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Business Combinations, Goodwill and Intangible Assets, Business Combinations (Details) - USD ($) $ in Millions | Sep. 19, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
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Business Combination Segment Allocation [Line Items] |  |  |  |
Goodwill |  | $ 62.4 | $ 62.4 | $ 37.2
Imperial Machine and Tool Co. (''IMT'') [Member] |  |  |  |
Business Combination Segment Allocation [Line Items] |  |  |  |
Purchase price, net of cash acquired | $ 43.2 |  |  |

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