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Goodwill and Related Intangible Assets (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | $ 113,646 | $ 128,939
Total acquired intangible assets, Gross Carrying Amount | 158,366 | 179,477
Accumulated Amortization, Finite-lived intangible assets | 47,576 | 56,464
Total acquired intangible assets, Accumulated Amortization | 47,576 | 56,464
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 5,808 | 5,861
Accumulated Amortization, Finite-lived intangible assets | 2,427 | 1,884
Unpatented technology and patents |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 26,720 | 28,072
Accumulated Amortization, Finite-lived intangible assets | 10,041 | 10,656
Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 78,569 | 85,419
Accumulated Amortization, Finite-lived intangible assets | 33,585 | 35,673
Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 1,649 | 3,107
Accumulated Amortization, Finite-lived intangible assets | 623 | 1,771
Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 900 | 6,480
Accumulated Amortization, Finite-lived intangible assets | 900 | 6,480
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Indefinite-lived intangible assets | 44,720 | 50,538
Accumulated Amortization, Indefinite-lived intangible assets | $ 0 | $ 0
Minimum | Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 5 years |
Minimum | Unpatented technology and patents |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 5 years |
Minimum | Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 5 years |
Minimum | Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 4 years |
Minimum | Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 6 months |
Maximum | Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 15 years |
Maximum | Unpatented technology and patents |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 20 years |
Maximum | Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 17 years |
Maximum | Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 10 years |
Maximum | Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 2 years |

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