Business Acquisitions and Discontinued Operations (Details) (USD $)	12 Months Ended			12 Months Ended			12 Months Ended				12 Months Ended				12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2013 Calgary Facility [Member]	Jan. 31, 2012 Calgary Facility [Member]	Oct. 31, 2011 Calgary Facility [Member]	Jan. 31, 2012 Ingenium Testing [Member]	Jul. 21, 2011 Ingenium Testing [Member]	Jan. 31, 2013 Ingenium Testing and Two Affiliated companies [Member]	Jul. 21, 2011 Ingenium Testing and Two Affiliated companies [Member] Company	Jan. 31, 2013 Lightning Technologies, Inc [Member]	Jan. 31, 2012 Lightning Technologies, Inc [Member]	Apr. 07, 2012 Lightning Technologies, Inc [Member]	Sep. 01, 2011 Lightning Technologies, Inc [Member]	Jan. 31, 2013 Garwood Laboratories, Inc. [Member]	Apr. 07, 2012 Garwood Laboratories, Inc. [Member]
Business Acquisition [Line Items]
Earn-out contingent consideration								$ 7,075,000					$ 1,000,000			$ 450,000
Earn-out period for additional earn-out consideration							3 years
Adjusted fair value of earn out														500,000
Acquisition-related costs incurred							350,000					40,000
Earn Out Liability, Payments											197,000
Aggregate purchase price [Abstract]
Cash paid								12,002,000						5,200,000	3,165,000
Note payable															1,175,000
Working capital adjustment paid														148,000
Working capital adjustment receivable															(198,000)
Fair value of earn-out								400,000	0		650,000				200,000
Purchase price held back														900,000	750,000
Aggregate purchase price	4,500,000							12,402,000		12,525,000				6,748,000	5,092,000
Summary of preliminarily estimated fair value at date of acquisition of acquired tangible and intangible assets and liabilities [Abstract]
Cash															49,000
Accounts receivable															593,000
Account receivable and other assets														1,062,000
Property, plant and equipment, net								8,007,000						1,702,000	3,138,000
Other assets															23,000
Intangible assets								4,200,000						3,700,000	1,200,000
Accounts payable															(157,000)
Accrued expenses															(131,000)
Relocation expense															(300,000)
Net liabilities assumed								(523,000)						(228,000)
Deferred taxes															(1,678,000)
Fair value of assets and liabilities acquired								11,684,000						6,236,000	2,737,000
Goodwill								718,000						512,000	2,355,000
Number of affiliated companies purchased										2
Estimate of working capital adjustment														100,000
Purchase Price Held Back Period, Maximum												18 months			18 months
Amortization of Acquired Intangible Assets															1,000,000
Amortized period of intangible assets acquired															10 years
Selling, general and administrative expense															76,000
Minority interest (in hundredths)	49.90%
Purchase price	4,500,000							12,402,000		12,525,000				6,748,000	5,092,000
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net book value of assets disposed of						44,000
Net book value of assets transferred to other NTS facilities						403,000
Major classes of assets and liabilities of discontinued operations [Abstract]
Cash and cash equivalents	5,000	15,000	376,000	5,000	15,000
Accounts receivable, less allowance for doubtful accounts of $15,000 at January 31,2012				0	105,000
Prepaid expenses				0	0
Property, plant, and equipment, at cost				0	0
Accumulated depreciation				0	0
Total assets of discontinued operations				5,000	120,000
Accounts payable				0	0
Accrued expenses				(33,000)	(84,000)
Total liabilities of discontinued operations				(33,000)	(84,000)
Results from discontinued operations [Abstract]
Net revenues				0	1,278,000
Cost of sales				3,000	1,305,000
Gross profit				(3,000)	(27,000)
Selling, general and administrative expenses				0	26,000
Recovery of receivable previously written off				0	(261,000)
Other expense				0	23,000
Shut down expense				0	566,000
Loss from Calgary operations				(3,000)	(381,000)
Income taxes				0	0
Loss from discontinued operations, net of tax	$ (3,000)	$ (381,000)		$ (3,000)	$ (381,000)