Long-term Debt - Summary of Long-term Debt (Details) - USD ($) $ in Millions	May. 31, 2015	Nov. 30, 2014
Debt Instrument [Line Items]
Total senior debt	$ 96.3	$ 98.8
Total senior secured notes	460.0	460.0
Convertible subordinated debentures, bearing interest at 4.0625% per annum, interest payments due in June and December, maturing in December 2039	98.0	133.8
Total convertible subordinated notes	98.0	133.8
Capital lease, payable in monthly installments, maturing in March 2017	0.6	0.6
Total other debt	63.6	89.6
Total debt	717.9	782.2
Less: Amounts due within one year	(5.3)	(5.3)
Total long-term debt	712.6	776.9
Term Loan [Member]
Debt Instrument [Line Items]
Total senior debt	96.3	98.8
Total debt	96.3	98.8
7.125% Second-Priority Senior Secured Notes [Member]
Debt Instrument [Line Items]
Total senior secured notes	460.0	460.0
Total debt	460.0	460.0
2.25% Convertible Subordinated Debentures [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest at 2.25% per annum, interest payments due in May and November, maturing in November 2024	0.2	0.2
4 1/16% Convertible Subordinated Debentures [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest at 4.0625% per annum, interest payments due in June and December, maturing in December 2039	97.8	133.6
Total debt	97.8	133.6
Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Delayed draw term loan, bearing interest at variable rates (rate of 9.50% as of May 31, 2015), maturing in April 2022	63.0	89.0
Total debt	$ 63.0	$ 89.0