Cash, Cash Equivalents and Short-Term Investments (Details 1) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012 securities	Dec. 02, 2011 securities
Fair Value and Gross Unrealized Losses Related to Available-For-Sale Securities [Abstract]
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, fair value	$ 186,321	$ 559,160
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, gross unrealized losses	(259)	(4,562)
Available-for-sale securities in a continuous unrealized loss position for more than twelve months, fair value	2,999	25,586
Available-for-sale securities in a continuous unrealized loss position for more than twelve months, gross unrealized losses	(1)	(233)
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Number of securities in a continuous unrealized loss position for less than twelve months	65	213
Number of securities in a continuous unrealized loss position for more than twelve months	1	13
Corporate bonds and commercial paper [Member]
Fair Value and Gross Unrealized Losses Related to Available-For-Sale Securities [Abstract]
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, fair value	95,489	408,178
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, gross unrealized losses	(132)	(4,438)
Available-for-sale securities in a continuous unrealized loss position for more than twelve months, fair value	2,999	22,918
Available-for-sale securities in a continuous unrealized loss position for more than twelve months, gross unrealized losses	(1)	(232)
Foreign government securities [Member]
Fair Value and Gross Unrealized Losses Related to Available-For-Sale Securities [Abstract]
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, fair value	2,105	0
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, gross unrealized losses	(12)	0
Municipal securities [Member]
Fair Value and Gross Unrealized Losses Related to Available-For-Sale Securities [Abstract]
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, fair value	40,524	17,125
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, gross unrealized losses	(60)	(3)
Available-for-sale securities in a continuous unrealized loss position for more than twelve months, fair value	0	2,668
Available-for-sale securities in a continuous unrealized loss position for more than twelve months, gross unrealized losses	0	(1)
U.S. Treasury and agency securities [Member]
Fair Value and Gross Unrealized Losses Related to Available-For-Sale Securities [Abstract]
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, fair value	48,203	133,857
Available-for-sale securities in a continuous unrealized loss position for less than twelve months, gross unrealized losses	$ (55)	$ (121)