Revenue (Significant Changes in Contact Assets and Liabilities) (Details) $ in Thousands	6 Months Ended
Mar. 30, 2019 USD ($)
Change in Contract with Customer, Asset [Abstract]
Balance, September 29, 2018	$ 70,474
Cumulative transition adjustment upon adoption	(8,002)
Changes in estimated stage of completion	69,857
Transfers to accounts receivable, net	(62,265)
Acquisitions	1,518
Other	(407)
Balance, March 30, 2019	71,175
Change in Contract with Customer, Liability [Abstract]
Balance, September 29, 2018	80,131
Cumulative transition adjustment upon adoption	20,557
Revenue recognized included in balance at beginning of period	(58,947)
Increases due to payments received, excluding amounts recognized as revenue during period	64,121
Acquisitions	4,777
Other	(876)
Balance, March 30, 2019	$ 109,763

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Amount of increase (decrease) in Contract with Customer, Liability, due to payments received, excluding amounts recognized as revenue during the period

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Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) 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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