Employee Retirement Plans (Details) - USD ($) $ in Thousands |
3 Months Ended | |
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Mar. 31, 2018 |
Mar. 31, 2017 |
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| Pension plan | ||
| Components of net periodic cost: | ||
| Service cost | $ 102 | $ 89 |
| Interest cost | 389 | 403 |
| Expected return on plan assets | (475) | (448) |
| Amortization of net (gain) loss | 176 | 181 |
| Net periodic pension cost | 192 | 225 |
| Employer contributions during the period | 14 | 529 |
| Pension plan | Minimum | ||
| Components of net periodic cost: | ||
| Estimated total required contributions | 72 | |
| Other postretirement benefit cost | ||
| Components of net periodic cost: | ||
| Service cost | 47 | 51 |
| Interest cost | 58 | 70 |
| Amortization of net (gain) loss | (52) | (27) |
| Net periodic pension cost | $ 53 | $ 94 |
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- Definition The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the current fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions. No definition available.
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- Definition The amount of gains or losses recognized in net periodic benefit cost. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of contributions made by the employer to defined benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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