Balance Sheet Accounts - Estimated Fair Value and Principal Amount of Outstanding Debt (Detail) (USD $) In Millions, unless otherwise specified	Aug. 31, 2014	Nov. 30, 2013
Debt Instrument [Line Items]
Fair Value	$ 961.0	$ 938.6
Principal Amount	783.5	699.2
Term Loan [Member]
Debt Instrument [Line Items]
Fair Value	100.0	45.0
Principal Amount	100.0	45.0
7.125% Second-Priority Senior Secured Notes [Member]
Debt Instrument [Line Items]
Fair Value	495.9	494.5
Principal Amount	460.0	460.0
4.0625% Convertible Subordinated Debentures [Member]
Debt Instrument [Line Items]
Fair Value	275.2	398.1
Principal Amount	133.6	193.2
Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Fair Value	89.0	0
Principal Amount	89.0	0
Other Debt [Member]
Debt Instrument [Line Items]
Fair Value	0.9	1.0
Principal Amount	$ 0.9	$ 1.0