Basis of presentation (Details) - USD ($) $ in Thousands	Oct. 31, 2020	Jan. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease liabilities (included in Current portion of debt and finance leases)	$ (3,018)
Current portion of debt and finance lease liabilities	4,722	$ 2,324
Lease liabilities, noncurrent (included in Long-term debt and finance leases)	(4,589)
Long term debt and finance lease liabilities	$ 24,439	21,540
Restatement Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease liabilities (included in Current portion of debt and finance leases)		2,300
Current portion of debt and finance lease liabilities		2,300
Lease liabilities, noncurrent (included in Long-term debt and finance leases)		2,100
Long term debt and finance lease liabilities		$ 2,100

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

+ References

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- Definition

Amount of long-term debt and lease obligation, classified as noncurrent.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of long-term debt and lease obligation, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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+ References

No definition available.

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