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Inventories (Tables) | 12 Months Ended
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Dec. 31, 2017
Inventory Disclosure [Abstract] |
Schedule of Inventories | Inventories at December 31 consisted of the following (in thousands):
| 2017 |  | 2016
Raw material | $ | 42,661 |  |  | $ | 41,758 |
Work-in-process | 10,598 |  |  | 12,268 |
Finished goods | 33,113 |  |  | 35,586 |
Total inventories | $ | 86,372 |  |  | $ | 89,612 |
Summary of Activity within the Reserve for Excess, Obsolete, and Slow Moving Inventory | The following table summarizes activity recorded within the reserve for excess, obsolete and slow moving inventory for the years ended December 31 (in thousands):
| 2017 |  | 2016 |  | 2015
Beginning balance | $ | 3,801 |  |  | $ | 7,428 |  |  | $ | 5,575 |
Excess, obsolete and slow moving inventory expense | 1,276 |  |  | (239 | ) |  | 1,539 |
Scrapped inventory and other adjustments | (1,382 | ) |  | (3,388 | ) |  | 314 |
Ending balance | $ | 3,695 |  |  | $ | 3,801 |  |  | $ | 7,428 |

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