Financial Instruments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	May 31, 2014	Nov. 30, 2013
Fair Value, Inputs, Level 1
Fair Value, Measurement Inputs, Disclosure [Line Items]
Money market funds	$ 62.7
Fair Value, Inputs, Level 2
Fair Value, Measurement Inputs, Disclosure [Line Items]
Long-term debt excluding credit facilities, fair value	297.9	293.0
Long-term debt excluding credit facilities, carrying amount	$ 274.2	$ 274.5