Debt and Finance Lease Liabilities - Additional information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Debt Disclosure [Abstract]
Interest expense, net	$ 467	$ 219	$ 1,206	$ 1,769
Amortization of debt discount	74	147	318	412
Interest expense	471	557	1,305	2,142
Interest income	$ 5	$ 338	$ 99	$ 373

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The net amount of operating interest income (expense).

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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