Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities:
Net Income	$ 33,814	$ 31,078
Items not affecting cash:
Depreciation and amortization	26,600	24,611
Deferred income taxes	(521)	6,056
Provision for doubtful receivables	2,200	441
Employee benefit plan cost (credit)	77	(648)
Equity earnings in investments	(2,746)	(2,611)
Other items	939	(1,366)
Changes in working capital items:
Decrease in current assets	18,417	28,211
Decrease in accounts payable	(13,072)	(18,509)
Increase (decrease) in current liabilities	(106)	(6,742)
Dividends from investments	2,106	2,206
Cash contributions to pension and other postretirement plans	(1,825)	(1,785)
Other noncurrent items, net	(68)	(4,939)
Cash Provided by Operating Activities	65,815	56,003
Investing Activities:
Capital expenditures	(44,771)	(47,556)
Capital contributions to investments	(1,381)	(1,527)
Other	(274)	(483)
Cash Used for Investing Activities	(46,426)	(49,566)
Financing Activities:
Cash dividends paid on common stock	(15,460)	(14,736)
Repayments of long-term debt	(1,274)	(20,542)
Issuance of long-term debt	0	69,300
Proceeds from (repayments of) short-term debt	3,000	(37,500)
Other	(554)	(1,296)
Cash Used for Financing Activities	(14,288)	(4,774)
Change in cash, cash equivalents, and restricted cash	5,101	1,663
Cash, cash equivalents, and restricted cash at beginning of period	15,026	17,968
Cash, cash equivalents, and restricted cash at end of period	20,127	19,631
Significant noncash investing activities:
Accrued capital expenditures	6,514	4,402
MGE [Member]
Operating Activities:
Net Income	32,200	29,643
Items not affecting cash:
Depreciation and amortization	26,600	24,611
Deferred income taxes	(784)	5,679
Provision for doubtful receivables	2,200	441
Employee benefit plan cost (credit)	77	(648)
Other items	1,203	(1,146)
Changes in working capital items:
Decrease in current assets	17,746	27,758
Decrease in accounts payable	(13,069)	(18,515)
Increase (decrease) in current liabilities	1,778	(4,835)
Cash contributions to pension and other postretirement plans	(1,825)	(1,785)
Other noncurrent items, net	(1,092)	(5,224)
Cash Provided by Operating Activities	65,034	55,979
Investing Activities:
Capital expenditures	(44,771)	(47,556)
Other	(421)	(387)
Cash Used for Investing Activities	(45,192)	(47,943)
Financing Activities:
Cash dividends paid to parent by MGE	(14,000)	(12,500)
Distributions to parent from noncontrolling interest	(4,000)	(6,000)
Repayments of long-term debt	(1,274)	(20,542)
Issuance of long-term debt	0	69,300
Proceeds from (repayments of) short-term debt	3,000	(37,500)
Other	(554)	(1,296)
Cash Used for Financing Activities	(16,828)	(8,538)
Change in cash, cash equivalents, and restricted cash	3,014	(502)
Cash, cash equivalents, and restricted cash at beginning of period	6,705	10,500
Cash, cash equivalents, and restricted cash at end of period	9,719	9,998
Significant noncash investing activities:
Accrued capital expenditures	$ 6,514	$ 4,402