Business Description and Summary of Significant Accounting Policies - Additional Information (Details)		12 Months Ended
	Dec. 09, 2019 USD ($)	Dec. 31, 2019 USD ($) Y	Dec. 31, 2018 USD ($)	Oct. 21, 2019 USD ($)	Sep. 30, 2019 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for doubtful accounts		$ 337,000	$ 170,000
Warranty period		27 months
Inventory reserve		$ 1,437,000	1,543,000
Interest paid		125,000	107,000
Capitalised tooling				$ 143,000
Additional converted cost				$ 18,000
Warranty reserve		420,000	428,000
Income taxes paid		524,000	1,325,000
Impairment of long-lived assets		$ 0	$ 0
Concentration risk, benchmark description		No other customers of the ATG or CPG represented more than 10% of the Company's consolidated revenues in either of these years
Other non-current assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Note receivable					$ 125,000
Selling, general & administrative expenses
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Costs of dissolution of capitalized assets	$ 237,000
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Period inventory is expected to be used		2 years
Number of year's supply | Y		1
Number of years of customer requirements | Y		2
Customer Concentration Risk | Advanced Technology Products | Sales Revenue | Two Customers
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration Risk, Percentage		55.00%	49.00%
Concentration risk, benchmark description		more than 10%