Debt and Finance Lease Liabilities - Additional information (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Debt Disclosure [Abstract]
Interest expense, net	$ 419	$ 745	$ 739	$ 1,549
Amortization of debt discount	119	157	245	265
Interest expense	421	781	833	1,585
Interest income	$ (2)	$ (36)	$ (94)	$ (36)

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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