Retirement Plans and Employee Rights Upon Termination (Narrative) (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Retirement Benefits [Abstract] | |||
| Severance liabilities | $ 3,900,000 | $ 3,700,000 | |
| Employee contribution percentage | 4.00% | ||
| Employer contributions matching amount | $ 3,500 | ||
| Percent of employee contribution matched by the Company | 50.00% | ||
| Employer contribution amount | $ 3,700,000 | 3,800,000 | $ 4,200,000 |
| Future benefits to employees | $ 3,000,000 | $ 2,700,000 | |
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- Definition Amount of benefits expected to be paid from a defined benefit plan. No definition available.
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- Definition Amount of severance liabilities. No definition available.
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- References No definition available.
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. No definition available.
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- Definition Percentage employer matches of the employee's percentage contribution matched. No definition available.
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. No definition available.
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