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Inventories (Tables) | 12 Months Ended
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Dec. 31, 2019
Inventory Disclosure [Abstract] |
Schedule of Inventories | Inventories at December 31 consisted of the following (in thousands):
| 2019 |  | 2018
Raw material | $ | 45,700 |  |  | $ | 57,845 |
Work-in-process | 5,988 |  |  | 6,930 |
Finished goods | 26,788 |  |  | 34,138 |
Total inventories | $ | 78,476 |  |  | $ | 98,913 |
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):
| 2019 |  | 2018 |  | 2017
Beginning balance | $ | 4,172 |  |  | $ | 3,695 |  |  | $ | 3,801 |
Excess, obsolete and slow moving inventory expense | 659 |  |  | 729 |  |  | 1,276 |
Scrapped inventory and other adjustments | (639 | ) |  | (252 | ) |  | (1,382 | )
Ending balance | $ | 4,192 |  |  | $ | 4,172 |  |  | $ | 3,695 |

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