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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract] |  |  |
401(k) plan, minimum eligibility age | 18 years |  |
401(k) plan, requisite service period | 6 months |  |
401(k) plan, maximum annual contribution per employee, percent | 100.00% |  |
401(k) plan, employer's matching contribution, annual vesting percentage | 20.00% |  |
401(k) plan, employer contribution, ultimate vesting percentage | 100.00% |  |
401(k) plan, employer's matching contribution, vesting term | 6 years |  |
401(k) plan, employer contribution amount | $ 301 | $ 295 | $ 387
Operating leases, maximum term | 5 years |  |
Operating leases, rent expense | $ 310 | $ 325 | $ 375

X
- Definition Defined Contribution Plan, Eligibility Age, Minimum + References No definition available. + Details
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- Definition Defined Contribution Plan, Employer Contribution Amount + References No definition available. + Details
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- Definition Defined Contribution Plan, Employer Contribution, Ultimate Vesting Percentage + References No definition available. + Details
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- Definition Defined Contribution Plan, Employers Matching Contribution, Vesting Term + References No definition available. + Details
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- Definition Defined Contribution Plan, Requisite Service Period + References No definition available. + Details
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- Definition Operating Leases of Lessee, Maximum Term + References No definition available. + Details
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- Definition Percentage of employer's matching contributions to a defined contribution plan that vests in a given year. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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