Fair Value of Financial Assets and Liabilities - Schedule of Fair Value by Balance Sheet Location (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Jan. 31, 2021
Assets
Restricted cash: money market funds	$ 6,100	$ 5,400
Liabilities
Warrants	23,224	0
Preferred Stock Warrant \| Level 3
Liabilities
Warrants		11,359
Fair Value, Recurring \| Level 1
Assets
Cash equivalents: money market funds	470,066	50,449
Restricted cash: money market funds	5,875	5,165
Total assets	475,941	55,614
Liabilities
Convertible notes		0
Total liabilities	10,764	0
Fair Value, Recurring \| Level 2
Assets
Cash equivalents: money market funds	0	0
Restricted cash: money market funds	0	0
Total assets	0	0
Liabilities
Convertible notes		0
Total liabilities	0	0
Fair Value, Recurring \| Level 3
Assets
Cash equivalents: money market funds	0	0
Restricted cash: money market funds	0	0
Total assets	0	0
Liabilities
Convertible notes		101,212
Total liabilities	12,460	112,571
Fair Value, Recurring \| Public Warrants \| Level 1
Liabilities
Warrants	10,764
Fair Value, Recurring \| Public Warrants \| Level 2
Liabilities
Warrants	0
Fair Value, Recurring \| Public Warrants \| Level 3
Liabilities
Warrants	0
Fair Value, Recurring \| Private Placement Warrants \| Level 1
Liabilities
Warrants	0
Fair Value, Recurring \| Private Placement Warrants \| Level 2
Liabilities
Warrants	0
Fair Value, Recurring \| Private Placement Warrants \| Level 3
Liabilities
Warrants	$ 12,460
Fair Value, Recurring \| Preferred Stock Warrant \| Level 1
Liabilities
Warrants		0
Fair Value, Recurring \| Preferred Stock Warrant \| Level 2
Liabilities
Warrants		0
Fair Value, Recurring \| Preferred Stock Warrant \| Level 3
Liabilities
Warrants		$ 11,359

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value of financial and nonfinancial obligations.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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