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Business, Product and Geographical Area Information and Concentration of Risk - Schedules of Concentration of Risk, by Risk Factor (Details) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Geographic Concentration Risk [Member] | Net sales |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 14.00% | 15.00% | 18.00%
Largest Customer [Member] | Customer Concentration Risk [Member] | Trade receivables |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 41.00% | 31.00% |
Largest Customer [Member] | Customer Concentration Risk [Member] | Net sales |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 25.00% | 25.00% | 27.00%
Second Largest Customer [Member] | Customer Concentration Risk [Member] | Trade receivables |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 10.00% | 11.00% |
Second Largest Customer [Member] | Customer Concentration Risk [Member] | Net sales |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 17.00% | 15.00% | 12.00%
Top five major suppliers [Member] | Supplier concentration risk | Aluminum |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 74.00% | 81.00% | 85.00%
Largest supplier [Member] | Supplier concentration risk | Aluminum |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 22.00% | 22.00% | 36.00%
Second and third largest suppliers [Member] | Supplier concentration risk | Aluminum |  |  |
Concentration Risk |  |  |
Concentration risk, percentage | 32.00% | 38.00% | 33.00%

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