Rates and Other Regulatory Activities - Additional Information (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2022 USD ($) Dekatherm mi	Dec. 31, 2021 USD ($)
Rates and Other Regulatory Activities [Line Items]
COVID-19 Regulatory Asset	$ 1,800	$ 2,300
Interim Rates	7,700
Permanent Rates	24,100
Requested Interim Rates	7,200
Florida Public Utilities Company [Member]
Rates and Other Regulatory Activities [Line Items]
COVID-19 Settlement Amount	2,100
Delaware natural gas division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	12,510	12,591
Maryland Division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	3,772	3,840
Sandpiper [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	3,626	3,656
Central Florida Gas Division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	7,939	8,032
Florida Public Utilities Company [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	19,058	19,189
Fort Meade and Indiantown Divisions [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	265	271
FPU electric division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	5,115	5,237
Eastern Shore Gas Company [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	34,190	34,190
Elkton Gas [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	$ 1,074	$ 1,091
Beachside Expansion | Peninsula Pipeline Company [Member]
Rates and Other Regulatory Activities [Line Items]
Number of Mainline Pipeline Miles | mi	11.3
Additional Firm Natural Gas Transportation Deliverability | Dekatherm	10,176
Winter Haven Expansion | Peninsula Pipeline Company [Member]
Rates and Other Regulatory Activities [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm	6,800
Twin Lakes Expansion | Peninsula Pipeline Company [Member]
Rates and Other Regulatory Activities [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm	2,400