FAIR VALUE DISCLOSURES (Details) (USD $)	Jul. 31, 2012	Jan. 31, 2012	Jul. 31, 2011	Jan. 31, 2011
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 31,173,910	$ 34,581,394	$ 29,721,241	$ 32,400,814
Cash	8,255,107
Money market funds	22,918,803
Number of financial institutions	20
Short-term investments [Abstract]
Certificates of deposit, short-term	1,022,266	764,061
Schedule of Short Term Investments, by Maturity [Line Items]
Number of certificates of deposit	4
Period from inception to maturity (in months)	12 months
Long-term investments [Abstract]
Certificates of deposit	246,473	494,537
Number of certificates of deposit	1	2
Period from inception to maturity (in months)	15 months
Period from inception to maturity, minimum (in months)		14 months
Period from inception to maturity, maximum (in months)		15 months
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	31,173,910	34,581,394
Short-term investments	1,022,266	764,061
Long-term investments	246,473	494,537
Cash surrender value - life insurance policies	1,147,287	1,089,989
Interest rate swap agreement	(357,167)	(366,286)
Total financial assets (liabilities)	33,232,769	36,563,695
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	31,173,910	34,581,394
Short-term investments	1,022,266	764,061
Long-term investments	246,473	494,537
Cash surrender value - life insurance policies	0	0
Interest rate swap agreement	0	0
Total financial assets (liabilities)	32,442,649	35,839,992
Significant Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Short-term investments	0	0
Long-term investments	0	0
Cash surrender value - life insurance policies	1,147,287	1,089,989
Interest rate swap agreement	(357,167)	(366,286)
Total financial assets (liabilities)	790,120	723,703
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Short-term investments	0	0
Long-term investments	0	0
Cash surrender value - life insurance policies	0	0
Interest rate swap agreement	0	0
Total financial assets (liabilities)	0	0
Estimated fair value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	3,443,543	3,747,061
Carrying amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	$ 3,047,004	$ 3,345,187
First Maturity Period [Member]
Schedule of Short Term Investments, by Maturity [Line Items]
Number of certificates of deposit		2
Period from inception to maturity (in months)		9 months
Second Maturity Period [Member]
Schedule of Short Term Investments, by Maturity [Line Items]
Number of certificates of deposit		1
Period from inception to maturity (in months)		12 months