Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Operating Activities:
Net Income	$ 41,592	$ 33,814
Items not affecting cash:
Depreciation and amortization	27,678	26,600
Deferred income taxes	1,344	(521)
Provision for doubtful receivables	2,200	2,200
Employee benefit plan cost (credit)	(1,181)	77
Equity earnings in investments	(3,181)	(2,746)
Other items	832	939
Changes in working capital items:
Current assets	15,343	18,417
Accounts payable	(16,485)	(13,072)
Other current liabilities	5,472	(106)
Dividends from investments	3,287	2,106
Cash contributions to pension and other postretirement plans	(1,914)	(1,825)
Other noncurrent items, net	2,875	(68)
Cash Provided by Operating Activities	77,862	65,815
Investing Activities:
Capital expenditures	(47,653)	(44,771)
Capital contributions to investments	(2,540)	(1,381)
Other	(399)	(274)
Cash Used for Investing Activities	(50,592)	(46,426)
Financing Activities:
Issuance of common stock, net	3,279	0
Cash dividends paid on common stock	(16,428)	(15,460)
Repayments of long-term debt	(1,308)	(1,274)
Proceeds from short-term debt	0	3,000
Other	(650)	(554)
Cash Used for Financing Activities	(15,107)	(14,288)
Change in cash, cash equivalents, and restricted cash	12,163	5,101
Cash, cash equivalents, and restricted cash at beginning of period	24,496	15,026
Cash, cash equivalents, and restricted cash at end of period	36,659	20,127
Significant noncash investing activities:
Accrued capital expenditures	9,802	6,514
MGE [Member]
Operating Activities:
Net Income	39,803	32,200
Items not affecting cash:
Depreciation and amortization	27,678	26,600
Deferred income taxes	982	(784)
Provision for doubtful receivables	2,200	2,200
Employee benefit plan cost (credit)	(1,181)	77
Other items	1,158	1,203
Changes in working capital items:
Current assets	15,369	17,746
Accounts payable	(16,498)	(13,069)
Other current liabilities	4,882	1,778
Cash contributions to pension and other postretirement plans	(1,914)	(1,825)
Other noncurrent items, net	1,475	(1,092)
Cash Provided by Operating Activities	73,954	65,034
Investing Activities:
Capital expenditures	(47,653)	(44,771)
Other	(396)	(421)
Cash Used for Investing Activities	(48,049)	(45,192)
Financing Activities:
Cash dividends paid to parent by MGE	(13,500)	(14,000)
Distributions to parent from noncontrolling interest	(4,000)	(4,000)
Repayments of long-term debt	(1,308)	(1,274)
Proceeds from short-term debt	0	3,000
Other	(650)	(554)
Cash Used for Financing Activities	(19,458)	(16,828)
Change in cash, cash equivalents, and restricted cash	6,447	3,014
Cash, cash equivalents, and restricted cash at beginning of period	20,059	6,705
Cash, cash equivalents, and restricted cash at end of period	26,506	9,719
Significant noncash investing activities:
Accrued capital expenditures	$ 9,802	$ 6,514