Goodwill and Identified Intangible Assets - Summary of Goodwill and Identified Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	221,704	$ 221,704
Accumulated Amortization	(211,105)	(190,585)
Total	10,599us-gaap_FiniteLivedIntangibleAssetsNet	31,119us-gaap_FiniteLivedIntangibleAssetsNet
Developed core technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	136,145	136,145
Accumulated Amortization	(135,426)	(121,681)
Total	719	14,464
Developed core technology [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years
Developed core technology [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	6 years
Customer relationships/contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	67,098	67,098
Accumulated Amortization	(58,784)	(53,772)
Total	8,314	13,326
Customer relationships/contracts [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years
Customer relationships/contracts [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	6 years
Trademarks and tradenames [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	11,361	11,361
Accumulated Amortization	(11,361)	(10,565)
Total	0	796
Trademarks and tradenames [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years
Trademarks and tradenames [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years
Maintenance agreements and related relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,100	7,100
Accumulated Amortization	(5,534)	(4,567)
Total	1,566	$ 2,533
Maintenance agreements and related relationships [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	6 years
Maintenance agreements and related relationships [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

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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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