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COMMITMENTS - Leases (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Jan. 31, 2020 | Jan. 31, 2019 | Jan. 31, 2018
Commitments |  |  |
Lease, practical expedients | true |  |
Operating leases, options to extend | true |  |
Operating leases, options to terminate | true |  |
Operating lease payments made | $ 1,000 |  |
Weighted average lease term | 33 months |  |
Operating lease expense | $ 1,004 |  |
Weighted average discount rate | 4.10% |  |
Right-of-use assets | $ 2,408 | $ 290 |
Lease liabilities | 636 |  |
April 30, 2021 | 1,239 |  |
December 31, 2023 | 246 |  |
Costs of Revenues |  |  |
Commitments |  |  |
Rent incurred on construction projects included in the costs of revenues | 4,000 | 11,400 | $ 20,300
Selling, General and Administrative Expenses |  |  |
Commitments |  |  |
Rent expense included in selling, general and administrative expenses of continuing operations | 700 | $ 700 | $ 700
TRC |  |  |
Commitments |  |  |
April 30, 2021 | 300 |  |
APC |  |  |
Commitments |  |  |
December 31, 2023 | 100 |  |
GPS | Financial guarantee |  |  |
Commitments |  |  |
Guarantor obligation maximum exposure | $ 3,600 |  |
London Interbank Offered Rate (LIBOR) |  |  |
Commitments |  |  |
Interest rate margin on referred rate | 2.00% |  |

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- Definition Indicates (true false) whether practical expedients are elected for not reassessing whether any expired or existing contract is or contains lease, lease classification for expired or existing lease, and initial direct cost for any existing lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=113997351&loc=SL77916155-209984 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=113997351&loc=SL77916155-209984 + Details
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