Summary of Significant Accounting Policies - Inventory Valuation (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Inventory
Raw materials	$ 200	$ 217
Work-in-process	118	148
Finished goods	789	589
Total inventory	$ 1,107	$ 954

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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