For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Revenue Accounting for Contracts (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Oct. 02, 2020	Jun. 26, 2020	Mar. 27, 2020	Dec. 27, 2019	Sep. 27, 2019	Jun. 28, 2019	Mar. 29, 2019	Dec. 28, 2018	Oct. 02, 2020	Sep. 27, 2019	Sep. 28, 2018
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	$ 3,519,689	$ 3,260,057	$ 3,427,180	$ 3,360,049	$ 3,392,862	$ 3,169,622	$ 3,091,596	$ 3,083,788	$ 13,566,975	$ 12,737,868	$ 10,579,773
Contract liability									$ 410,000	$ 350,300
U.S. Federal Government and it's Agencies \| Customer Concentration Risk
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Concentration risk, percentage									33.00%	27.00%	32.00%
United States
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									$ 10,158,508	$ 9,006,730	$ 6,908,988
Europe
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									2,253,284	2,242,976	2,495,805
Canada
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									227,067	213,172	189,865
Asia
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									117,698	195,023	163,761
India
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									50,618	62,543	52,533
Australia and New Zealand
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									537,076	533,251	578,108
South America and Mexico
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									11	7,416	17,656
Middle East and Africa
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues									$ 222,713	$ 476,757	$ 173,057