Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2020	Nov. 02, 2019	Oct. 31, 2020	Nov. 02, 2019
Commitments And Contingencies Disclosure [Abstract]
Operating lease cost excluding variable lease costs and sublease income	$ 100	$ 100	$ 300	$ 400
Operating lease, Weighted-average remaining lease term	3 years 10 months 24 days		3 years 10 months 24 days
Operating lease, Weighted-average IBR	8.80%		8.80%
Operating lease, right-of-use asset	$ 1,300		$ 1,300
Remainder of Fiscal 2021	111		111
Fiscal 2022	540		540
Fiscal 2023	425		425
Fiscal 2024	434		434
Fiscal 2025	333		333
Total future minimum lease payments	1,843		1,843
Less imputed interest	(283)		(283)
Present value of operating lease liabilities	$ 1,560		$ 1,560

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 6
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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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