Long-term Debt - Summary of Long-term Debt (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Feb. 28, 2014
Debt Instrument [Line Items]
Term loan, bearing interest at variable rates	3.66%
Term loan, bearing interest at variable rates, amount	$ 0.6
Term Loan Due on 2016 [Member]
Debt Instrument [Line Items]
Maturity date	November 2016
Senior subordinated notes [Member]
Debt Instrument [Line Items]
Maturity date	March 2021
7.125% Second-Priority Senior Secured Notes [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest	7.125%
Maturity date	March 2021
Convertible Subordinated Debentures, Bearing Interest at 2.25% Maturing in November 2024 [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest	2.25%
Maturity date	November 2024
Convertible Subordinated Debentures, Bearing Interest at 4.0625% Maturing in December 2034 [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest	4.0625%
Maturity date	December 2034
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Maturity date	March 2017

Debt Instruments Maturity Date

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-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 210.5-02.22(a)(1))

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

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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Period Type:	duration

- Definition

The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

No definition available.

+ Details

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

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant