Composition of certain financial statement captions - Schedule Of Accounts Notes Loans And Financing Receivable (Detail) - USD ($) $ in Thousands	Oct. 31, 2019	Jan. 31, 2019
Accounts Receivable Additional Disclosures [Abstract]
Billed	$ 19,759	$ 15,990
Unbilled	978	636
Total accounts receivable, gross	20,737	16,626
Less allowance for doubtful accounts	(729)	(517)
Total accounts receivable	$ 20,008	$ 16,109

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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