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Industry Segment and Geographic Data, Customer Concentration (Details) - Customer Concentration Risk [Member] - Customer | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Customer Concentration [Abstract] |  |  |
Number of largest individual customers | 5 |  |
Net Sales [Member] |  |  |
Customer Concentration [Abstract] |  |  |
Concentration risk, percentage | 69.00% | 70.00% | 70.00%
Net Sales [Member] | Five Largest Individual Customers [Member] |  |  |
Customer Concentration [Abstract] |  |  |
Concentration risk, percentage | 69.00% | 70.00% | 70.00%
Net Sales [Member] | O' Reilly [Member] |  |  |
Customer Concentration [Abstract] |  |  |
Concentration risk, percentage | 22.00% |  |
Net Sales [Member] | Advance [Member] |  |  |
Customer Concentration [Abstract] |  |  |
Concentration risk, percentage | 16.00% |  |
Net Sales [Member] | NAPA [Member] |  |  |
Customer Concentration [Abstract] |  |  |
Concentration risk, percentage | 15.00% |  |
Net Sales [Member] | AutoZone [Member] |  |  |
Customer Concentration [Abstract] |  |  |
Concentration risk, percentage | 11.00% |  |

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