Balance Sheet - Accounts Receivable (Detail) - USD ($) $ in Thousands	Apr. 30, 2019	Jan. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Current accounts receivable	$ 14,401	$ 14,195
Long-term accounts receivable	465	712
Accounts receivable	14,866	14,907
Less current portion of allowance for doubtful accounts	(2,113)	(2,113)
Less long-term portion of allowance for doubtful accounts	0	0
Less total allowance for doubtful accounts	(2,113)	(2,113)
Current accounts receivable, net of allowance for doubtful accounts	12,288	12,082
Long-term accounts receivable, net of allowance for doubtful accounts	465	712
Total accounts receivable, net of allowance for doubtful accounts	$ 12,753	$ 12,794