Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Apr. 30, 2020	Jan. 31, 2020	Apr. 30, 2019
Statement Of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 6,304	$ 880	$ 892
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	97,777,322	97,976,815	103,599,364
Common shares, shares outstanding	97,777,322	97,976,815	103,599,364

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

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