Cash, Cash Equivalents and Investments (Fair Value of Debt Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Aug. 31, 2015	Nov. 30, 2014
Investments and Cash [Abstract]
Due in one year or less	$ 13,093	$ 11,140
Due after one year	16,098	9,046
Total	$ 29,191	$ 20,186