Accumulated Other Comprehensive Loss (Details) $ in Thousands	9 Months Ended
	Aug. 31, 2017 USD ($)
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 1, 2016	$ (28,425)
Other comprehensive loss before reclassifications, net of tax	11,291
Balance, August 31, 2017	(17,134)
Unrealized Gains (Losses) on Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 1, 2016	(136)
Other comprehensive loss before reclassifications, net of tax	105
Balance, August 31, 2017	(31)
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 1, 2016	(28,561)
Other comprehensive loss before reclassifications, net of tax	11,396
Balance, August 31, 2017	$ (17,165)