Consolidated Condensed Statements of Shareholders' Equity Statement - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Stock Employee Compensation Trust (SECT)	Supplemental Retirement Plan (SERP) Trust	Accumulated Other Comprehensive Loss	Class A Common Stock	Class A Common Stock Treasury Stock	Class A Common Stock Stock Employee Compensation Trust (SECT)	Class B Common Stock	Class B Common Stock Treasury Stock	Class B Common Stock Stock Employee Compensation Trust (SECT)	Class B Common Stock Supplemental Retirement Plan (SERP) Trust
Beginning of period at Oct. 01, 2022		$ 51,280	$ 516,123	$ 2,360,055	$ (1,047,012)	$ (73,602)	$ (58,989)	$ (311,042)
Increase (Decrease) in Stockholders' Equity
Issuance of shares			2,228		1,724
Equity-based compensation expense			2,443
Adjustments to market - SECT and SERP			29,717
Net earnings	$ 46,016			46,016
Dividends				(8,257)
Class A and B shares purchased					(10,447)
Issuance of shares - SECT						2,561
Purchase of shares - SECT	(1,753)					(1,753)
Adjustment to market						(16,895)	(12,822)
Other comprehensive income (loss)	53,853							53,853
End of period at Dec. 31, 2022	$ 1,525,181	51,280	550,511	2,397,814	(1,055,735)	(89,689)	(71,811)	(257,189)
Beginning of period - Common Stock at Oct. 01, 2022									43,806,835			7,472,878
Increase (Decrease) in Stockholders' Equity
Conversion of Class B to Class A									0			0
End of period - Common Stock at Dec. 31, 2022									43,806,835			7,472,878
Beginning of period, Shares at Oct. 01, 2022										(14,614,444)	(425,148)		(3,020,291)	(611,942)	(826,170)
Increase (Decrease) in Stockholders' Equity
Class A and B shares issued related to equity compensation, shares										35,550			72,740
Class A and B shares purchased, shares										(87,614)			(44,350)
Issuance of shares - SECT														30,069
Purchase of shares - SECT														(20,727)
End of period, Shares at Dec. 31, 2022										(14,666,508)	(425,148)		(2,991,901)	(602,600)	(826,170)
Increase (Decrease) in Stockholders' Equity
Common Stock, Dividends, Per Share, Declared	$ 0.26
Beginning of period at Sep. 30, 2023	$ 1,636,087	51,280	608,270	2,496,979	(1,057,938)	(114,769)	(93,126)	(254,609)
Increase (Decrease) in Stockholders' Equity
Issuance of shares			2,160		995
Equity-based compensation expense			3,454
Adjustments to market - SECT and SERP			59,377
Net earnings	47,812			47,812
Dividends				(8,619)
Class A and B shares purchased					(8,711)
Issuance of shares - SECT						5,001
Purchase of shares - SECT	(4,561)					(3,971)
Adjustment to market						(32,634)	(26,743)
Other comprehensive income (loss)	33,009							33,009
End of period at Dec. 30, 2023	$ 1,707,217	$ 51,280	$ 673,261	$ 2,536,172	$ (1,065,654)	$ (146,373)	$ (119,869)	$ (221,600)
Beginning of period - Common Stock at Sep. 30, 2023									43,822,344			7,457,369
Increase (Decrease) in Stockholders' Equity
Conversion of Class B to Class A									3,573			(3,573)
End of period - Common Stock at Dec. 30, 2023									43,825,917			7,453,796
Beginning of period, Shares at Sep. 30, 2023										(14,657,897)	(425,148)		(2,896,845)	(592,128)	(826,170)
Increase (Decrease) in Stockholders' Equity
Class A and B shares issued related to equity compensation, shares										18,411			64,263
Class A and B shares purchased, shares										(7,533)			(59,112)
Issuance of shares - SECT														37,308
Purchase of shares - SECT														(29,780)
End of period, Shares at Dec. 30, 2023										(14,647,019)	(425,148)		(2,891,694)	(584,600)	(826,170)
Increase (Decrease) in Stockholders' Equity
Common Stock, Dividends, Per Share, Declared	$ 0.27