Investments in Associated Companies - Summarized Financial Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 25, 2022	Sep. 26, 2021	Sep. 27, 2020	Jun. 26, 2022	Mar. 27, 2022	Dec. 26, 2021
ASSETS
Current assets	$ 109,123	$ 108,799
Total assets	744,042	843,551
LIABILITIES AND MEMBERS' EQUITY
Current liabilities	131,136	141,624
Members' equity	15,005	41,097	$ (44,992)	$ 41,147	$ 39,481	$ 47,444
Total liabilities and members' equity	744,042	843,551	864,057	$ 794,836	$ 795,401	$ 831,849
Operating revenue	780,969	794,649	618,004
Operating expenses	761,775	744,505	571,129
Restructuring costs and other	22,720	7,182	13,751
Operating income	24,851	56,556	50,278
Net income	(2,017)	22,745	(1,975)
Less amortization of intangible assets	22,180	24,859	20,748
Equity in earnings	5,657	6,412	3,403
TNI Partners
LIABILITIES AND MEMBERS' EQUITY
Company's 50% share	4,354	4,731	3,714
Less amortization of intangible assets	0	0	209
Equity in earnings	4,354	4,731	3,505
MNI
LIABILITIES AND MEMBERS' EQUITY
Equity in earnings	1,303	1,681	(102)
TNI Partners
ASSETS
Current assets	2,801	2,238
Investments and other assets	1,584	1,693
Total assets	4,385	3,931
LIABILITIES AND MEMBERS' EQUITY
Current liabilities	5,005	5,027
Members' equity	(620)	(1,096)
Total liabilities and members' equity	4,385	3,931
Operating revenue	34,153	34,782	37,101
Operating expenses	25,445	25,320	29,673
Net income	8,708	9,462	7,428
MNI
ASSETS
Current assets	5,837	6,930
Investments and other assets	29,903	30,422
Total assets	35,740	37,352
LIABILITIES AND MEMBERS' EQUITY
Current liabilities	5,922	6,921
Other liabilities	5,696	6,470
Members' equity	24,122	23,961
Total liabilities and members' equity	35,740	37,352
Operating revenue	47,621	46,015	48,056
Operating expenses	37,922	35,583	46,845
Restructuring costs and other	169	107	274
Depreciation and amortization	672	711	697
Operating income	8,857	9,614	240
Net income	$ 2,605	$ 3,362	$ (204)