Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended	12 Months Ended
Mar. 31, 2021 USD ($) Customer Segment	Dec. 31, 2020 USD ($) Customer
Summary Of Significant Accounting Policies [Line Items]
Description of payment of customer invoice contract	The Company invoices its customers based upon the terms in the contracts, which generally requires payment 30 to 60 days from the date of invoice.
Product revenue recognized, that were included in deferred product revenue	$ 300,000
Application of an optional exemption not to disclose the value of unsatisfied performance obligations	true
Number of major customers representing outstanding accounts receivable \| Customer	3	3
Number of reportable segments \| Segment	1
Period of warranty	1 year
Warranty claim liability	$ 0	$ 0
Trade Accounts Receivable \| Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	64.00%	51.00%
Other Assets
Summary Of Significant Accounting Policies [Line Items]
Cash surrender value of associated life insurance policies	$ 800,000	$ 200,000
Other Long-term Liabilities
Summary Of Significant Accounting Policies [Line Items]
Liability for deferred compensation	$ 800,000	200,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Payment of customer invoice contract period	30 days
Shelf lives of inventory	18 months
Estimated useful life of property and equipment	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Payment of customer invoice contract period	60 days
Percentage of deferred compensation from base salary	80.00%
Percentage of deferred compensation from variable compensation	100.00%
Shelf lives of inventory	24 months
Inventory valuation reserves	$ 100,000	100,000
Estimated useful life of property and equipment	5 years
Product
Summary Of Significant Accounting Policies [Line Items]
Contract asset	$ 0	$ 0

Cumulative outstanding account receivable number of major customers.

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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