Financial Instruments Financial Instruments (Details 3) - USD ($) $ in Thousands	Mar. 02, 2019	Dec. 01, 2018	Mar. 03, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$ 2,015		$ 2,901
Commercial paper	300		400
Total cash equivalents	2,315		3,301
Municipal and corporate bonds	402		423
Municipal and corporate bonds		$ 12,030	8,630
Total assets at fair value		14,747	12,354
Quoted Prices in Active Markets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	2,015		2,901
Commercial paper	0		0
Total cash equivalents	2,015		2,901
Municipal and corporate bonds	0		0
Municipal and corporate bonds		0	0
Total assets at fair value		2,015	2,901
Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	0		0
Commercial paper	300		400
Total cash equivalents	300		400
Municipal and corporate bonds	$ 402		423
Municipal and corporate bonds		12,030	8,630
Total assets at fair value		$ 12,732	$ 9,453