Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) (USD $)	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Other Intangibles [Line Items]
Finite-lived intangible assets, Gross Value	$ 8,937,000	$ 8,930,000
Finite-lived intangible assets, Accumulated Amortization	6,866,000	6,814,000
Finite-lived intangible assets, Net Value	2,071,000us-gaap_FiniteLivedIntangibleAssetsNet	2,116,000us-gaap_FiniteLivedIntangibleAssetsNet
Other intangible assets, Gross	10,609,000	10,602,000
Other intangible assets, net	3,743,000	3,788,000
Trademarks [Member]
Other Intangibles [Line Items]
Indefinite-lived intangible assets, Net Value	1,672,000	1,672,000
Customer Relationships [Member]
Other Intangibles [Line Items]
Finite-lived intangible assets, Gross Value	5,378,000	5,378,000
Finite-lived intangible assets, Accumulated Amortization	3,892,000	3,858,000
Finite-lived intangible assets, Net Value	1,486,000	1,520,000
Customer Relationships [Member] \| Maximum [Member]
Other Intangibles [Line Items]
Amortizable Life (Years)	10 years
Customer Relationships [Member] \| Minimum [Member]
Other Intangibles [Line Items]
Amortizable Life (Years)	5 years
Developed Technology [Member]
Other Intangibles [Line Items]
Finite-lived intangible assets, Gross Value	1,980,000	1,980,000
Finite-lived intangible assets, Accumulated Amortization	1,728,000	1,719,000
Finite-lived intangible assets, Net Value	252,000	261,000
Developed Technology [Member] \| Maximum [Member]
Other Intangibles [Line Items]
Amortizable Life (Years)	6 years
Developed Technology [Member] \| Minimum [Member]
Other Intangibles [Line Items]
Amortizable Life (Years)	5 years
Trademarks [Member]
Other Intangibles [Line Items]
Finite-lived intangible assets, Gross Value	60,000	60,000
Finite-lived intangible assets, Accumulated Amortization	18,000	13,000
Finite-lived intangible assets, Net Value	42,000	47,000
Amortizable Life (Years)	2 years
Non-compete Agreements [Member]
Other Intangibles [Line Items]
Finite-lived intangible assets, Gross Value	11,000	11,000
Finite-lived intangible assets, Accumulated Amortization	1,000	1,000
Finite-lived intangible assets, Net Value	10,000	10,000
Amortizable Life (Years)	5 years
Patents [Member]
Other Intangibles [Line Items]
Finite-lived intangible assets, Gross Value	1,508,000	1,501,000
Finite-lived intangible assets, Accumulated Amortization	1,227,000	1,223,000
Finite-lived intangible assets, Net Value	$ 281,000	$ 278,000
Patents [Member] \| Maximum [Member]
Other Intangibles [Line Items]
Amortizable Life (Years)	20 years
Patents [Member] \| Minimum [Member]
Other Intangibles [Line Items]
Amortizable Life (Years)	5 years

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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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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.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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+ 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 (b)

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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-Publisher FASB

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