Fair Value Measurements (Parenthetical) (Detail) (USD $)	12 Months Ended
Jan. 31, 2013	Jan. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contingent earnout, discount rate	41.20%	41.20%
Minimum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated annual revenues	1,500,000	1,500,000
Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated annual revenues	6,100,000	6,100,000

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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