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				6 Months Ended
		Jun. 30, 2022		Jun. 30, 2021		Jun. 30, 2022		Jun. 30, 2021
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Prior service cost (credit)		$ (19)		$ (19)		$ (38)		$ (38)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		143		230		286		458
Recognized from accumulated other comprehensive loss		24	[1]	87	[1]	48	[2]	171	[2]
Recognized from regulatory asset		100		124		200		249
Defined Benefit Plan Actuarial Gain Loss, Net Settlement				211				420
Total recognized in net periodic benefit cost		124		211		248		420
Chesapeake Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		0		60		0		120
Recognized from accumulated other comprehensive loss		0	[1]	60	[1]	0	[2]	120	[2]
Total recognized in net periodic benefit cost		0		60		0		120
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)		124		155		248		310
Recognized from accumulated other comprehensive loss		24	[1]	29	[1]	48	[2]	58	[2]
Recognized from regulatory asset		100		126		200		252
Total recognized in net periodic benefit cost		124		155		248		310
Chesapeake Pension SERP [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		7		7		14		14
Recognized from accumulated other comprehensive loss		7	[1]	7	[1]	14	[2]	14	[2]
Defined Benefit Plan Actuarial Gain Loss, Net Settlement				7				14
Total recognized in net periodic benefit cost		7		7		14		14
Chesapeake Postretirement Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Prior service cost (credit)		(19)		(19)		(38)		(38)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		12		10		24		18
Recognized from accumulated other comprehensive loss		(7)	[1]	(9)	[1]	(14)	[2]	(20)	[2]
Total recognized in net periodic benefit cost		$ (7)		(9)		$ (14)		(20)
Florida Public Utilities Company Medical Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)				(2)				(4)
Recognized from accumulated other comprehensive loss	[2]							(1)
Recognized from regulatory asset				(2)				(3)
Total recognized in net periodic benefit cost				$ (2)				$ (4)

[1] .

[2] 1) See Note 9, Stockholders' Equity.