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Segment Reporting (Schedule of Automotive Customers Individually Accounted For 10% or More of Net Sales) (Details) - automotive_customer | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Revenue, Major Customer [Line Items] |  |  |
Percentage net sales invoiced and paid in foreign currencies | 8.00% | 8.00% | 7.00%
Number of customers which individually accounted for 10% or more of net sales | 3 |  |
Customer concentration risk | Toyota Motor Company |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenue individually accounted by customers (less than 10% for Ford Motor Company in 2018 and for Daimler AG in 2016) | 13.00% | 12.00% | 11.00%
Customer concentration risk | Volkswagen Group |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenue individually accounted by customers (less than 10% for Ford Motor Company in 2018 and for Daimler AG in 2016) | 15.00% | 15.00% | 14.00%
Customer concentration risk | Ford Motor Company |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenue individually accounted by customers (less than 10% for Ford Motor Company in 2018 and for Daimler AG in 2016) | 10.00% | 10.00% | 11.00%
Customer concentration risk | Daimler Group |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenue individually accounted by customers (less than 10% for Ford Motor Company in 2018 and for Daimler AG in 2016) | 10.00% | 10.00% | 10.00%

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