CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (unaudited) (Parenthetical) (USD $)	6 Months Ended
Jul. 31, 2011	Jul. 31, 2010
Comprehensive income:
Interest rate swap, net of tax of	$ 16,287	$ 33,778
Purchases, treasury shares (in shares)	3,717	26,895

Total tax effect of the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges after taxes. The change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 25

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