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Goodwill and Related Intangible Assets (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | $ 116,155 | $ 113,646
Total acquired intangible assets, Gross Carrying Amount | 161,507 | 158,366
Accumulated Amortization, Finite-lived intangible assets | 51,182 | 47,576
Total acquired intangible assets, Accumulated Amortization | 51,182 | 47,576
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 5,842 | 5,808
Accumulated Amortization, Finite-lived intangible assets | 2,749 | 2,427
Unpatented technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 28,020 | 26,720
Accumulated Amortization, Finite-lived intangible assets | 11,030 | 10,041
Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 80,644 | 78,569
Accumulated Amortization, Finite-lived intangible assets | 36,626 | 33,585
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 | 777 | 623
Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 0 | 900
Accumulated Amortization, Finite-lived intangible assets | $ 0 | 900
Estimated Life | 3 months |
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Indefinite-lived intangible assets | $ 45,352 | 44,720
Accumulated Amortization, Indefinite-lived intangible assets | $ 0 | $ 0
Minimum | Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 5 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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