Investments (Summary Of Contractual Maturities Of Fixed Income Securities Included In Short-Term Investments) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Nov. 30, 2011
Investments [Line Items]
Aggregate Fair Value	$ 411,486	$ 17,449
Short-Term Investments
Investments [Line Items]
Contractual maturities, Less than one year	22,733	0
Contractual maturities, One to three years	11,678	225
Aggregate Fair Value	$ 34,411	$ 225

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

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