Investments (Summary Of Marketable Securities Classified As Available-For-Sale) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Nov. 30, 2011
Investments [Line Items]
Purchased/Amortized Cost	$ 411,461	$ 17,424
Gross Unrealized Gains	87	51
Gross Unrealized Losses	(62)	(26)
Aggregate Fair Value	411,486	17,449
Money market funds
Investments [Line Items]
Purchased/Amortized Cost	376,480	16,664
Aggregate Fair Value	376,480	16,664
Corporate bonds and Commercial paper
Investments [Line Items]
Purchased/Amortized Cost	24,558
Gross Unrealized Gains	9
Gross Unrealized Losses	(9)
Aggregate Fair Value	24,558
U.S Government debt and agency securities
Investments [Line Items]
Purchased/Amortized Cost	9,646
Gross Unrealized Gains	0
Gross Unrealized Losses	(1)
Aggregate Fair Value	9,645
Term deposits
Investments [Line Items]
Purchased/Amortized Cost	595	560
Aggregate Fair Value	595	560
Mortgage-backed securities
Investments [Line Items]
Purchased/Amortized Cost	182	200
Gross Unrealized Gains	78	51
Gross Unrealized Losses	(52)	(26)
Aggregate Fair Value	$ 208	$ 225

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

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+ Details

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References+ Details

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References+ Details