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Goodwill and Related Intangible Assets (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Jun. 30, 2015 | Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | $ 129,964 | $ 84,524
Total acquired intangible assets, Gross Carrying Amount | 185,507 | 127,244
Accumulated Amortization, Finite-lived intangible assets | 48,776 | 45,029
Total acquired intangible assets, Accumulated Amortization | 48,776 | 45,029
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 6,520 | 3,886
Accumulated Amortization, Finite-lived intangible assets | 2,128 | 1,827
Unpatented technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 28,077 | 24,527
Accumulated Amortization, Finite-lived intangible assets | 9,676 | 8,768
Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 85,792 | 52,974
Accumulated Amortization, Finite-lived intangible assets | 33,156 | 31,554
Non-compete agreements |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 3,107 | 1,807
Accumulated Amortization, Finite-lived intangible assets | 1,617 | 1,550
Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Finite-lived intangible assets | 6,468 | 1,330
Accumulated Amortization, Finite-lived intangible assets | 2,199 | 1,330
Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount, Indefinite-lived intangible assets | 55,543 | 42,720
Accumulated Amortization, Indefinite-lived intangible assets | $ 0 | $ 0
Minimum | Trademarks |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 2 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 |
Minimum | Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 6 months |
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 |
Maximum | Backlog |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Life | 2 years |

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