Segment Reporting (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2012	Oct. 31, 2011
Segment Reporting Information [Line Items]
Revenues	$ 18,573	$ 28,020	$ 76,284	$ 75,800
Operating income (loss)	(1,862)	8,401	11,145	19,972
Income before taxes	(2,178)	9,056	10,159	19,685
Equipment Leasing [Member]
Segment Reporting Information [Line Items]
Revenues	14,078	21,822	53,983	54,719
Operating income (loss)	(2,760)	5,690	2,954	11,671
Income before taxes	(2,714)	6,007	2,378	11,717
Seamap [Member]
Segment Reporting Information [Line Items]
Revenues	4,839	6,743	23,134	22,009
Operating income (loss)	1,232	2,811	8,410	8,534
Income before taxes	870	3,149	8,000	8,201
Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(344)	(545)	(833)	(928)
Operating income (loss)	(334)	(100)	(219)	(233)
Income before taxes	$ (334)	$ (100)	$ (219)	$ (233)