Accounts Receivable And Allowances For Doubtful Accounts, Returns And Discounts (Schedule Of Accounts Receivable) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2011	Nov. 30, 2010	Nov. 30, 2009	Nov. 30, 2008
Accounts Receivable And Allowances For Doubtful Accounts, Returns And Discounts [Abstract]
Accounts receivable	$ 182,788	$ 178,925
Unbilled fees for professional services	19,499	12,544
Gross accounts receivable	202,287	191,469
Less: Allowances for doubtful accounts, returns and discounts	(5,868)	(5,729)	(4,224)	(4,369)
Net accounts receivable	$ 196,419	$ 185,740