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Concentrations - Narrative (Detail) - employee | 12 Months Ended
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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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