Consolidated Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) (Parenthetical) $ in Thousands	12 Months Ended
Jan. 31, 2020 USD ($)
Statement of Stockholders' Equity [Abstract]
Issuance costs	$ 326

Temporary Equity, Shares Issued During Period, Issuance Costs

No definition available.

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Namespace Prefix:	gtlb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration