Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Nonrelated party	Common Stock	Other Paid-in Capital	Other Paid-in Capital Nonrelated party	Retained Earnings	Retained Earnings Nonrelated party	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2021			1,000
Beginning balance at Dec. 31, 2021	$ 362,937		$ 1	$ 136,033		$ 227,023		$ (120)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	124,781					124,781
Other comprehensive income	85							85
Net transfers (to) from CEHI, LLC and/or MDU Resources Group, Inc.	(105,556)			294		(105,850)
Ending balance (in shares) at Dec. 31, 2022			1,000
Ending balance at Dec. 31, 2022	382,247		$ 1	136,327		245,954		(35)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	137,230					137,230
Other comprehensive income	35							35
Net transfers (to) from CEHI, LLC and/or MDU Resources Group, Inc.	$ (70,662)			(143)		(70,519)
Ending balance (in shares) at Dec. 31, 2023	1,000		1,000
Ending balance at Dec. 31, 2023	$ 448,850		$ 1	136,184		312,665		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	143,421					143,421
Other comprehensive income	0
Stock-based compensation (in shares)			8,865
Stock-based compensation	1,472			2,047		(575)
Retirement of historical common stock in connection with the Separation (in shares)			(1,000)
Retirement of historical common stock in connection with the Separation	0		$ (1)	1
Issuance of common stock in connection with the Separation (in shares)			50,972,059
Issuance of common stock in connection with the Separation	$ 0		$ 510	(510)
Net transfers (to) from CEHI, LLC and/or MDU Resources Group, Inc.		$ (171,131)			$ 408		$ (171,539)
Ending balance (in shares) at Dec. 31, 2024	50,980,924		50,980,924
Ending balance at Dec. 31, 2024	$ 422,612		$ 510	$ 138,130		$ 283,972		$ 0