilities:
Long-term debt due within one year	4,428	4,333
Short-term debt	7,000	0
Accounts payable	31,519	47,799
Accrued interest and taxes	4,750	5,495
Accrued payroll related items	9,981	11,892
Regulatory liabilities - current	6,353	6,910
Derivative liabilities	8,288	7,620
Other current liabilities	12,263	19,456
Total Current Liabilities	84,582	103,505
Other Credits:
Deferred income taxes	389,179	383,813
Investment tax credit - deferred	885	947
Regulatory liabilities	28,253	22,173
Accrued pension and other postretirement benefits	65,616	74,347
Derivative liabilities	34,890	42,970
Other deferred liabilities and other	63,942	66,426
Total Other Credits	582,765	590,676
Capitalization:
Common shareholders equity	753,247	724,088
Long-term debt	389,406	382,791
Total Capitalization	1,142,653	1,106,879
Commitments and contingencies (see Footnote 7)
Total Liabilities and Capitalization	1,810,000	1,801,060
MGE [Member]
Current Assets:
Cash and cash equivalents	1,954	10,768
Accounts receivable, less reserves	38,129	39,887
Affiliate receivables	683	539
Other accounts receivables, less reserves	7,529	6,363
Unbilled revenues	21,764	29,846
Materials and supplies, at average cost	21,835	18,561
Fossil fuel, at average cost	10,017	9,757
Stored natural gas, at average cost	14,758	12,819
Prepaid taxes	12,524	25,798
Regulatory assets - current	7,377	6,414
Assets held for sale	6,707	14,813
Other current assets	10,010	12,268
Total Current Assets	153,287	187,833
Affiliate receivable long-term	3,839	4,236
Regulatory assets	146,006	158,485
Pension and other postretirement benefit asset	3,471	2,020
Other deferred assets and other	4,066	4,353
Property, Plant, and Equipment:
Property, plant, and equipment, net	1,270,153	1,244,648
Construction work in progress	42,276	36,790
Total Property, Plant, and Equipment	1,312,429	1,281,438
Investments	423	487
Total Assets	1,623,521	1,638,852
Current Liabilities:
Long-term debt due within one year	4,428	4,333
Short-term debt	7,000	0
Accounts payable	31,508	47,790
Accrued interest and taxes	5,717	5,440
Accrued payroll related items	9,981	11,892
Regulatory liabilities - current	6,353	6,910
Derivative liabilities	8,288	7,620
Other current liabilities	12,079	19,347
Total Current Liabilities	85,354	103,332
Other Credits:
Deferred income taxes	346,278	343,117
Investment tax credit - deferred	885	947
Regulatory liabilities	28,253	22,173
Accrued pension and other postretirement benefits	65,616	74,347
Derivative liabilities	34,890	42,970
Other deferred liabilities and other	63,942	66,426
Total Other Credits	539,864	549,980
Capitalization:
Common shareholders equity	493,508	487,084
Noncontrolling interest	115,389	115,665
Total Equity	608,897	602,749
Long-term debt	389,406	382,791
Total Capitalization	998,303	985,540
Commitments and contingencies (see Footnote 7)
Total Liabilities and Capitalization	$ 1,623,521	$ 1,638,852