Amount of lease operating expense related to property used in oil and gas production.

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=6453985&loc=d3e41499-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 10
-Paragraph a
-Subparagraph 17
-Article 4

+ 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.

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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

+ 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.

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Leases - Additional Information (Detail) - USD ($)	12 Months Ended
Leases - Additional Information (Detail) - USD ($)	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Maximum [Member]
Property, Plant and Equipment [Line Items]
Operating leases, non-cancelable term	1 year
Foreign Country [Member]
Property, Plant and Equipment [Line Items]
Office rental expense	$ 1,200,000	$ 1,400,000	$ 1,400,000
Seismic Equipment Lease Pool [Member] \| Domestic Tax Authority [Member]
Property, Plant and Equipment [Line Items]
Lease expense incurred by the Company	$ 831,000	$ 1,400,000	$ 621,000