Revenue Recognition - Summary of Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 27, 2020	Sep. 27, 2019
Revenue from Contract with Customer [Abstract]
Accounts Receivable, Net, Current	$ 247,043	$ 189,115
Contract assets	223,739	195,651
Contract liabilities	19,745	19,991
Non-current contract liabilities	25,074	$ 24,404
Change ($)
Accounts receivable, net	57,928
Contract assets	28,088
Contract liabilities - current	(246)
Contract liabilities - non-current	$ 670
Change (%)
Accounts receivable, net	31.00%
Contract assets	14.00%
Contract liabilities - current	(1.00%)
Contract liabilities - non-current	3.00%

Accounts Receivable, Net, Percent, Increase (Decrease)

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Change In Contract With Customer, Assets And Liabilities Percent [Abstract]

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Contract With Customer, Asset, Increase (Decrease)

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Contract With Customer, Asset, Percent, Increase (Decrease)

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Contract With Customer, Liability, Increase (Decrease), Current

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Contract With Customer, Liability, Increase (Decrease), Noncurrent

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Contract With Customer, Liability, Percent, Increase (Decrease), Current

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Contract With Customer, Liability, Percent, Increase (Decrease), Noncurrent

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Increase (Decrease) In Accounts Receivable, Net

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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