Investments (Summary Of Contractual Maturities Of Fixed Income Securities Included In Short-Term Investments) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Investments [Line Items]
Aggregate Fair Value	$ 330,331	$ 411,486
Short-Term Investments
Investments [Line Items]
Contractual maturities, Less than one year	36,084	22,733
Contractual maturities, One to three years	47,758	11,678
Aggregate Fair Value	$ 83,842	$ 34,411

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

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