Cash, Cash Equivalents and Investments (Summary of Cash, Cash Equivalents and Trading and Available-for-sale Investments by Balance Sheet Classification) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2010
Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	$ 198,818	$ 301,792	$ 161,095	$ 286,559
Short-term Investments	32,622	53,425
Long-term Investments	24,761	26,321
State And Municipal Bond Obligations [Member]
Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	0	0
Short-term Investments	31,102	50,818
Long-term Investments	0	0
Auction Rate Securities - Municipal Bonds [Member]
Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	0	0
Short-term Investments	1,520	0
Long-term Investments	21,933	23,420
Auction Rate Securities - Student Loans [Member]
Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	0	0
Short-term Investments	0	0
Long-term Investments	2,828	2,901
Corporate Bonds [Member]
Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	0	0
Short-term Investments	0	2,607
Long-term Investments	0	0
Cash [Member]
Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	144,305	176,201
Short-term Investments	0	0
Long-term Investments	0	0
Money Market Funds [Member]
Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	54,513	125,591
Short-term Investments	0	0
Long-term Investments	$ 0	$ 0