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Goodwill and Related Intangible Assets (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | $ 111,287 | $ 106,806
Total acquired intangible assets, Gross Carrying Amount | 156,057 | 150,676
Accumulated Amortization, Finite-lived intangible assets | 59,872 | 54,301
Total acquired intangible assets, Accumulated Amortization | 59,872 | 54,301
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 6,122 | 6,094
Accumulated Amortization, Finite-lived intangible assets | 3,954 | 3,518
Unpatented technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 29,444 | 28,644
Accumulated Amortization, Finite-lived intangible assets | 15,301 | 13,881
Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 74,072 | 70,419
Accumulated Amortization, Finite-lived intangible assets | 39,187 | 35,678
Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 1,649 | 1,649
Accumulated Amortization, Finite-lived intangible assets | 1,430 | 1,224
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Indefinite-lived intangible assets | 44,770 | 43,870
Accumulated Amortization, Indefinite-lived intangible assets | $ 0 | $ 0
Minimum | Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 3 years |
Minimum | Unpatented technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 5 years |
Minimum | Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 5 years |
Minimum | Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 4 years |
Maximum | Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 15 years |
Maximum | Unpatented technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 20 years |
Maximum | Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 17 years |
Maximum | Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 10 years |

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