Debt Capital leases (Details) - USD ($)	12 Months Ended
Jan. 31, 2017	Jan. 31, 2016
Debt Instrument [Line Items]
Capitalized lease obligations	$ 283,000	$ 442,000
Piping [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	May 01, 2012
Debt Instrument, Face Amount	$ 400,000
Debt Instrument, Interest Rate at Period End	6.50%
Debt Instrument, Periodic Payment	$ 8,000
Debt Instrument, Maturity Date	Jun. 01, 2017
Indian capital leases [Member]
Debt Instrument [Line Items]
Capitalized lease obligations	$ 8,000
Debt instrument, interest rate, stated percentage range, minimum	15.60%
Debt Instrument, Issuance Date	Aug. 05, 2016
Face value of debt in local currency	0.6 million Indian Rupees
Debt Instrument, Periodic Payment	$ 270
Debt Instrument, Maturity Date	Jul. 05, 2019
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Capitalized lease obligations	$ 41,000
Debt Instrument, Issuance Date	Feb. 01, 2013
Debt Instrument, Interest Rate at Period End	4.00%
Debt Instrument, Periodic Payment	$ 1,000
Debt Instrument, Maturity Date	Nov. 30, 2017
Leases, Acquired-in-Place [Member]
Debt Instrument [Line Items]
Capitalized lease obligations	$ 728,000
Debt Instrument, Issuance Date	Mar. 12, 2013
Debt Instrument, Interest Rate at Period End	4.00%
Debt Instrument, Periodic Payment	$ 12,000
Debt Instrument, Maturity Date	Mar. 11, 2017
Capital Addition Purchase Commitments [Member]
Debt Instrument [Line Items]
Capitalized lease obligations	$ 942,000
Debt Instrument, Issuance Date	Jun. 26, 2014
Debt Instrument, Interest Rate at Period End	3.25%
Debt Instrument, Periodic Payment	$ 14,000
Debt Instrument, Maturity Date	Jun. 25, 2018
Vehicles [Member]
Debt Instrument [Line Items]
Capitalized lease obligations	$ 52,000
Debt Instrument, Issuance Date	Jul. 01, 2014
Debt Instrument, Interest Rate at Period End	3.25%
Debt Instrument, Periodic Payment	$ 1,000
Debt Instrument, Maturity Date	Jun. 30, 2018

Face value of debt in local currency

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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