Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 27, 2025	Jun. 28, 2025	Mar. 29, 2025	Dec. 28, 2024	Sep. 28, 2024	Jun. 29, 2024	Mar. 30, 2024	Dec. 30, 2023	Sep. 30, 2023	Oct. 01, 2022
Current assets
Cash and cash equivalents	$ 62,013	$ 58,191	$ 62,124	$ 73,448	$ 61,694	$ 50,572	$ 59,066	$ 126,398	$ 68,959
Restricted cash	200	823	602	360	123	946	665	430	185
Receivables, net	506,768	529,753	537,179	472,310	419,971	452,967	419,399	381,609	447,423
Unbilled receivables	744,352	719,002	719,569	722,384	690,572	745,680	773,379	743,497	634,787
Inventories, net	914,302	924,682	901,221	884,828	862,541	828,518	807,852	783,668	718,489
Prepaid expenses and other current assets	142,345	153,479	95,554	77,783	87,745	72,596	75,911	59,577	64,262
Total current assets	2,369,980	2,385,930	2,316,249	2,231,113	2,122,646	2,151,279	2,136,272	2,095,179	1,934,105
Property, plant and equipment, net	1,019,906	988,125	960,015	934,087	928,588	904,710	886,045	856,462	826,260
Operating lease right-of-use assets	52,799	52,877	55,354	56,744	52,591	57,669	57,074	59,489	56,067
Goodwill	842,313	802,089	825,415	818,503	833,764	827,319	828,469	833,413	821,301	$ 805,320
Intangible assets, net	66,101	57,182	57,915	59,469	63,479	66,422	68,876	72,663	71,637
Deferred income taxes	22,459	41,121	34,961	27,690	23,884	24,101	15,556	9,250	8,723
Other assets	52,497	56,696	57,146	54,242	52,695	48,887	49,390	53,809	50,254
Total assets	4,426,055	4,384,020	4,307,055	4,181,848	4,077,647	4,080,387	4,041,682	3,980,265	3,768,347
Current liabilities
Current installments of long-term debt	1,563				0
Accounts payable	318,402	289,160	293,952	267,954	293,888	267,194	268,631	262,055	265,473
Accrued compensation	106,040	98,292	69,411	68,366	104,027	101,531	76,161	65,949	112,654
Contract advances and progress billings	372,988	301,270	307,640	293,160	302,126	353,736	405,230	446,547	337,707
Accrued liabilities and other	320,075	318,043	297,637	301,463	313,373	290,824	281,741	253,143	241,813
Total current liabilities	1,119,068	1,006,765	968,640	930,943	1,013,414	1,013,285	1,031,763	1,027,694	957,647
Long-term debt, excluding current installments	944,123	1,081,674	1,165,662	1,104,151	874,139	958,127	948,615	920,103	863,092
Long-term pension and retirement obligations	157,218	177,688	172,395	162,222	167,161	160,635	160,265	160,825	157,455
Deferred income taxes	32,600	27,614	26,336	26,036	27,652	24,619	24,546	32,086	33,475
Other long-term liabilities	180,491	177,233	167,982	171,962	166,464	162,162	158,213	161,816	154,921
Total liabilities	2,433,500	2,470,974	2,501,015	2,395,314	2,248,830	2,318,828	2,323,402	2,302,524	2,166,590
Shareholders’ equity
Additional paid-in capital	839,328	769,935	750,119	777,060	784,509	726,656	702,272	673,261	608,270
Retained earnings	2,834,548	2,779,325	2,729,980	2,684,515	2,635,950	2,602,371	2,552,209	2,506,656	2,462,640
Treasury shares	(1,209,200)	(1,205,305)	(1,204,032)	(1,141,242)	(1,082,240)	(1,073,027)	(1,071,558)	(1,065,654)	(1,057,938)
Stock Employee Compensation Trust	(195,491)	(173,214)	(162,945)	(186,219)	(194,049)	(167,757)	(153,295)	(146,373)	(114,769)
Supplemental Retirement Plan Trust	(170,191)	(147,042)	(141,490)	(156,865)	(163,821)	(140,449)	(129,709)	(119,869)	(93,126)
Accumulated other comprehensive loss	(157,719)	(161,933)	(216,872)	(241,995)	(202,812)	(237,515)	(232,919)	(221,560)	(254,600)
Total shareholders’ equity	1,992,555	1,913,046	1,806,040	1,786,534	1,828,817	1,761,559	1,718,280	1,677,741	1,601,757
Total liabilities and shareholders’ equity	4,426,055	4,384,020	4,307,055	4,181,848	4,077,647	4,080,387	4,041,682	3,980,265	3,768,347
Class A Common Stock
Shareholders’ equity
Common stock	43,864	43,864	43,852	43,844	43,835	43,835	43,826	43,826	43,822
Class B Common Stock
Shareholders’ equity
Common stock	$ 7,416	$ 7,416	$ 7,428	$ 7,436	$ 7,445	$ 7,445	$ 7,454	$ 7,454	$ 7,458