Debt (Details) - USD ($)	Mar. 11, 2020	Mar. 05, 2020	Mar. 16, 2016	Jan. 31, 2020	Apr. 30, 2019	Jan. 31, 2019	Jan. 31, 2018
Line of Credit Facility [Line Items]
Restricted cash				$ 12,100,000		$ 0	$ 0
Line of Credit | Letter of Credit
Line of Credit Facility [Line Items]
Debt instrument, collateral amount				6,900,000
Line of Credit | Letter of Credit | Subsequent Event
Line of Credit Facility [Line Items]
Borrowing capacity	$ 30,000,000.0
Line of Credit | Swingline Loan | Subsequent Event
Line of Credit Facility [Line Items]
Borrowing capacity	10,000,000.0
Line of Credit | Silicon Valley Bank
Line of Credit Facility [Line Items]
Covenant terms, minimum adjusted quick ratio			0.000125
Line of Credit | Silicon Valley Bank | Revolving Credit Line
Line of Credit Facility [Line Items]
Borrowing capacity			$ 15,000,000.0
Commitment fee, percentage			0.25%
Remaining borrowing capacity				15,000,000.0
Line of Credit | Silicon Valley Bank | Letter of Credit
Line of Credit Facility [Line Items]
Borrowing capacity				$ 7,000,000.0
Commitment fee, percentage			1.75%
Line of Credit | Prime Rate | Silicon Valley Bank | Revolving Credit Line
Line of Credit Facility [Line Items]
Basis spread on variable rate			0.50%
Secured Debt | Revolving Credit Line | Subsequent Event
Line of Credit Facility [Line Items]
Borrowing capacity	$ 50,000,000.0
Debt instrument, term	3 years
Incremental borrowing available under certain conditions	$ 50,000,000.0
Covenant terms, minimum adjusted quick ratio		0.015%
Capital stock of foreign subsidiary, percent	66.00%
Secured Debt | Letter of Credit
Line of Credit Facility [Line Items]
Borrowing capacity					$ 12,100,000
Restricted cash					$ 12,100,000
Secured Debt | London Interbank Offered Rate (LIBOR) | Revolving Credit Line | Subsequent Event | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.50%
Secured Debt | London Interbank Offered Rate (LIBOR) | Revolving Credit Line | Subsequent Event | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate	3.00%
Secured Debt | Base Rate | Revolving Credit Line | Subsequent Event | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.50%
Secured Debt | Base Rate | Revolving Credit Line | Subsequent Event | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.00%