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Goodwill and Related Intangible Assets (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
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Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | $ 125,361 | $ 108,527
Total acquired intangible assets, Gross Carrying Amount | 176,656 | 154,297
Accumulated Amortization, Finite-lived intangible assets | 66,175 | 61,705
Total acquired intangible assets, Accumulated Amortization | 66,175 | 61,705
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 6,753 | 6,139
Accumulated Amortization, Finite-lived intangible assets | 4,328 | 4,105
Unpatented technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 35,383 | 29,544
Accumulated Amortization, Finite-lived intangible assets | 17,031 | 15,807
Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 80,976 | 71,195
Accumulated Amortization, Finite-lived intangible assets | 42,876 | 40,294
Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 1,949 | 1,649
Accumulated Amortization, Finite-lived intangible assets | 1,640 | 1,499
Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 300 | 0
Accumulated Amortization, Finite-lived intangible assets | 300 | 0
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Indefinite-lived intangible assets | 51,295 | 45,770
Accumulated Amortization, Indefinite-lived intangible assets | $ 0 | $ 0

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