CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) (USD $)	3 Months Ended		9 Months Ended
	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2012	Oct. 31, 2011
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) [Abstract]
Net income	$ 2,790,735	$ 2,081,886	$ 5,669,432	$ 4,984,627
Other comprehensive (loss) income net of tax:
Foreign currency translation adjustment	263,103	(266,545)	(68,473)	80,375
Interest rate swap, net of tax of ($11,182), $22,656, ($7,808) and $6,369, respectively	13,296	(10,843)	19,041	(38,576)
Other comprehensive (loss) income, net of tax	276,399	(277,388)	(49,432)	41,799
Total comprehensive income	$ 3,067,134	$ 1,804,498	$ 5,620,000	$ 5,026,426