Business Description, Basis of Presentation and Significant Accounting Policies - Deferred Revenue and Associated Costs of Goods Sold and Gross Profit (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Business Description, Basis of Presentation and Significant Accounting Policies
Deferred revenue	$ 54	$ 123
Deferred cost of goods sold
Deferred gross profit	$ 54	$ 123