Retirement Plans - Additional Information (Details) - USD ($) $ in Thousands |
9 Months Ended | ||
---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Dec. 31, 2017 |
|
Defined Benefit Plan Disclosure [Line Items] | |||
Contributions to defined benefit plan | $ 160 | ||
Pension plan | |||
Defined Benefit Plan Disclosure [Line Items] | |||
Service period | 5 years | ||
Assumptions used in determining periodic pension cost: | |||
Discount rate | 3.70% | 3.90% | |
Expected long-term rate of return on plan assets | 7.50% | 7.50% | |
Pension plan | Equities | |||
Current investment policy targets: | |||
Current investment mix | 65.00% | 57.00% | |
Pension plan | Treasury/Corporate Notes | |||
Current investment policy targets: | |||
Current investment mix | 34.00% | 37.00% | |
Pension plan | Money market funds | |||
Current investment policy targets: | |||
Current investment mix | 1.00% | 6.00% |