Description of Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	Jul. 31, 2021	Jan. 31, 2021
Description of Organization, Business Operations and Basis of Presentation (Details) [Line Items]
Accumulated deficit	$ (682,063)	$ (679,414)
Cash equivalents and restricted cash	$ 618,500

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant