Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020 USD ($) Customer	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) Customer Segment	Jun. 30, 2019 USD ($)	Dec. 31, 2019 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.
Contract asset	$ 0		$ 0		$ 0
Product revenue recognized, that were included in deferred product revenue			$ 500,000
Application of an optional exemption not to disclose the value of unsatisfied performance obligations			true
Number of major customers representing outstanding trade receivables | Customer	2		2		3
Protracted length of inventory			1 year
Inventory valuation reserves	$ 100,000		$ 100,000		$ 100,000
Non-cash purchases of capital expenditures			300,000	$ 2,900,000
Accumulated amortization intangible assets	2,000,000.0		$ 2,000,000.0		1,900,000
Estimated useful life of intangible assets			10 years
Number of reportable segments | Segment			1
Impairment charges acquired intangible assets	0	$ 0	$ 0	$ 0
Period of warranty			1 year
Warranty claim liability	$ 0		$ 0		$ 0
Trade Accounts Receivable | Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			47.00%		56.00%
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
Shelf lives of inventory			24 months
Estimated useful life of property and equipment			5 years