Business Combination - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended
	Nov. 19, 2010	Jul. 31, 2012	Jul. 31, 2011
Business Acquisition [Line Items]
Total purchase consideration	$ 686
Cash paid	346
Contingent consideration	340
Period in which the company will generate revenue from sale of certain acquired products	2 years
Cash flow discounted rate		22.10%	22.10%
Minimum
Business Acquisition [Line Items]
Contingent consideration		120
Cash flow discounted rate		22.10%
Maximum
Business Acquisition [Line Items]
Contingent consideration		460
Cash flow discounted rate		24.10%