Organization and Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2021 USD ($) customer country	Jun. 30, 2021 USD ($) customer item segment country	Dec. 31, 2020 USD ($) customer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of reportable segments | segment		2
Warranty period		1 year
Cash surrender value of corporate-owned life insurance policies	$ 5,055	$ 5,055	$ 4,654
Investments in number of unconsolidated affiliates | item		3
Restricted cash balance	60	$ 60	62
Prepaid Expenses and Other Current Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash balance	$ 100	$ 100	$ 100
Net Sales | Geographic Concentration Risk
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of countries outside the U.S. representing more than 10% of total net sales | country	0	0
Net Sales | Customer Concentration Risk
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of major customers | customer	0	0
Accounts and notes receivable and contract assets | Customer Concentration Risk
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of major customers | customer		0	0