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Business, Product and Geographical Area Information and Concentration of Risk - Additional Information (Details) | 12 Months Ended
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Dec. 31, 2020 Productionfacility customer | Dec. 31, 2019 customer | Dec. 31, 2018 customer
Workforce Subject to Collective Bargaining Arrangements |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 63.00% |  |
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 24.00% |  |
Net sales | Customer Concentration Risk | Largest Customer |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 26.00% | 25.00% | 25.00%
Number of customers | customer | 1 | 1 | 1
Net sales | Customer Concentration Risk | Second Largest Customer |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 11.00% | 17.00% | 15.00%
Trade receivables | Customer Concentration Risk | Largest Customer |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 20.00% | 41.00% |
Trade receivables | Customer Concentration Risk | Second Largest Customer |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 13.00% | 10.00% |
Domestic |  |  |
Segment Reporting Information [Line Items] |  |  |
Number of production facilities | 12 |  |
Canada |  |  |
Segment Reporting Information [Line Items] |  |  |
Number of production facilities | 1 |  |

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