Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Feb. 28, 2014	Feb. 28, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1.4	$ 3.2
Stock Appreciation Rights [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	(0.1)	2.5
Restricted Stock, Service-Based [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	0.9	0.5
Restricted Stock, Performance-Based [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 0.6	$ 0.2