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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Commitments and Contingencies - Concentration of Credit Risk (Details) - customer	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Ten largest customers
Concentration of Credit Risk
Number of customers	10
Accounts Receivable \| Credit Concentration Risk \| Ten largest customers
Concentration of Credit Risk
Concentration Risk (as a percent)	62.00%	67.00%
Accounts Receivable \| Credit Concentration Risk \| Customer A
Concentration of Credit Risk
Concentration Risk (as a percent)		16.00%
Accounts Receivable \| Credit Concentration Risk \| Customer B
Concentration of Credit Risk
Concentration Risk (as a percent)		21.00%
Net Sales \| Customer Concentration Risk \| Customer A
Concentration of Credit Risk
Concentration Risk (as a percent)	13.00%	11.00%
Net Sales \| Customer Concentration Risk \| Customer C
Concentration of Credit Risk
Concentration Risk (as a percent)			12.00%