Business Description and Summary of Significant Accounting Policies - Additional Information (Details)	6 Months Ended		18 Months Ended
	Jun. 30, 2022 USD ($) Y	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for doubtful accounts	$ 131,000		$ 131,000	$ 131,000
Warranty period	27 months
Warranty reserve	$ 496,000		496,000	511,000
Inventory reserve	1,663,000		1,663,000	$ 1,742,000
Income taxes, refund received	811,000	$ 0
Income taxes paid	50,000	180,000
Interest paid	$ 66,000	$ 73,000
Impairment of long-lived assets			$ 0
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Period inventory is expected to be used	1 year
Number of years of customer requirements | Y	2
Number of year's supply | Y	1