Balance Sheet Account Detail - Summary of Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Key employee life insurance – cash surrender value (associated with our deferred compensation plan - see Note 7	$ 3,547	$ 6,274
Research & development supplies and other	119	246
Income tax receivable - non-current portion	334	668
Other assets	$ 4,000	$ 7,188

Cash Surrender Value of Life Insurance, Noncurrent

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- Definition

Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- References

No definition available.

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- Definition

Amount of noncurrent assets classified as other.

+ References

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- Definition

Amount of consideration paid in advance for supplies that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
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