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Leases - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Jan. 31, 2018 | Jan. 31, 2017 | Jan. 31, 2016
Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Operating leases, non-cancelable term | 1 year |  |
Foreign Country |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Office rental expense | $ 1,200 | $ 1,200 | $ 1,200
Seismic Equipment Lease Pool | Domestic Tax Authority |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Lease expense incurred by the Company | $ 774 | $ 552 | $ 831

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- Definition Amount of lease operating expense related to property used in oil and gas production. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(a)(20)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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- Definition Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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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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