Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Supplemental Employee Retirement Plan [Member] Common Stock [Member]	Supplemental Employee Retirement Plan [Member] Additional Paid-in Capital [Member]	Supplemental Employee Retirement Plan [Member] Retained Earnings [Member]	Supplemental Employee Retirement Plan [Member] AOCI Attributable to Parent [Member]	Supplemental Employee Retirement Plan [Member]	Pension Plan [Member] Common Stock [Member]	Pension Plan [Member] Additional Paid-in Capital [Member]	Pension Plan [Member] Retained Earnings [Member]	Pension Plan [Member] AOCI Attributable to Parent [Member]	Pension Plan [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Nov. 26, 2016											10,722,947
Balance at Nov. 26, 2016											$ 53,615	$ 255	$ 129,388	$ (2,553)	$ 180,705
Net income (loss)											0	0	18,256	0	18,256
Prior service cost of LTCA, net of tax											0	0	0	(528)
Actuarial adjustment to retirement plan, net of tax	$ 0	$ 0	$ 0	$ 511	$ 511
Regular dividends											0	0	(4,508)	0	(4,508)
Special dividends											$ 0	0	(3,758)	0	(3,758)
Issuance of common stock (in shares)											39,313
Issuance of common stock											$ 197	281	0	0	478
Purchase and retirement of common stock (in shares)											(24,310)
Purchase and retirement of common stock											$ (122)	(602)	0	0	(724)
Stock-based compensation											$ 0	1,028	0	0	1,028
Balance (in shares) at Nov. 25, 2017											10,737,950
Balance at Nov. 25, 2017											$ 53,690	962	139,378	(2,570)	191,460
Net income (loss)											0	0	8,218	0	8,218
Prior service cost of LTCA, net of tax											0	0	0	94	94
Actuarial adjustment to retirement plan, net of tax	0	0	0	683	683
Regular dividends											$ 0	0	(5,041)	0	(5,041)
Issuance of common stock (in shares)											63,403
Purchase and retirement of common stock (in shares)											(273,717)
Purchase and retirement of common stock											$ (1,369)	(2,160)	(3,091)	0	(6,620)
Stock-based compensation											0	1,133	0	0	1,133
Reclassification of certain tax effects											0	0	545	(545)
Issuance of common stock											$ 317	65	0	0	$ 382
Balance (in shares) at Nov. 24, 2018											10,527,636				10,527,636
Balance at Nov. 24, 2018											$ 52,638	0	140,009	(2,338)	$ 190,309
Net income (loss)											0	0	(1,928)	0	(1,928)
Prior service cost of LTCA, net of tax											0	0	0	94	94
Actuarial adjustment to retirement plan, net of tax	$ 0	$ 0	$ 0	$ 1,113	$ 1,113	$ 0	$ 0	$ 0	$ (105)	$ (105)
Regular dividends											$ 0	0	(5,133)	0	(5,133)
Issuance of common stock (in shares)											102,303
Purchase and retirement of common stock (in shares)											(513,649)
Purchase and retirement of common stock											$ (2,568)	(980)	(3,797)	0	(7,345)
Stock-based compensation											0	958	0	0	958
Issuance of common stock											511	217	0	0	728
Cumulative effect of a change in accounting principle											$ 0	0	(21)	0	$ (21)
Balance (in shares) at Nov. 30, 2019											10,116,290				10,116,290
Balance at Nov. 30, 2019											$ 50,581	$ 195	$ 129,130	$ (1,236)	$ 178,670