Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Apr. 30, 2021	Jan. 31, 2021	Apr. 30, 2020
Statement Of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 2,155	$ 4,028	$ 6,304
Preferred shares, par value	$ 0.0001	$ 0.0001	$ 0.0001
Preferred shares, shares authorized	10,000,000	10,000,000	10,000,000
Preferred shares, shares issued	0	0	0
Common shares, par value	$ 0.0001	$ 0.0001	$ 0.0001
Common shares, shares authorized	200,000,000	200,000,000	200,000,000
Common shares, shares issued	98,235,127	97,815,985	97,777,322
Common shares, shares outstanding	98,235,127	97,815,985	97,777,322

Amount of allowance for credit loss on accounts receivable, classified as current.

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