EARNINGS PER SHARE COMPUTATIONS (Details) (USD $)	3 Months Ended								12 Months Ended
	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Numerator [Abstract]
Net income	$ 2,375,791	$ 2,790,735	$ 1,619,999	$ 1,258,698	$ 2,149,074	$ 2,081,886	$ 1,490,234	$ 1,412,507	$ 8,045,223	$ 7,133,701	$ 6,139,132
Denominator [Abstract]
Weighted average common shares outstanding during the period for basic computation (in shares)									14,685,038	14,662,055	14,629,215
Dilutive effect of stock-based compensation plans (in shares)									52,997	112,637	129,444
Weighted average common shares outstanding during the period for diluted computation (in shares)									14,738,035	14,774,692	14,758,659
Earnings per share, basic (in dollars per share)	$ 0.16	$ 0.19	$ 0.11	$ 0.09	$ 0.15	$ 0.14	$ 0.10	$ 0.10	$ 0.55	$ 0.49	$ 0.42
Earnings per share, diluted (in dollars per share)	$ 0.16	$ 0.19	$ 0.11	$ 0.09	$ 0.15	$ 0.14	$ 0.10	$ 0.10	$ 0.55	$ 0.48	$ 0.42
Employee stock options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted earnings per share (in shares)									653,634	616,585	642,585