Acquisition	12 Months Ended
	Oct. 03, 2020
Acquisition [Abstract]
Acquisition	AcquisitionOn July 27, 2018, the Company purchased the assets of one of the business lines of Cascade Controls, Inc. ("Cascade"), a new product introduction company in Portland, Oregon, for $12.4 million in cash, subject to certain customary post-closing adjustments. In the three months ended December 29, 2018, the Company received a $1.2 million purchase price adjustment as a result of a post-closing adjustment. Plexus acquired substantially all of the inventory, equipment and other assets of the business line, hired a majority of its employees and sub-leased one of Cascade's facilities. This transaction has been accounted for as a business combination.The acquisition resulted in a $12.4 million cash outflow in fiscal 2018 and a $1.2 million cash inflow in fiscal 2019 included in "Business acquisition" in the accompanying Consolidated Statements of Cash Flows. Additionally, $5.7 million, $6.9 million $8.2 million of intangible assets related to customer relationships is included in non-current "Other" assets in the accompanying Consolidated Balance Sheet for fiscal 2020, 2019 and 2018, respectively. The intangible assets are amortized on a straight-line basis and result in amortization expense of approximately $1.2 million per year. There were no other material impacts to the Company's Consolidated Financial Statements as a result of the acquisition.