Sale of Energy, Chemicals and Resources ("ECR") Business (Details) - USD ($) $ in Thousands		12 Months Ended
Apr. 26, 2019	Oct. 01, 2021	Oct. 02, 2020	Sep. 27, 2019
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Other expense				$ (14,800)
Net Earnings of the Group from Discontinued Operations		$ 10,008	$ 137,984	559,214
ECR Business \| Discontinued Operations
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Revenues	$ 95,300	0	11,235	2,725,699
Direct cost of contracts		0	(6,152)	(2,338,113)
Gross profit		0	5,083	387,586
Selling, general and administrative expenses		(2,784)	32,668	(320,264)
Operating Profit (Loss)		(2,784)	37,751	67,322
Gain on sale of businesses	$ (1,100,000)	(15,608)	(110,236)	(935,110)
Other income		447	515
Other expense				(47,390)
Earnings Before Taxes from Discontinued Operations		13,271	148,502	955,042
Income Tax Expense		(3,263)	(10,518)	(395,828)
Net Earnings of the Group from Discontinued Operations		$ 10,008	$ 137,984	$ 559,214

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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