Basis of Presentation and Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue from External Customer [Line Items]
Net sales	$ 2,637	$ 3,783
Commercial
Revenue from External Customer [Line Items]
Net sales	913	1,736
MMM products
Revenue from External Customer [Line Items]
Net sales	$ 1,724	$ 2,047