Employee Benefit Plans - Schedule of Estimated Future Benefit Payments (Detail) $ in Thousands	Dec. 31, 2016 USD ($)
Chesapeake Pension Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	$ 746	[1]
2018	664	[1]
2019	713	[1]
2020	649	[1]
2021	902	[1]
Years 2022 through 2026	5,020	[1]
FPU Pension Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	3,041	[1]
2018	3,128	[1]
2019	3,235	[1]
2020	3,319	[1]
2021	3,370	[1]
Years 2022 through 2026	18,447	[1]
Chesapeake SERP
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	151	[2]
2018	150	[2]
2019	149	[2]
2020	148	[2]
2021	376	[2]
Years 2022 through 2026	732	[2]
Chesapeake Postretirement Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	83	[2]
2018	82	[2]
2019	82	[2]
2020	76	[2]
2021	72	[2]
Years 2022 through 2026	319	[2]
FPU Medical Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	129	[2]
2018	93	[2]
2019	99	[2]
2020	93	[2]
2021	95	[2]
Years 2022 through 2026	$ 405	[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.