Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands			12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2016	Feb. 28, 2018
Fiscal Year
Length of fiscal year			12 months	12 months	12 months
Cash and Cash Equivalents
Money market funds invested in U.S. Treasury obligations			$ 4,980	$ 29,432
Impairment of Investments in Long Lived Assets
Impairment losses			0	0	$ 0
Income Taxes
Accrual for uncertain income tax positions			$ 0
Recent Adopted Accounting Pronouncements
Corporate statutory income tax rate	21.00%	35.00%	22.00%
Reclassification resulted in a decrease to AOCI and an increase to retained earnings			$ 36
Deferred Tax Assets
Deferred tax asset			$ 480	$ 970
ASU 2016-09
Deferred Tax Assets
Deferred tax asset						$ 879
ASU 2016-09 | Forecast Adjustment
Deferred Tax Assets
Deferred tax asset						$ 879