Net Carrying Values of Debt Securities by Contractual Maturity (Detail) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012
Available-for-Sale Securities, amortized cost
Less than one year, amortized cost	$ 1,627
One year through five years, amortized cost	28,849
Six years through ten years, amortized cost	4,672
After ten years, amortized cost	1,680
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	36,828
Available-for-Sale Securities, fair value
Less than one year, fair value	1,626
One year through five years, fair value	29,096
Six years through ten years, fair value	4,888
After ten years, fair value	1,943
Available-for-sale Securities, Debt Securities, Total	$ 37,553

Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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