For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 280
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- Definition

Description of risks that arise due to the volume of business transacted with a particular supplier or reliance placed on that supplier. At a minimum, the description informs financial statement users of the general nature of the risk.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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Segment Information Narrative (Details)	3 Months Ended		9 Months Ended
Segment Information Narrative (Details)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue, Major Customer [Line Items]
Number of reportable segments			3
Concentration risk, supplier			We currently buy a majority of our integrated circuit board assemblies from three suppliers. Management believes that other suppliers could provide similar products, but a change in suppliers, disputes with our suppliers, or unexpected constraints on the suppliers' production capacity could adversely affect operating results.
Sales [Member] \| Customer A [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	0.00%	10.00%	11.00%	11.00%