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Acquisitions (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | Feb. 22, 2017 | Oct. 11, 2016
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Technology |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 10 years | 15 years
Customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life | 7 years | 11 years
Backlog |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Life |  | 3 months
Package Concierge |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired | $ 3,600 |
Package Concierge | Technology |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired | 1,300 |
Package Concierge | Customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired | 1,700 |
Package Concierge | Trademarks |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired | $ 600 |
Nexus Corporation |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired |  | $ 6,200
Nexus Corporation | Technology |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired |  | 1,300
Nexus Corporation | Customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired |  | 800
Nexus Corporation | Backlog |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired |  | 900
Nexus Corporation | Trademarks |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Fair Value, finite-lived intangible assets acquired |  | $ 3,200

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