Employee Benefit Plans - Schedule of Estimated Future Benefit Payments (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Chesapeake Pension Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	$ 115	[1]
2018	368	[1]
2019	106	[1]
2020	927	[1]
2021	111	[1]
Years 2022 through 2026	2,300	[1]
FPU Pension Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	3,281	[1]
2018	3,348	[1]
2019	3,424	[1]
2020	3,498	[1]
2021	3,549	[1]
Years 2022 through 2026	18,429	[1]
Chesapeake SERP
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	151	[2]
2018	150	[2]
2019	148	[2]
2020	146	[2]
2021	144	[2]
Years 2022 through 2026	748	[2]
Chesapeake Postretirement Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	90	[2]
2018	87	[2]
2019	85	[2]
2020	67	[2]
2021	64	[2]
Years 2022 through 2026	264	[2]
FPU Medical Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	86	[2]
2018	90	[2]
2019	91	[2]
2020	79	[2]
2021	80	[2]
Years 2022 through 2026	$ 389	[2]

[1] The pension plan is funded; therefore, benefit payments are expected to be paid out of the plan assets.

[2] Benefit payments are expected to be paid out of our general funds.