Sale of Energy, Chemicals and Resources ("ECR") Business - Income Statement Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Jul. 02, 2021	Apr. 02, 2021	Jun. 26, 2020	Jul. 02, 2021	Jun. 26, 2020	Oct. 02, 2020	Sep. 27, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Earnings of the Group from Discontinued Operations	$ 384		$ 18,043	$ 11,690	$ 125,511
Worley \| Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	0		59	0	11,221
Direct cost of contracts	0		(69)	0	(6,124)
Gross profit	0		(10)	0	5,097
Selling, general and administrative expenses	0		(801)	(34)	43,359
Operating (Loss) Profit	0		(811)	(34)	48,456
Gain on sale of ECR business	0	$ 15,600	31,456	15,608	113,366	$ 110,200	$ 935,100
Other expense, net	509		1,472	(72)	112
Earnings Before Taxes from Discontinued Operations	509		32,117	15,502	161,934
Income Tax (Expense) Benefit	(125)		(14,074)	(3,812)	(36,423)
Net Earnings of the Group from Discontinued Operations	$ 384		$ 18,043	$ 11,690	$ 125,511

Disposal Group, Including Discontinued Operation, Other Expense, Net

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