Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Nov. 30, 2017	Nov. 30, 2016	Nov. 30, 2015
Accounting Policies [Abstract]
Cash equivalents	$ 481,100	$ 396,100
Schedule of Equity Method Investments [Line Items]
Impairment of Real Estate	20,605	49,580	$ 8,030
Property and equipment amount	19,521	14,240
Accumulated depreciation	19,000	18,200
Depreciation expense	2,791	3,637	3,411
Advertising costs incurred	34,400	32,700	33,400
Expensed legal fees	$ 14,000	$ 13,600	$ 11,700
Minimum
Schedule of Equity Method Investments [Line Items]
Estimated useful life for depreciation of property and equipment	2 years
Maximum
Schedule of Equity Method Investments [Line Items]
Estimated useful life for depreciation of property and equipment	10 years