Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Paranthetical) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2018	Jan. 31, 2019
Series D
Stock issuance costs	$ 187
Series D-1
Stock issuance costs	$ 78
Series E
Stock issuance costs		$ 104

The cash outflow for cost incurred directly with the issuance of an equity security.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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