Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Operating Activities:
Net Income	$ 68,090	$ 57,608
Items not affecting cash:
Depreciation and amortization	56,032	53,532
Deferred income taxes	2,578	(1,351)
Provision for doubtful receivables	4,400	4,400
Employee benefit plan (credit) cost	(2,320)	323
Equity earnings in investments	(6,241)	(5,526)
Other items	378	930
Changes in working capital items:
Current assets	13,446	22,086
Accounts payable	(13,491)	(9,646)
Other current liabilities	1,298	3,718
Dividends from investments	6,008	4,238
Cash contributions to pension and other postretirement plans	(3,800)	(3,634)
Other noncurrent items, net	7,575	3,756
Cash Provided by Operating Activities	133,953	130,434
Investing Activities:
Capital expenditures	(111,753)	(111,622)
Capital contributions to investments	(5,871)	(3,159)
Other	(630)	1,272
Cash Used for Investing Activities	(118,254)	(113,509)
Financing Activities:
Issuance of common stock, net	3,750	0
Cash dividends paid on common stock	(32,872)	(30,930)
Repayments of long-term debt	(2,625)	(2,556)
Proceeds from short-term debt	5,500	21,800
Other	(812)	(728)
Cash Used for Financing Activities	(27,059)	(12,414)
Change in cash, cash equivalents, and restricted cash	(11,360)	4,511
Cash, cash equivalents, and restricted cash at beginning of period	24,496	15,026
Cash, cash equivalents, and restricted cash at end of period	13,136	19,537
Significant noncash investing activities:
Accrued capital expenditures	9,120	11,416
MGE [Member]
Operating Activities:
Net Income	64,278	53,954
Items not affecting cash:
Depreciation and amortization	56,032	53,532
Deferred income taxes	1,785	(1,287)
Provision for doubtful receivables	4,400	4,400
Employee benefit plan (credit) cost	(2,319)	323
Other items	766	1,446
Changes in working capital items:
Current assets	13,448	22,098
Accounts payable	(13,533)	(9,642)
Other current liabilities	836	4,774
Cash contributions to pension and other postretirement plans	(3,800)	(3,634)
Other noncurrent items, net	6,095	2,465
Cash Provided by Operating Activities	127,988	128,429
Investing Activities:
Capital expenditures	(111,753)	(111,622)
Other	(765)	(894)
Cash Used for Investing Activities	(112,518)	(112,516)
Financing Activities:
Cash dividends paid to parent by MGE	(23,500)	(24,000)
Distributions to parent from noncontrolling interest	(8,000)	(10,000)
Repayments of long-term debt	(2,625)	(2,556)
Proceeds from short-term debt	5,500	21,800
Other	(812)	(728)
Cash Used for Financing Activities	(29,437)	(15,484)
Change in cash, cash equivalents, and restricted cash	(13,967)	429
Cash, cash equivalents, and restricted cash at beginning of period	20,059	6,705
Cash, cash equivalents, and restricted cash at end of period	6,092	7,134
Significant noncash investing activities:
Accrued capital expenditures	$ 9,120	$ 11,416