Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Business Acquisitions - Identifiable Intangible Assets - Aesynt (Details) - USD ($) $ in Thousands				3 Months Ended		6 Months Ended	12 Months Ended
	Jan. 05, 2016	Apr. 30, 2015	Apr. 21, 2015	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2016	Dec. 31, 2015
Identifiable Intangible Assets
Total purchased intangible assets		$ 14,051
Aesynt Holding, L.P., Aesynt, Ltd.
Business Acquisition [Line Items]
Acquisition-related costs	$ 8,000
Identifiable Intangible Assets
Total purchased intangible assets	123,700
Aesynt Holding, L.P., Aesynt, Ltd. \| In-process research and development (IPR&D) (1)
Identifiable Intangible Assets
Indefinite-lived Intangible Assets Acquired	3,900
Aesynt Holding, L.P., Aesynt, Ltd. \| Customer relationships
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased	$ 58,200
Aesynt Holding, L.P., Aesynt, Ltd. \| Customer relationships \| Minimum
Identifiable Intangible Assets
Weighted average useful life (in years)	14 years
Aesynt Holding, L.P., Aesynt, Ltd. \| Customer relationships \| Maximum
Identifiable Intangible Assets
Weighted average useful life (in years)	16 years
Aesynt Holding, L.P., Aesynt, Ltd. \| Developed technology
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased	$ 38,800
Weighted average useful life (in years)	8 years
Aesynt Holding, L.P., Aesynt, Ltd. \| Backlog
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased	$ 20,200
Aesynt Holding, L.P., Aesynt, Ltd. \| Backlog \| Minimum
Identifiable Intangible Assets
Weighted average useful life (in years)	1 year
Aesynt Holding, L.P., Aesynt, Ltd. \| Backlog \| Maximum
Identifiable Intangible Assets
Weighted average useful life (in years)	3 years
Aesynt Holding, L.P., Aesynt, Ltd. \| Non-compete
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased	$ 1,800
Weighted average useful life (in years)	3 years
Aesynt Holding, L.P., Aesynt, Ltd. \| Trade names
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased	$ 800
Weighted average useful life (in years)	1 year
Mach4
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased			$ 7,710
Total purchased intangible assets			7,710
Mach4 \| Customer relationships
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased			$ 3,570
Weighted average useful life (in years)			10 years
Mach4 \| Developed technology
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased			$ 3,290
Weighted average useful life (in years)			8 years
Mach4 \| Trade names
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased			$ 850
Weighted average useful life (in years)			6 years
Avantec
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased		6,341
Total purchased intangible assets		6,341
Avantec \| Customer relationships
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased		$ 5,834
Weighted average useful life (in years)		12 years
Avantec \| Backlog
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased		$ 415
Weighted average useful life (in years)		2 years
Avantec \| Trade names
Identifiable Intangible Assets
Fair value of identifiable intangible assets purchased		$ 92
Weighted average useful life (in years)		2 years
Selling, General and Administrative Expenses \| Aesynt Holding, L.P., Aesynt, Ltd.
Business Acquisition [Line Items]
Acquisition-related costs				$ 5,100	$ 2,900	$ 5,100	$ 2,900