Employee Benefit Plans - Schedule of Amounts Not Yet Reflected in Net Periodic Benefit Cost and Included in Accumulated Other Comprehensive Income Loss or Regulatory Assets (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Interest cost		$ 50	$ 48	$ 63
Prior service cost (credit)		(216)
Net loss		15,031
Total		14,815
Accumulated other comprehensive loss pre-tax		3,363
Post-merger regulatory asset		(11,452)
Total unrecognized cost		(14,815)
Chesapeake Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost		0	141	176
Defined Benefit Plan, Expected Return (Loss) on Plan Assets		0	166	157
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		0	(257)	(243)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement		0	(1,810)	(203)
Net Periodic Cost Benefit		0	2,042	465
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		0	2,042	465
Amortization Of Pre Merger Regulatory Asset		$ 0	$ 0	$ 0
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		0.00%	2.25%	3.00%
Expected return on plan assets		0.00%	3.50%	3.50%
FPU Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost		$ 1,781	$ 1,714	$ 2,085
Prior service cost (credit)		0
Net loss		14,540
Total		14,540
Accumulated other comprehensive loss pre-tax	[1]	2,763
Post-merger regulatory asset		(11,777)
Total unrecognized cost		(14,540)
Defined Benefit Plan, Expected Return (Loss) on Plan Assets		3,430	3,306	2,967
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		(466)	(612)	(552)
Net Periodic Cost Benefit		(1,183)	(980)	(330)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		(1,183)	(980)	(330)
Amortization Of Pre Merger Regulatory Asset		$ 0	$ 0	$ 0
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		2.75%	2.50%	3.25%
Expected return on plan assets		6.00%	6.00%	6.00%
Chesapeake SERP
Defined Benefit Plan Disclosure [Line Items]
Interest cost		$ 50	$ 48
Prior service cost (credit)		0
Net loss		295
Total		295
Accumulated other comprehensive loss pre-tax	[1]	295
Post-merger regulatory asset		0
Total unrecognized cost		(295)
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		(28)	(28)	$ (20)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement		0	0	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		$ 78	$ 76	$ 83
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		2.50%	2.25%	3.00%
Chesapeake Postretirement Plan
Defined Benefit Plan Disclosure [Line Items]
Prior service cost (credit)		$ (216)
Net loss		597
Total		381
Accumulated other comprehensive loss pre-tax	[1]	381
Post-merger regulatory asset		0
Total unrecognized cost		(381)
FPU Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Prior service cost (credit)		0
Net loss		(401)
Total		(401)
Accumulated other comprehensive loss pre-tax	[1]	(76)
Post-merger regulatory asset		(325)
Total unrecognized cost		$ (401)

[1] The total amount of accumulated other comprehensive loss recorded on our consolidated balance sheet as of December 31, 2022 is net of income tax benefits of $0.9 million.