Intangible Assets Acquired from Acquisition (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Intangible Assets [Line Items]
Accumulated Impairment	$ (30,808)	$ (30,808)
FCI, Centronix and Shannon
Intangible Assets [Line Items]
Cost	33,758	25,377
Accumulated Impairment	(4,474)	(4,474)
Accumulated Amortization	(21,954)	(20,903)
Net Carrying Amount	7,330
FCI, Centronix and Shannon \| Core Technology
Intangible Assets [Line Items]
Cost	15,809	15,809
Accumulated Impairment	(4,474)	(4,474)
Accumulated Amortization	(11,335)	(11,335)
FCI, Centronix and Shannon \| Customer Relationships
Intangible Assets [Line Items]
Cost	8,325	8,325
Accumulated Amortization	(8,325)	(8,325)
FCI, Centronix and Shannon \| Order backlog
Intangible Assets [Line Items]
Cost	1,243	1,243
Accumulated Amortization	(1,243)	$ (1,243)
FCI, Centronix and Shannon \| Development technology
Intangible Assets [Line Items]
Cost	8,381
Accumulated Amortization	(1,051)
Net Carrying Amount	$ 7,330

Intangible Assets [Line Items]

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a,h)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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