Long-Term Debt - Carrying Amounts of Equity and Liability Components (Detail) (USD $) In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Debt Instrument [Line Items]
Carrying amount of equity component, net of equity issuance costs	$ 44.1	$ 44.1
Convertible Subordinated Debentures, Bearing Interest at 2.25% Maturing in November 2024 [Member]
Debt Instrument [Line Items]
Principal amount of 2 1/4% Debentures	$ 0.2	$ 0.2

Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_ConvertibleNotesPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant