INVESTMENTS - Summary of Contractual Maturities of Fixed Income Securities Included in Short-Term Investments (Details) (USD $) In Thousands, unless otherwise specified	May 31, 2013	Nov. 30, 2012
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	$ 63,785	$ 34,411
Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Contractual maturities, less than one year	28,831	22,733
Contractual maturities, one to three years	$ 34,954	$ 11,678

Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 320

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 20

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant