Rates and Other Regulatory Activities - Additional Information (Detail) $ in Thousands		12 Months Ended
		Dec. 31, 2022 USD ($) Dekatherm mi	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Rates and Other Regulatory Activities [Line Items]
Restricted Payment		$ 326,400
Regulatory Assets		149,654	$ 123,967
Revenues		680,704	569,968	$ 488,198
Interim Rates		7,700
Permanent Rates		24,100
Annual Rate Case Recovery		17,200
COVID-19 Regulatory Asset		1,200	2,300
Underrecovered purchased fuel costs
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[1]	43,583	$ 9,199
Florida Public Utilities Company [Member]
Rates and Other Regulatory Activities [Line Items]
COVID-19 Settlement Amount		$ 2,100
Winter Haven Expansion | Peninsula Pipeline Company
Rates and Other Regulatory Activities [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm		6,800
Beachside Expansion | Peninsula Pipeline Company
Rates and Other Regulatory Activities [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm		10,176
Number of Mainline Pipeline Miles | mi		11.3
Twin Lakes Expansion | Peninsula Pipeline Company
Rates and Other Regulatory Activities [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm		2,400
Elkton Gas [Member] | Regulated Energy [Member]
Rates and Other Regulatory Activities [Line Items]
Number of customers acquired through acquisition		7,000

[1] We are allowed to recover the asset or are required to pay the liability in rates. We do not earn an overall rate of return on these assets.(2) At December 31, 2022, includes $21.2 million being recovered over a three year period primarily concentrated in our electric division. Per Florida PSC approval, our electric division was allowed to recover these amounts over an extended period of time in an effort to reduce the impact of increased commodity prices to our customers. Recovery of these costs began in January 2023.