Goodwill and Other Intangible Assets - Summary of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 39,274	$ 40,206
Accumulated Amortization	35,892	34,429
Total	3,382us-gaap_FiniteLivedIntangibleAssetsNet	5,777us-gaap_FiniteLivedIntangibleAssetsNet
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	32,995	33,927
Accumulated Amortization	29,613	28,552
Total	3,382	5,375
Research Content [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,699	4,699
Accumulated Amortization	4,699	4,699
Total	0
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,507	1,507
Accumulated Amortization	1,507	1,105
Total	0	402
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	73	73
Accumulated Amortization	73	73
Total	$ 0

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

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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