Segment Reporting (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2012	Jul. 31, 2011
Segment Reporting Information [Line Items]
Revenues	$ 23,080	$ 21,278	$ 57,711	$ 47,780
Operating income (loss)	1,341	2,599	13,007	11,571
Income before taxes	1,274	2,168	12,337	10,629
Equipment Leasing [Member]
Segment Reporting Information [Line Items]
Revenues	15,818	14,744	39,905	32,897
Operating income (loss)	(1,313)	632	5,714	5,981
Income before taxes	(1,634)	424	5,092	5,710
Seamap [Member]
Segment Reporting Information [Line Items]
Revenues	7,454	6,816	18,295	15,266
Operating income (loss)	2,617	2,162	7,178	5,723
Income before taxes	2,871	1,939	7,130	5,052
Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(192)	(282)	(489)	(383)
Operating income (loss)	37	(195)	115	(133)
Income before taxes	$ 37	$ (195)	$ 115	$ (133)

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

+ Details

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

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- Definition

Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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