Aggregate Amortization Expense Related to Purchased Technology and Other Intangible Assets (Detail) (Purchased Technology And Other Intangible Asset, USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2012
Purchased Technology And Other Intangible Asset
Goodwill and Intangible Assets Disclosure [Line Items]
2013	$ 13,624
2014	7,378
2015	5,029
2016	1,971
2017	567
Thereafter
Aggregate amortization expense	$ 28,569

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The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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- Definition

The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fifth succeeding fiscal year.

+ References

No definition available.

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- Definition

The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

+ References

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- Definition

The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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