v3.21.1

Debt and Finance Lease Liabilities - Additional Information (Detail) $ / shares in Units, $ in Thousands				12 Months Ended
	Apr. 10, 2020 USD ($)	Feb. 28, 2019 USD ($) $ / shares shares	Nov. 02, 2018 USD ($) installment	Jan. 31, 2021 USD ($)	Jan. 31, 2020 USD ($)	Jan. 31, 2019 USD ($)	Jul. 21, 2020	May 05, 2020 USD ($)
Debt Instrument [Line Items]
Term loan and revolving credit facility				$ 0	$ 20,000
Debt prepayment fee				0	300	$ 0
Debt extinguishment cost				$ 0	(1,073)	$ 0
Second Amended And Restated Loan And Security Agreement
Debt Instrument [Line Items]
Interest rate				4.50%
Remaining borrowing capacity				$ 50,000
Second Amended And Restated Loan And Security Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit borrowing capacity								$ 50,000
Term loan and revolving credit facility								20,663
Debt expiration period (in years)				5 years
Annual commitment fee								125
Early termination penalty								187
Monthly decrease in contract								$ 6
Termination fee percentage before year two								0.015
Termination fee percentage before year three								0.0075
Termination fee percentage before year four								0.005
Debt related fees incurred				$ 531
Debt prepayment fee				406
Line of credit entrance fee				$ 125
Second Amended And Restated Loan And Security Agreement | Revolving Credit Facility | Before EBITDA Benchmark
Debt Instrument [Line Items]
Stated interest percentage								4.50%
Second Amended And Restated Loan And Security Agreement | Revolving Credit Facility | After EBITDA Benchmark
Debt Instrument [Line Items]
Stated interest percentage				4.00%
Second Amended And Restated Loan And Security Agreement | Revolving Credit Facility | Prime Rate | After EBITDA Benchmark
Debt Instrument [Line Items]
Variable rate				0.50%
Second Amended And Restated Loan And Security Agreement Optional Capacity Increase | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit borrowing capacity								$ 65,000
Term Loan
Debt Instrument [Line Items]
Borrowing capacity		$ 20,000
Number of warrants (in shares) | shares		150,274
Exercise price (in USD per share) | $ / shares		$ 8.02
Debt extinguishment cost					$ 1,073
Term Loan | Prime Rate
Debt Instrument [Line Items]
Variable rate		1.50%
Insurance Premium Financing Agreement
Debt Instrument [Line Items]
Term loan and revolving credit facility				$ 673
Stated interest percentage							2.60%
Vendor Financing Agreement Maturing May 2023
Debt Instrument [Line Items]
Term loan and revolving credit facility				133
Stated interest percentage	2.94%
Borrowing capacity	$ 174
Periodic debt payments	$ 46
Vendor Financing Agreement Maturing June 2022
Debt Instrument [Line Items]
Term loan and revolving credit facility				$ 504
Stated interest percentage			9.83%
Borrowing capacity			$ 1,256
Periodic debt payments			$ 183
Number of debt payments | installment			3

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