Employee Benefit Plans - Amounts Included in Regulatory Asset and Accumulated Other Comprehensive Income/Loss Recognized as Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Florida Public Utilities Company Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	$ 110	$ 124
Recognized from accumulated other comprehensive loss	21	24
Recognized from regulatory asset	89	100
Total recognized in net periodic benefit cost	110
Chesapeake Pension SERP [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Total recognized in net periodic benefit cost	$ 124	$ 124