Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		$ 26,159	$ 19,967
Acquired finite-lived intangible assets, weighted average useful life		14 years
Goodwill		$ 46,213	44,708
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months		1,800
Amortization of intangible assets		1,500	1,300	$ 1,200
Finite-Lived Intangible Assets, Amortization Expense, Year Four		1,500
Amortization of intangible assets, 2022		1,400
Regulated Energy
Goodwill [Line Items]
Goodwill		7,689	7,689
Unregulated Energy
Goodwill [Line Items]
Goodwill		38,524	37,019
Customer list
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	[1]	$ 16,965	16,814
Customer list | Minimum [Member]
Goodwill [Line Items]
Amortized period of acquired intangible assets		5 years
Noncompete Agreements [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		$ 3,105	$ 2,431

[1] 1) The customer relationship amounts include $6.1 million as a result of the purchase of Diversified Energy in December 2021.