Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Oct. 31, 2019	Jan. 31, 2019	Oct. 31, 2018
Statement Of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 1,084	$ 1,499	$ 1,572
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	97,975,343	105,642,283	107,638,846
Common shares, shares outstanding	97,975,343	105,642,283	107,638,846

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

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