Revenue and Contract Balances - Summary of Contract Liabilities/Assets (Details) - USD ($) $ in Thousands	Mar. 29, 2020	Sep. 29, 2019
Revenue from Contract with Customer [Abstract]
Contract assets	$ 109,166	$ 114,324
Contract liabilities	(189,741)	(165,611)
Net contract liabilities	(80,575)	(51,287)
Disaggregation of Revenue [Line Items]
Contract assets	109,166	114,324
Contract Retentions
Revenue from Contract with Customer [Abstract]
Contract assets	25,500	26,500
Disaggregation of Revenue [Line Items]
Contract assets	$ 25,500	$ 26,500