Balance Sheet Components (Narrative) (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Inventory [Line Items]
Weighted average days to maturity	136 days
Work-in-process inventories	$ 0
Excess And Obsolete Inventory [Member]
Inventory [Line Items]
Loss contingency receivable	$ 573,000	$ 2,377,000

Period between issuance and maturity of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

+ References

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- Definition

Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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