Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 3,590	$ 4,064
Finished goods	5,636	5,749
Reserves for excess, obsolete, and slow-moving inventories	(3,326)	(3,645)	$ (4,212)
Inventories, net	$ 5,900	$ 6,168

Inventory Valuation Reserves, Raw Materials

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- References

No definition available.

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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 2
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- Definition

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

+ References

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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 330
-SubTopic 10
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