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Concentrations - Narrative (Detail) - employee	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Concentration Risk [Line Items]
Entity number of employees	228
Collective Bargaining Agreements
Concentration Risk [Line Items]
Entity number of employees	28
Accounts Receivable | Customer Concentration Risk | Two Customers
Concentration Risk [Line Items]
Concentration Risk, Percentage		81.00%
Accounts Receivable | Customer Concentration Risk | One Customer
Concentration Risk [Line Items]
Concentration Risk, Percentage	78.00%
Revenue | Customer Concentration Risk | Four Customers
Concentration Risk [Line Items]
Concentration Risk, Percentage		73.00%	66.00%
Revenue | Customer Concentration Risk | Three Customers
Concentration Risk [Line Items]
Concentration Risk, Percentage	64.00%
Accounts Payables | Supplier Concentration Risk | One Vendor
Concentration Risk [Line Items]
Concentration Risk, Percentage		26.00%
Accounts Payables | Supplier Concentration Risk | Three Vendors
Concentration Risk [Line Items]
Concentration Risk, Percentage	42.00%
Cost of Goods Sold | Supplier Concentration Risk | One Supplier
Concentration Risk [Line Items]
Concentration Risk, Percentage	45.00%	44.00%	40.00%

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Number of persons employed by the Entity

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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