Sale of Energy, Chemicals and Resources ("ECR") Business - Income Statement Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Mar. 27, 2020	Mar. 29, 2019	Mar. 27, 2020	Mar. 29, 2019	Sep. 27, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other (expense) income, net		$ (6,400)		$ (12,800)
Net Earnings (Loss) of the Group from Discontinued Operations	$ 29,880	(57,006)	$ 107,468	3,153
Worley \| Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	4,063	1,161,083	11,162	2,325,790
Direct cost of contracts	(1,363)	(999,944)	(6,055)	(1,995,550)
Gross profit	2,700	161,139	5,107	330,240
Selling, general and administrative expenses	(2,999)	(202,590)	44,161	(293,600)
Operating (Loss) Profit	(299)	(41,451)	49,268	36,640
Gain on sale of ECR business	19,967	0	81,910	0	$ 935,100
Other (expense) income, net	(1,361)	(34,413)	(1,361)	(32,293)
Earnings (Loss) Before Taxes from Discontinued Operations	18,307	(75,864)	129,817	4,347
Income Tax Benefit (Expense)	11,573	18,858	(22,349)	(1,194)
Net Earnings (Loss) of the Group from Discontinued Operations	$ 29,880	$ (57,006)	$ 107,468	$ 3,153

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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