Summary of Marketable Securities which are Classified as Available-for-Sale (Detail) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012	Nov. 30, 2011
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 364,021	$ 17,424
Gross Unrealized Gains	51	51
Gross Unrealized Losses	(42)	(26)
Aggregate Fair Value	364,030	17,449
Money market funds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	363,251	16,664
Aggregate Fair Value	363,251	16,664
Term deposits
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	583	560
Aggregate Fair Value	583	560
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	187	200
Gross Unrealized Gains	51	51
Gross Unrealized Losses	(42)	(26)
Aggregate Fair Value	$ 196	$ 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