Long-term Debt - Summary of Long-term Debt (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	May 31, 2014	May 31, 2013
Debt Instrument [Line Items]
Term loan, bearing interest at variable rates	2.48%
Term loan, bearing interest at variable rates, amount	$ 1.3
Term Loan Due on 2019 [Member]
Debt Instrument [Line Items]
Maturity date	May 2019
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 2039 [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest	4.0625%	4.0625%
Maturity date	December 2039
Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Term loan, bearing interest at variable rates	9.50%
Maturity date	April 2022
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Maturity date	March 2017