Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	Feb. 28, 2017	Nov. 30, 2016
Fair Value, Inputs, Level 1
Fair Value, Measurement Inputs, Disclosure [Line Items]
Money market funds	$ 138.5
Fair Value, Inputs, Level 2
Fair Value, Measurement Inputs, Disclosure [Line Items]
Long-term debt excluding credit facilities, fair value	274.1	$ 278.2
Long-term debt excluding credit facilities, carrying amount	$ 264.8	$ 265.0