Acquisitions (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands	Feb. 22, 2017	Oct. 11, 2016
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