Fair Value Measurement - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 30, 2012	Jan. 31, 2012
Disclosure Fair Value Measurement Additional Information [Abstract]
Fair value of contingent consideration included in accrued liabilities	$ 772	$ 510
Fair value of contingent consideration included in other long term liabilities	4,381	5,610
Decrease in contignet consideration	(537)
Current portion of notes payable	$ 1,357	$ 1,349

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The change in the estimated liability for contingent consideration resulting in a gain or loss in the statement of operations during the reporting period.

+ References

No definition available.

+ Details

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- Definition

Current portion of the fair value as of the acquisition date of potential payments under the contingent consideration arrangement, including cash and shares as applicable.

+ References

No definition available.

+ Details

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- Definition

Noncurrent portion of the fair value as of the acquisition date of potential payments under the contingent consideration arrangement, including cash and shares as applicable.

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying values as of the balance sheet date of the portions of all long-term notes and loans payable due within one year or the operating cycle if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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