Reportable Segments - Segment Reporting Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 18, 2020	Mar. 11, 2020	Mar. 11, 2020
Sales:
Total Sales	$ 41,947	$ 68,561	$ 163,710
Segment level profit:
Total	5,086	6,723	16,499
Depreciation and amortization:
Depreciation and amortization	2,142	2,677	6,440
Capital expenditures:
Total	433	545	1,490
Loss before income taxes and discontinued operations:
Segment level profit	5,086	6,723	16,499
Opening costs	0	(2)	(14)
Depreciation and amortization	(2,142)	(2,677)	(6,440)
Selling, general and administrative expenses	(4,267)	(6,816)	(16,974)
Other charges	(416)	(1,509)	(2,748)
Net provision (gain) for asset impairments and restaurant closings	85	(661)	(1,770)
Net loss (gain) on disposition of property and equipment	(117)	2,527	2,498
Interest income	8	5	28
Interest expense	(1,212)	(1,473)	(3,435)
Other income, net	30	148	388
Loss before income taxes and discontinued operations	(2,945)	(3,735)	(11,968)
Luby's cafeterias
Sales:
Total Sales	31,949	47,886	115,030
Segment level profit:
Total	4,896	4,877	12,786
Loss before income taxes and discontinued operations:
Segment level profit	4,896	4,877	12,786
Fuddruckers restaurants
Sales:
Total Sales	4,550	11,872	27,551
Segment level profit:
Total	(412)	527	494
Loss before income taxes and discontinued operations:
Segment level profit	(412)	527	494
Cheeseburger in Paradise restaurants
Sales:
Total Sales	0	647	1,492
Segment level profit:
Total	(85)	(28)	(95)
Loss before income taxes and discontinued operations:
Segment level profit	(85)	(28)	(95)
Culinary contract services
Sales:
Total Sales	4,918	6,998	16,772
Segment level profit:
Total	451	598	1,424
Loss before income taxes and discontinued operations:
Segment level profit	451	598	1,424
Fuddruckers franchise operations
Sales:
Total Sales	530	1,158	2,865
Segment level profit:
Total	236	749	1,890
Loss before income taxes and discontinued operations:
Segment level profit	236	749	1,890
Operating Segments | Luby's cafeterias
Depreciation and amortization:
Depreciation and amortization	1,530	1,738	4,182
Capital expenditures:
Total	416	414	1,238
Loss before income taxes and discontinued operations:
Depreciation and amortization	(1,530)	(1,738)	(4,182)
Operating Segments | Fuddruckers restaurants
Depreciation and amortization:
Depreciation and amortization	167	387	937
Capital expenditures:
Total	17	90	139
Loss before income taxes and discontinued operations:
Depreciation and amortization	(167)	(387)	(937)
Operating Segments | Cheeseburger in Paradise restaurants
Depreciation and amortization:
Depreciation and amortization	0	19	47
Capital expenditures:
Total	0	0	2
Loss before income taxes and discontinued operations:
Depreciation and amortization	0	(19)	(47)
Operating Segments | Culinary contract services
Depreciation and amortization:
Depreciation and amortization	8	5	17
Loss before income taxes and discontinued operations:
Depreciation and amortization	(8)	(5)	(17)
Operating Segments | Fuddruckers franchise operations
Depreciation and amortization:
Depreciation and amortization	1	178	414
Capital expenditures:
Total	0	0	14
Loss before income taxes and discontinued operations:
Depreciation and amortization	(1)	(178)	(414)
Corporate
Depreciation and amortization:
Depreciation and amortization	436	350	843
Capital expenditures:
Total	0	41	97
Loss before income taxes and discontinued operations:
Depreciation and amortization	$ (436)	$ (350)	$ (843)