Balance Sheet Account Detail - Summary of Other Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Key employee life insurance – cash surrender value (associated with deferred compensation plan - see Note 6)	$ 3,073	$ 3,547
Income tax receivable - non-current portion	0	334
Research & development supplies and other	114	119
Other assets	$ 3,187	$ 4,000

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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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.

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Amount of noncurrent assets classified as other.

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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.

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