Long-term Debt - Schedule of Long-term Debt (Details) (USD $)	12 Months Ended
	Feb. 28, 2013	Feb. 29, 2012
Debt Instrument [Line Items]
Total	$ 210,714,000	$ 225,000,000
Less amount due within one year	(14,286,000)	(14,286,000)
Long-term debt, exculding current maturities	196,428,571	210,714,286
Senior Notes [Member] | Unsecured Senior Notes Due January 2021 [Member]
Debt Instrument [Line Items]
Total	125,000,000	125,000,000
Senior Notes [Member] | Unsecured Senior Notes Due March 2012 through March 2018 [Member]
Debt Instrument [Line Items]
Total	85,714,000	100,000,000
Annual installments	14,285,714
Line of Credit [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Total	$ 0	$ 0