Investments in Affiliated Companies - Summarized Balance Sheet (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Equity Method Investments and Joint Ventures [Abstract] | ||
| Current assets | $ 213,815 | $ 207,997 |
| Noncurrent assets | 235,440 | 212,144 |
| Current liabilities | 37,018 | 44,741 |
| Noncurrent liabilities | $ 1,417 | $ 1,384 |
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- Definition The amount of current assets reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of current liabilities reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of noncurrent assets reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of noncurrent liabilities reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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