Summary of Significant Accounting Policies - Estimated Fair Value and Principal Amount of Long-Term Debt (Detail) (USD $) In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Fair Values Of Financial Instruments [Line Items]
Fair Value	$ 938.6	$ 294.7
Principal Amount	699.2	248.7
Term Loan [Member]
Fair Values Of Financial Instruments [Line Items]
Fair Value	45.0	47.5
Principal Amount	45.0	47.5
7.125% Second-Priority Senior Secured Notes [Member]
Fair Values Of Financial Instruments [Line Items]
Fair Value	494.5
Principal Amount	460.0
4.0625% Convertible Subordinated Debentures [Member]
Fair Values Of Financial Instruments [Line Items]
Fair Value	398.1	246.0
Principal Amount	193.2	200.0
Other Debt [Member]
Fair Values Of Financial Instruments [Line Items]
Fair Value	1.0	1.2
Principal Amount	$ 1.0	$ 1.2