Sale of Energy, Chemicals and Resources ("ECR") Business - Income Statement Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jan. 01, 2021	Dec. 27, 2019	Mar. 27, 2020	Oct. 02, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Earnings of the Group from Discontinued Operations	$ (14)	$ 77,587
Worley \| Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	0	7,099
Direct cost of contracts	0	(4,692)
Gross profit	0	2,407
Selling, general and administrative expenses	(19)	47,159
Operating (Loss) Profit	(19)	49,566
Gain on sale of ECR business		61,943	$ 935,100	$ 110,200
Other (expense) income, net	0
Other (expense) income, net		1
Earnings Before Taxes from Discontinued Operations	(19)	111,510
Income Tax Expense	5	(33,923)
Net Earnings of the Group from Discontinued Operations	$ (14)	$ 77,587

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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