Net Loss per Share - Additional Information (Details)	3 Months Ended
Apr. 30, 2018 vote
Class A Common Stock
Class of Stock [Line Items]
Number of votes per share	1
Class B Common Stock
Class of Stock [Line Items]
Number of votes per share	10

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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