Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2017	Apr. 30, 2016
Income Statement [Abstract]
Revenue	$ 64,135	$ 57,157
Cost of revenue	23,172	20,450
Gross profit	40,963	36,707
Operating expenses:
Research and development	26,602	24,466
Selling, general and administrative	11,744	10,893
Total operating expenses	38,346	35,359
Income from operations	2,617	1,348
Other income	153	27
Income before income taxes	2,770	1,375
Provision (benefit) for income taxes	206	(408)
Net income	$ 2,564	$ 1,783
Net income per share attributable to ordinary shareholders:
Basic	$ 0.08	$ 0.05
Diluted	$ 0.07	$ 0.05
Weighted-average shares used to compute net income per share attributable to ordinary shareholders:
Basic	33,253,817	32,428,047
Diluted	34,685,081	33,950,736

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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