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Acquisition - Additional Information (Details) | Oct. 01, 2018 USD ($) Employee t | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
--- | --- | --- | ---
Business Acquisition [Line Items] |  |  |
Goodwill |  | $ 151,918,000 | $ 153,463,000
Intangible assets, net |  | 89,886,000 | $ 93,614,000
G P Business [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Business acquisition purchase price | $ 186,000,000 |  |
Business acquisition, date of completion | Oct. 01, 2018 |  |
Post-closing purchase price adjustments | $ 2,000,000 |  |
Annual production capacity | t | 32,000 |  |
Number of employees at manufacturing facility | Employee | 220 |  |
Goodwill |  | 75,349,000 |
Intangible assets, net |  | 43,600,000 |
Goodwill deductible for tax purposes |  | $ 0 |

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