Intangible Assets Acquired from Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Intangible Assets [Line Items]
Accumulated Impairment	$ (30,808)	$ (30,808)
FCI and Centronix
Intangible Assets [Line Items]
Cost	25,377	25,377
Accumulated Impairment	(4,474)	(4,474)
Accumulated Amortization	(20,903)	(20,903)
Net Carrying Amount	0	0
FCI and Centronix \| Core Technology
Intangible Assets [Line Items]
Cost	15,809	15,809
Accumulated Impairment	(4,474)	(4,474)
Accumulated Amortization	(11,335)	(11,335)
Net Carrying Amount	0	0
FCI and Centronix \| Customer Relationships
Intangible Assets [Line Items]
Cost	8,325	8,325
Accumulated Amortization	(8,325)	(8,325)
Net Carrying Amount	0	0
FCI and Centronix \| Order backlog
Intangible Assets [Line Items]
Cost	1,243	1,243
Accumulated Amortization	(1,243)	(1,243)
Net Carrying Amount	$ 0	$ 0

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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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- Definition

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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