Summary of Investment (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2014	Feb. 28, 2013
Investment [Line Items]
Total investments	$ 7,181	$ 7,889
Available For Sale Securities
Investment [Line Items]
Available-for-sale investments	6,750	6,500
Texas Tower Partnership [Member]
Investment [Line Items]
Equity method investment-Texas tower partnership	0	1,389
Other Equity Method Investments [Member]
Investment [Line Items]
Equity method investment-Texas tower partnership	$ 431	$ 0

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details