This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Restructuring and Other Charges - Summary of Restructuring and Other Activities by Major Type of Costs (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Oct. 01, 2021	Oct. 02, 2020
Restructuring Cost and Reserve [Line Items]
Impairment of real estate		$ 71,000	$ 2,400	$ 161,400
Gain on termination of lease		8,700
Impairment of equity method investment				(162,000)
AWE ML
Restructuring Cost and Reserve [Line Items]
Gain on termination of lease		8,700
Impairment of equity method investment			(38,500)
CH2M HILL Companies, Ltd.
Restructuring Cost and Reserve [Line Items]
Restructuring costs		161,063	99,590	324,183
Impairment of real estate	$ 78,300		2,400	161,400
Gain on termination of lease		(8,700)
Impairment of equity method investment		(91,300)
CH2M HILL Companies, Ltd. \| Lease Abandonments and Impairments
Restructuring Cost and Reserve [Line Items]
Restructuring costs		69,802	4,282	151,150
CH2M HILL Companies, Ltd. \| Voluntary and Involuntary Terminations
Restructuring Cost and Reserve [Line Items]
Restructuring costs		5,635	15,773	53,484
CH2M HILL Companies, Ltd. \| Outside Services
Restructuring Cost and Reserve [Line Items]
Restructuring costs		22,340	35,210	88,476
CH2M HILL Companies, Ltd. \| Other
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 63,286	$ 44,325	$ 31,073