Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	Jul. 31, 2021	Jan. 31, 2021	Jan. 31, 2020
Daimler [Member]
Related Party Transaction [Line Items]
Related party accounts receivable	$ 2.5	$ 1.2	$ 0.9

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Name:	us-gaap_AccountsReceivableRelatedParties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant