Plexus (PLXS) 10-K 17 Nov 17 2017 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Billions	12 Months Ended
	Sep. 30, 2017	Nov. 13, 2017	Apr. 01, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Entity Registrant Name	PLEXUS CORP
Entity Central Index Key	785,786
Current Fiscal Year End Date	--09-30
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		33,585,056
Entity Current Reporting Status	Yes
Entity Public Float			$ 1.9
Entity Well-Known Season Issuer	Yes
Entity Voluntary Filers	No

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Income Statement [Abstract]
Net sales	$ 2,528,052,000	$ 2,556,004,000	$ 2,654,290,000
Cost of sales	2,272,197,000	2,328,645,000	2,414,740,000
Gross profit	255,855,000	227,359,000	239,550,000
Selling and administrative expenses	125,947,000	120,886,000	122,423,000
Restructuring and other charges	0	7,034,000	1,691,000
Operating income	129,908,000	99,439,000	115,436,000
Other income (expense):
Interest expense	(13,578,000)	(14,635,000)	(13,964,000)
Interest income	5,042,000	4,242,000	3,499,000
Miscellaneous	451,000	(1,652,000)	1,324,000
Income before income taxes	121,823,000	87,394,000	106,295,000
Income tax expense	9,761,000	10,967,000	11,963,000
Net income	$ 112,062,000	$ 76,427,000	$ 94,332,000
Earnings per share:
Basic (in dollars per share)	$ 3.33	$ 2.29	$ 2.81
Diluted (in dollars per share)	$ 3.24	$ 2.24	$ 2.74
Weighted average shares outstanding:
Basic (in shares)	33,612	33,374	33,618
Diluted (in shares)	34,553	34,098	34,379
Other comprehensive income (loss):
Derivative instrument fair value adjustment	$ 2,405,000	$ 8,967,000	$ (11,223,000)
Foreign currency translation adjustments	4,155,000	(14,035,000)	(13,830,000)
Other comprehensive income (loss)	6,560,000	(5,068,000)	(25,053,000)
Total comprehensive income	$ 118,622,000	$ 71,359,000	$ 69,279,000

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Current assets:
Cash and cash equivalents	$ 568,860	$ 432,964
Restricted cash	394	0
Accounts receivable, net of allowances of $980 and $2,368, respectively	365,513	416,888
Inventories	654,642	564,131
Prepaid expenses and other	28,046	19,364
Total current assets	1,617,455	1,433,347
Property, plant and equipment, net	314,665	291,225
Deferred income taxes	5,292	4,834
Other	38,770	36,413
Total non-current assets	358,727	332,472
Total assets	1,976,182	1,765,819
Current liabilities:
Current portion of long-term debt and capital lease obligations	286,934	78,507
Accounts payable	413,999	397,200
Customer deposits	107,837	84,637
Accrued salaries and wages	49,376	41,806
Other accrued liabilities	49,445	48,286
Total current liabilities	907,591	650,436
Long-term debt and capital lease obligations, net of current portion	26,173	184,002
Other liabilities	16,479	14,584
Total non-current liabilities	42,652	198,586
Total liabilities	950,243	849,022
Commitments and contingencies
Shareholders’ equity:
Preferred stock, $.01 par value, 5,000 shares authorized, none issued or outstanding	0	0
Common stock, $.01 par value, 200,000 shares authorized, 51,934 and 51,272 shares issued, respectively, and 33,464 and 33,457 shares outstanding, respectively	519	513
Additional paid-in capital	555,297	530,647
Common stock held in treasury, at cost, 18,470 and 17,815 shares, respectively	(574,104)	(539,968)
Retained earnings	1,049,206	937,144
Accumulated other comprehensive loss	(4,979)	(11,539)
Total shareholders’ equity	1,025,939	916,797
Total liabilities and shareholders’ equity	$ 1,976,182	$ 1,765,819

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowances	$ 980	$ 2,368
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	51,934,000	51,272,000
Common stock, shares outstanding (in shares)	33,464,000	33,457,000
Treasury stock, shares (in shares)	18,470,000	17,815,000

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Sep. 27, 2014		33,653
Beginning balance at Sep. 27, 2014	$ 781,133	$ 500	$ 475,634	$ (479,968)	$ 766,385	$ 18,582
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	94,332				94,332
Other comprehensive income (loss)	(25,053)					(25,053)
Treasury shares purchased (in shares)		(745)
Treasury shares purchased	(30,000)			(30,000)
Share-based compensation expense	13,252		13,252
Exercise of stock options, including tax benefits (in shares)		592
Exercise of stock options, including tax benefits	8,608	$ 6	8,602
Ending balance (in shares) at Oct. 03, 2015		33,500
Ending balance at Oct. 03, 2015	842,272	$ 506	497,488	(509,968)	860,717	(6,471)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	76,427				76,427
Other comprehensive income (loss)	(5,068)					(5,068)
Treasury shares purchased (in shares)		(761)
Treasury shares purchased	(30,000)			(30,000)
Share-based compensation expense	19,341		19,341
Exercise of stock options, including tax benefits (in shares)		718
Exercise of stock options, including tax benefits	$ 13,825	$ 7	13,818
Ending balance (in shares) at Oct. 01, 2016	33,457	33,457
Ending balance at Oct. 01, 2016	$ 916,797	$ 513	530,647	(539,968)	937,144	(11,539)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	112,062				112,062
Other comprehensive income (loss)	6,560					6,560
Treasury shares purchased (in shares)		(655)
Treasury shares purchased	(34,136)			(34,136)
Share-based compensation expense	17,411		17,411
Exercise of stock options, including tax benefits (in shares)		662
Exercise of stock options, including tax benefits	$ 7,245	$ 6	7,239
Ending balance (in shares) at Sep. 30, 2017	33,464	33,464
Ending balance at Sep. 30, 2017	$ 1,025,939	$ 519	$ 555,297	$ (574,104)	$ 1,049,206	$ (4,979)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Cash flows from operating activities
Net income	$ 112,062	$ 76,427	$ 94,332
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation	45,330	47,414	48,378
Amortization of deferred financing fees	311	405	304
(Gain) Loss on sale of property, plant and equipment, net	(162)	1,215	123
Deferred income taxes	(366)	(330)	(597)
Share-based compensation expense	17,411	19,341	13,252
Changes in operating assets and liabilities:
Accounts receivable	53,705	(36,990)	(64,876)
Inventories	(86,072)	(785)	(48,202)
Other current and noncurrent assets	(8,740)	2,913	6,398
Accounts payable	6,894	5,839	5,283
Customer deposits	22,599	4,466	25,843
Other current and noncurrent liabilities	8,762	7,823	(3,666)
Cash flows provided by operating activities	171,734	127,738	76,572
Cash flows from investing activities
Payments for property, plant and equipment	(38,538)	(31,123)	(35,076)
Proceeds from sales of property, plant and equipment	704	4,607	407
Cash flows used in investing activities	(37,834)	(26,516)	(34,669)
Cash flows from financing activities
Borrowings under credit facility and other short-term borrowings	331,076	625,000	483,000
Payments on debt and capital lease obligations	(302,880)	(629,571)	(487,811)
Debt issuance costs	0	(545)	0
Repurchases of common stock	(34,136)	(30,000)	(30,000)
Proceeds from exercise of stock options	13,368	16,407	11,380
Payments related to tax withholding for share-based compensation	(6,123)	(2,582)	(2,772)
Cash flows provided by (used in) financing activities	1,305	(21,291)	(26,203)
Effect of exchange rate changes on cash and cash equivalents	1,085	(4,073)	(5,185)
Net increase in cash and cash equivalents and restricted cash	136,290	75,858	10,515
Cash and cash equivalents and restricted cash:
Beginning of period	432,964	357,106	346,591
End of period	569,254	432,964	357,106
Supplemental disclosure information:
Interest paid	13,812	14,927	13,483
Income taxes paid	$ 10,158	$ 11,364	$ 11,157

Description of Business and Sig

Description of Business and Significant Accounting Policies	12 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Description of Business and Significant Accounting Policies	Description of Business and Significant Accounting Policies Description of Business: Plexus Corp. and its subsidiaries (together "Plexus" or the "Company,") participate in the Electronic Manufacturing Services ("EMS") industry. Plexus has been partnering with companies to transform concepts into branded products and deliver them to customers in the Healthcare/Life Sciences, Industrial/Commercial, Communications and Aerospace/Defense market sectors. Plexus is headquartered in Neenah, Wisconsin and has operations in the Americas ("AMER"), Europe, Middle East, and Africa ("EMEA") and Asia-Pacific ("APAC") regions. Significant Accounting Policies Consolidation Principles and Basis of Presentation: The consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") and include the accounts of Plexus Corp. and its subsidiaries. All intercompany transactions have been eliminated. Certain prior period amounts have been reclassified to conform to the current period presentation. The Company’s fiscal year ends on the Saturday closest to September 30. The Company also uses a "4-4-5" weekly accounting system for the interim periods in each quarter. Each quarter, therefore, ends on a Saturday at the end of the 4-4-5 period. Periodically, an additional week must be added to the fiscal year to re-align with the Saturday closest to September 30. Fiscal 2017 and fiscal 2016 each included 52 weeks; fiscal 2015 included 53 weeks. Cash and Cash Equivalents and Restricted Cash: Cash equivalents include short-term highly liquid investments and are classified as Level 1 in the fair value hierarchy described below. Restricted cash represents cash received from customers to settle invoices sold under accounts receivable purchase agreements that is contractually required to be set aside. The restrictions will lapse when the cash is remitted to the purchaser of the receivables. Restricted cash is also classified as Level 1 in the fair value hierarchy described below. As of September 30, 2017 and October 1, 2016 , cash and cash equivalents and restricted cash consisted of the following (in thousands): 2017 2016 Cash $ 264,222 $ 175,396 Money market funds and other 304,638 257,568 Restricted cash 394 — Total cash and cash equivalents and restricted cash $ 569,254 $ 432,964 Inventories: Inventories are valued at the lower of cost or market. Cost is determined by the first-in, first-out ("FIFO") method. Valuing inventories at the lower of cost or market requires the use of estimates and judgment. Customers may cancel their orders, change production quantities or delay production for a number of reasons that are beyond the Company’s control. Any of these, or certain additional actions, could impact the valuation of inventory. Any actions taken by the Company’s customers that could impact the value of its inventory are considered when determining the lower of cost or market valuations. In certain instances, in accordance with contractual terms, the Company receives customer deposits to offset obsolete and excess inventory risks. Property, Plant and Equipment and Depreciation: Property, plant and equipment is stated at cost and depreciated using the straight-line method over the estimated useful lives of the respective assets. Estimated useful lives for major classes of depreciable assets are as follows: Buildings and improvements 5-39 years Machinery and equipment 3-7 years Computer hardware and software 3-10 years Certain facilities and equipment held under capital leases are classified as property, plant and equipment and amortized using the straight-line method over the term of the lease and the related obligations are recorded as liabilities. Amortization of assets held under capital leases is included in depreciation expense (see Note 3, "Property, Plant and Equipment") and the financing component of the lease payments is classified as interest expense. Maintenance and repairs are expensed as incurred. The Company capitalizes significant costs incurred in the acquisition or development of software for internal use. This includes costs of the software, consulting services and compensation costs for employees directly involved in developing internal use computer software. Impairment of Long-Lived Assets: Long-lived assets, including property, plant and equipment and intangible assets with finite lives are reviewed for impairment and written down to fair value when facts and circumstances indicate that the carrying value of long-lived assets or asset groups may not be recoverable through estimated future undiscounted cash flows. If an impairment has occurred, a write-down to estimated fair value is made and the impairment loss is recognized as a charge against current operations. The impairment analysis is based on management’s assumptions, including future revenue and cash flow projections. Circumstances that may lead to impairment of property, plant and equipment and intangible assets with finite lives include reduced expectations for future performance or industry demand and possible further restructurings, among others. Revenue Recognition: Net sales from manufacturing services are recognized when the product has been shipped, the risk of ownership has transferred to the customer, the price to the buyer is fixed or determinable, and recoverability is reasonably assured. This point depends on contractual terms and generally occurs upon shipment of the goods from Plexus. Generally, there are no formal customer acceptance requirements or further obligations related to manufacturing services; if such requirements or obligations exist, then a sale is recognized at the time when such requirements are completed and such obligations are fulfilled. Net sales also include amounts billed to customers for shipping and handling. The corresponding shipping and handling costs are included in cost of sales. Net sales from engineering design and development services, which are generally performed under contracts with a duration of twelve months or less, are typically recognized as program costs are incurred by utilizing the proportional performance model. The completed performance model is used if certain customer acceptance criteria exist. Any losses are recognized when anticipated. Net sales from engineering design and development services were less than 5.0% of consolidated net sales for each of fiscal 2017 , 2016 and 2015 . Income Taxes: Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The Company does not currently provide for additional U.S. and foreign income taxes that would become payable upon the repatriation of undistributed earnings. The Company maintains valuation allowances when it is more likely than not that all or a portion of a deferred tax asset will not be realized. In determining whether a valuation allowance is required, the Company takes into account such factors as prior earnings history, expected future earnings, carryback and carryforward periods, and tax strategies that could potentially enhance the likelihood of the realization of a deferred tax asset. Foreign Currency Translation & Transactions: The Company translates assets and liabilities of subsidiaries operating outside of the U.S. with a functional currency other than the U.S. dollar into U.S. dollars using exchange rates in effect at the relevant balance sheet date and net sales, expenses and cash flows at the average exchange rates during the respective periods. Adjustments resulting from translation of the financial statements are recorded as a component of "Accumulated other comprehensive loss." Exchange gains and losses arising from transactions denominated in a currency other than the functional currency of the entity involved and remeasurement adjustments for foreign operations where the U.S. dollar is the functional currency are included in the Consolidated Statements of Comprehensive Income as a component of "Miscellaneous income (expense)." Exchange gains (losses) on foreign currency transactions were $2.3 million , $(1.7) million , and $1.3 million for fiscal 2017 , 2016 and 2015 , respectively. These amounts include the amount of gain (loss) recognized in income during each fiscal year due to forward currency exchange contracts entered into to hedge recognized assets or liabilities ("non-designated hedges") the Company entered into during each respective year. Refer to Note 5, "Derivatives and Fair Value Measurements," for further details on derivatives. Derivatives: All derivatives are recognized on the balance sheets at fair value. The Company periodically enters into forward currency exchange contracts and interest rate swaps. On the date a derivative contract is entered into, the Company designates the derivative as a non-designated hedge or a hedge of a forecasted transaction or of the variability of cash flows to be received or paid related to a recognized asset or liability (a "cash flow" hedge). The Company does not enter into derivatives for speculative purposes. Changes in the fair value of non-designated derivatives are recorded in earnings as are the gains or losses related to the hedged asset or liability. Changes in the fair value of a derivative that qualifies as a cash flow hedge are recorded in "Accumulated other comprehensive loss" within shareholders’ equity, until earnings are affected by the variability of cash flows. Certain forward currency exchange contracts are treated as cash flow hedges and, therefore, $2.4 million , $9.0 million and $(11.2) million was recorded in "Accumulated other comprehensive loss" for fiscal 2017 , 2016 and 2015 , respectively. See Note 5, "Derivatives and Fair Value Measurements," for further information. Grants from Government Authorities: Grants from governments are recognized at their fair value where there is reasonable assurance that the grant funds will be received and the Company will comply with all attached conditions to the grant. Government grants relating to property, plant and equipment are recorded as an offset to the carrying value of the related assets at the time of capitalization. Government grants relating to other costs incurred are recognized as an offset to those related costs, for which the grants are intended to compensate for, at the time they are recognized. Earnings Per Share: The computation of basic earnings per common share is based upon the weighted average number of common shares outstanding and net income. The computation of diluted earnings per common share reflects additional dilution from share-based awards, excluding any with an antidilutive effect. See Note 7, "Earnings Per Share," for further information. Share-based Compensation: The Company measures all grants of share-based payments to employees, including grants of employee stock options, at fair value and expenses them in the Consolidated Statements of Comprehensive Income over the service period (generally the vesting period) of the grant. See Note 9, "Benefit Plans," for further information. Comprehensive Income (Loss): The Company follows the established standards for reporting comprehensive income (loss), which is defined as the changes in equity of an enterprise except those resulting from shareholder transactions. Accumulated other comprehensive loss consists of the following as of September 30, 2017 and October 1, 2016 (in thousands): 2017 2016 Foreign currency translation adjustments $ (7,482 ) $ (11,637 ) Cumulative change in fair value of derivative instruments 2,503 98 Accumulated other comprehensive loss $ (4,979 ) $ (11,539 ) Refer to Note 5, "Derivatives and Fair Value Measurements," for further explanation regarding the change in fair value of derivative instruments that is recorded to "Accumulated other comprehensive loss." Use of Estimates: The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. Fair Value of Financial Instruments: The Company holds financial instruments consisting of cash and cash equivalents, restricted cash, accounts receivable, certain deferred compensation assets held under trust arrangements, accounts payable, debt, derivatives, and capital lease obligations. The carrying values of cash and cash equivalents, restricted cash, accounts receivable, accounts payable, and capital lease obligations as reported in the consolidated financial statements approximate fair value. Derivatives and certain deferred compensation assets held under trust arrangements are recorded at fair value. Accounts receivable are reflected at net realizable value based on anticipated losses due to potentially uncollectible balances. Anticipated losses are based on management’s analysis of historical losses and changes in customers’ credit status. The fair value of the Company’s debt was $284.5 million and $251.4 million as of September 30, 2017 and October 1, 2016 , respectively. The carrying value of the Company's debt was $283.0 million and $250.0 million as of September 30, 2017 and October 1, 2016 , respectively. The Company uses quoted market prices when available or discounted cash flows to calculate fair value. If measured at fair value in the financial statements, long-term debt (including the current portion) would be classified as Level 2 in the fair value hierarchy described below. The fair values of the Company’s derivatives are disclosed in Note 5, "Derivatives and Fair Value Measurements." The fair values of the deferred compensation assets held under trust arrangements are discussed in Note 9, "Benefit Plans." Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (or exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The accounting guidance establishes a fair value hierarchy based on three levels of inputs that may be used to measure fair value. The input levels are: Level 1: Quoted (observable) market prices in active markets for identical assets or liabilities. Level 2: Inputs other than Level 1 that are observable, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability. Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the asset or liability. Business and Credit Concentrations: Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash, cash equivalents, trade accounts receivable and derivative instruments, specifically related to counterparties. In accordance with the Company’s investment policy, the Company’s cash, cash equivalents and derivative instruments were placed with recognized financial institutions. The Company’s investment policy limits the amount of credit exposure in any one issue and the maturity date of the investment securities that typically comprise investment grade short-term debt instruments. Concentrations of credit risk in accounts receivable resulting from sales to major customers are discussed in Note 11, "Reportable Segments, Geographic Information and Major Customers". The Company, at times, requires cash deposits for services performed. The Company also closely monitors extensions of credit. Recently Adopted Accounting Pronouncements: In November 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-18 to address the classifications and presentation of changes in restricted cash in the statement of cash flows. The Company adopted this guidance retrospectively during the first quarter of fiscal 2017 and, as a result, the Company has included restricted cash within the Consolidated Statements of Cash Flows; such amounts were not material. The retrospective adoption did not impact the prior period Consolidated Statements of Cash Flows since there was no restricted cash during any of the prior periods presented. Amounts included in restricted cash represent cash received from customers to settle invoices sold under the trade accounts receivable sale programs that is contractually required to be set aside. The restrictions will lapse when the cash is remitted to the purchaser of the receivables. In March 2016, the FASB issued ASU 2016-09, which changes the accounting for certain aspects of share-based payments to employees. The guidance requires the recognition of the income tax effects of awards in the income statement when the awards vest or are settled, thus eliminating additional paid-in capital pools. The guidance also allows for the employer to repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting. In addition, the guidance allows for a policy election to account for forfeitures as they occur rather than on an estimated basis. The Company adopted this guidance prospectively during the first fiscal quarter of 2017. Upon adoption, the Company recognized no net impact to its fiscal 2017 opening retained earnings balance as an incremental $4.9 million net operating loss carryforward related to tax deductions in excess of compensation expense for stock options was fully offset by an increase to the valuation allowance. The adoption did not have any other material impacts and will not materially impact the Company's future financial statements as long as the Company remains in a valuation allowance in the jurisdictions in which share-based compensation awards and options vest and are exercised, respectively. Recently Issued Accounting Pronouncements Not Yet Adopted: In August 2017, the FASB issued ASU 2017-12 related to the accounting for hedging activities. The pronouncement expands and refines hedge accounting, aligns the recognition and presentation of the effects of hedging instruments and hedge items in the financial statements, and includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. This guidance is effective for the Company beginning in the first quarter of fiscal year 2020 and early adoption is permitted. The Company is finalizing its assessment of the impact of the guidance, but does not believe it will have a material impact on the Company's Consolidated Financial Statements. In October 2016, the FASB issued ASU 2016-16 related to the income tax consequences of intra-entity transfers of assets other than inventory. The new standard eliminates the exception for an intra-entity transfer of an asset other than inventory and requires an entity to recognize the income tax consequences when the transfer occurs. This guidance is effective for the Company beginning in the first quarter of fiscal year 2019 and early adoption is permitted. This guidance should be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The Company is currently assessing the impact this new standard may have on its Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15 related to the classification of certain cash receipts and cash payments, which clarifies how entities should classify certain cash receipts and cash payments on the statement of cash flows. The new standard addresses certain issues where diversity in practice was identified. It also amends existing guidance, which is principles based and often requires judgment to determine the appropriate classification of cash flows as operating, investing or financing activities and clarifies how the predominance principle should be applied when cash receipts and cash payments have aspects of more than one class of cash flows. This guidance is effective for the Company beginning in the first quarter of fiscal year 2019, and will generally require retrospective adoption. Early adoption is permitted. The Company is currently assessing the impact this new standard may have on its Consolidated Statements of Cash Flows. In February 2016, the FASB issued ASU 2016-02, which requires lessees to recognize most leases on their balance sheets but record expenses on their income statements in a manner similar to current accounting. For lessors, the guidance modifies the classification criteria and the accounting for sales-type and direct financing leases. The guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. Early adoption is permitted. The Company is currently in the process of assessing the impact of the adoption of the new standard on its Consolidated Financial Statements and the timing of adoption. In May 2014, the FASB issued ASU 2014-09, which requires an entity to recognize revenue relating to contracts with customers that depicts the transfer of promised goods or services to customers in an amount reflecting the consideration to which the entity expects to be entitled in exchange for such goods or services ("Topic 606"). Topic 606 also requires disclosures enabling users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers and is effective for the Company beginning in the first quarter of fiscal year 2019. The Company developed a comprehensive project plan that includes a global cross-functional team of representatives to conduct an assessment of Topic 606 and its potential impacts on the Company. The project plan includes analyzing the standard’s impact on the Company’s various revenue streams, comparing its historical accounting policies and practices to the requirements of the new standard, and identifying potential differences from applying the requirements of the new standard to its contracts. The Company is in the process of identifying and implementing appropriate changes to its current accounting policies, business processes, systems and controls to support revenue recognition and disclosures under Topic 606. As of September 30, 2017 , the Company has determined that the new standard will result in a change to the timing of revenue recognition for a significant portion of the Company's revenue, whereby revenue will be recognized "over time," as products are produced, as opposed to at a "point in time" upon physical delivery. The new standard could have a material impact on the Company's consolidated financial statements upon initial adoption, primarily as the Company recognizes an increase in contract assets for unbilled receivables with a corresponding reduction in finished goods and work-in-process inventory. The Company presently expects to adopt Topic 606 at the beginning of fiscal 2019 using the modified retrospective approach. The Company believes that no other recently issued accounting standards will have a material impact on its Consolidated Financial Statements, or apply to its operations.

Inventories

Inventories	12 Months Ended
	Sep. 30, 2017
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories as of September 30, 2017 and October 1, 2016 consisted of the following (in thousands): 2017 2016 Raw materials $ 477,921 $ 414,303 Work-in-process 86,367 69,423 Finished goods 90,354 80,405 Total inventories $ 654,642 $ 564,131 In certain circumstances, per contractual terms, customer deposits are received by the Company to offset obsolete and excess inventory risks. The total amount of customer deposits related to inventory and included within current liabilities on the accompanying Consolidated Balance Sheets as of September 30, 2017 and October 1, 2016 was $106.2 million and $74.6 million , respectively.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Sep. 30, 2017
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment as of September 30, 2017 and October 1, 2016 consisted of the following (in thousands): 2017 2016 Land, buildings and improvements $ 262,428 $ 247,806 Machinery and equipment 348,593 336,378 Computer hardware and software 117,404 107,239 Construction in progress 12,790 4,298 Total property, plant and equipment, gross 741,215 695,721 Less: accumulated depreciation (426,550 ) (404,496 ) Total property, plant and equipment, net $ 314,665 $ 291,225 Assets held under capital leases and included in property, plant and equipment as of September 30, 2017 and October 1, 2016 consisted of the following (in thousands): 2017 2016 Buildings and improvements $ 23,717 $ 12,801 Machinery and equipment 11,070 6,070 Total property, plant and equipment held under capital leases, gross 34,787 18,871 Less: accumulated amortization (6,465 ) (8,042 ) Total property, plant and equipment held under capital leases, net $ 28,322 $ 10,829 During fiscal 2017, the Company capitalized $15.7 million of certain leased property, plant and equipment related to the relocation of its Neenah Design Center to a new facility located near the Company's Global Headquarters. Amortization of assets held under capital leases totaled $3.0 million , $1.9 million and $0.5 million for fiscal 2017 , 2016 and 2015 , respectively. Capital lease additions totaled $20.5 million , $2.9 million , and $1.2 million for fiscal 2017 , 2016 and 2015 , respectively. As of September 30, 2017 , October 1, 2016 and October 3, 2015 , accounts payable included approximately $10.8 million , $3.5 million and $2.7 million , respectively, related to the purchase of property, plant and equipment, which have been treated as non-cash transactions for purposes of the Consolidated Statements of Cash Flows.

Debt, Capital Lease Obligations

Debt, Capital Lease Obligations and Other Financing	12 Months Ended
	Sep. 30, 2017
Debt and Capital Lease Obligations [Abstract]
Debt, Capital Lease Obligations and Other Financing	Debt, Capital Lease Obligations and Other Financing Debt and capital lease obligations as of September 30, 2017 and October 1, 2016 , consisted of the following (in thousands): 2017 2016 Borrowings under the credit facility $ 108,000 $ 75,000 5.20% Senior notes, due June 15, 2018 175,000 175,000 Capital lease and other financing obligations 30,901 13,614 Unamortized deferred financing fees (794 ) (1,105 ) Total obligations 313,107 262,509 Less: current portion (286,934 ) (78,507 ) Long-term debt and capital lease obligations, net of current portion $ 26,173 $ 184,002 The Company has a senior unsecured revolving credit facility (the "Credit Facility"), with a $300.0 million maximum commitment that expires on July 5, 2021 . The Credit Facility may be further increased to $500.0 million , generally by mutual agreement of the Company and the lenders, subject to certain customary conditions. During fiscal 2017, the highest daily borrowing was $151.0 million ; the average daily borrowings were $106.7 million . The Company borrowed $331.0 million and repaid $298.0 million of revolving borrowings under the Credit Facility during fiscal 2017. The financial covenants (as defined under the related Credit Agreement) require that the Company maintain, as of each fiscal quarter end, a maximum total leverage ratio and a minimum interest coverage ratio. As of September 30, 2017 , the Company was in compliance with all financial covenants of the Credit Agreement. Borrowings under the Credit Facility bear interest, at the Company’s option, at a eurocurrency or base rate plus, in each case, an applicable interest rate margin based on the Company’s then-current leverage ratio (as defined in the Credit Agreement). As of September 30, 2017 , the borrowing rate under the Credit Agreement was LIBOR plus 1.125% (or 2.358% ). The Company is required to pay an annual commitment fee on the unused revolver credit commitment based on the Company's leverage ratio; the fee was 0.175% as of September 30, 2017 . The Company also has outstanding 5.20% Senior Notes, due on June 15, 2018 (the "Notes"). As of September 30, 2017 and October 1, 2016 , $175.0 million was outstanding, and the Company was in compliance with all financial covenants relating to the Notes, which are generally consistent with those in the Credit Agreement discussed above. The aggregate scheduled maturities of the Company’s debt obligations as of September 30, 2017 , are as follows (in thousands): 2018 $ 283,000 2019 — 2020 — 2021 — 2022 — Thereafter — Total $ 283,000 The aggregate scheduled maturities of the Company’s capital leases and other financing obligations as of September 30, 2017 , are as follows (in thousands): 2018 $ 3,934 2019 2,705 2020 1,648 2021 820 2022 651 Thereafter 21,143 Total $ 30,901 The Company's weighted average interest rate on capital lease obligations was 4.51% and 5.58% as of September 30, 2017 and October 1, 2016 , respectively. The Neenah Design Center capital lease that commenced during fiscal 2017 resulted in a non-cash transaction of approximately $15.7 million and is reflected in the current portion of long-term debt and capital lease obligations, as well as in long-term debt and capital lease obligations, net of current portion, on the accompanying Consolidated Balance Sheets as of September 30, 2017 . The "Thereafter" line of the scheduled maturities of capital lease obligations table above includes an $8.6 million non-cash financing obligation related to a failed sale-leaseback of a building shell in Guadalajara, Mexico that was capitalized in fiscal 2014. This obligation will be increased by interest expense and land rent expense, and reduced by contractual payments during the 20 -year lease term. As of October 1, 2016 , the balance of the related financing obligation totaled $8.4 million . At the end of the 20 -year lease term, the net book value of the assets will approximate the balance of the financing obligation. If the Company does not exercise both renewal options or exercises the first but not the second, it would record a loss related to the disposal of the underlying assets in operating results of $4.1 million in fiscal 2024 or $0.8 million in fiscal 2029. The future minimum payments under the remainder of the ten -year base lease agreement, as well as the two five -year renewal options, are as follows (in thousands): 2018 $ 1,513 2019 1,550 2020 1,589 2021 1,629 2022 1,670 2023 through 2024 (remainder of the ten-year base lease agreement) 3,466 $ 11,417 2025 through 2029 (first five-year renewal option) 9,451 2030 through 2034 (second five-year renewal option) 10,870 Total $ 31,738

Derivatives and Fair Value Meas

Derivatives and Fair Value Measurements	12 Months Ended
	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Fair Value Measurements	Derivatives and Fair Value Measurements All derivatives are recognized in the accompanying Consolidated Balance Sheets at their estimated fair value. The Company uses derivatives to manage the variability of foreign currency obligations. The Company has cash flow hedges related to forecasted foreign currency obligations, in addition to non-designated hedges to manage foreign currency exposures associated with certain foreign currency denominated assets and liabilities. The Company does not enter into derivatives for speculative purposes. Generally accepted accounting principles require companies to recognize all derivative instruments as either assets or liabilities at fair value in the statement of financial position. Accordingly, the Company designates some foreign currency exchange contracts as cash flow hedges of forecasted foreign currency expenses. Changes in the fair value of the derivatives that qualify as cash flow hedges are recorded in "Accumulated other comprehensive loss" in the accompanying Consolidated Balance Sheets until earnings are affected by the variability of the cash flows. In the next twelve months, the Company estimates that $2.0 million of unrealized gains , net of tax, related to cash flow hedges will be reclassified from other comprehensive income (loss) into earnings. Changes in the fair value of the non-designated derivatives related to recognized foreign currency denominated assets and liabilities are recorded in "Miscellaneous income (expense)" in the accompanying Consolidated Statements of Comprehensive Income. The Company enters into forward currency exchange contracts for its Malaysian operations on a rolling basis. The Company had cash flow hedges outstanding with a notional value of $67.0 million as of September 30, 2017 , and a notional value of $73.7 million as of October 1, 2016 . These forward currency contracts fix the exchange rates for the settlement of future foreign currency obligations that have yet to be realized. The total fair value of the forward currency exchange contracts was a $2.0 million asset as of September 30, 2017 and a $0.5 million liability as of October 1, 2016 . The Company had additional forward currency exchange contracts outstanding as of September 30, 2017 , with a notional value of $10.6 million ; there were $109.6 million such contracts outstanding as of October 1, 2016 . The Company did not designate these derivative instruments as hedging instruments. The net settlement amount (fair value) related to these contracts is recorded on the Consolidated Balance Sheets as either a current or long-term asset or liability, depending on the term, and as an element of "Miscellaneous income (expense)." The total fair value of these derivatives was a $0.1 million liability as of September 30, 2017 , and a $0.1 million asset as of October 1, 2016 . On May 5, 2017, a $75.0 million notional amount interest rate swap contract expired related to $75.0 million of borrowings outstanding under the Credit Facility. The interest rate swap paid the Company variable interest at the one month LIBOR rate, and the Company paid the counterparty a fixed interest rate. The fixed interest rate for the contract was 0.875% . The interest rate swap contract qualified as a cash flow hedge and all changes in the fair value of the interest rate swap were recorded in "Accumulated other comprehensive loss" on the accompanying Consolidated Balance Sheets until earnings were affected by the variability of cash flows. The notional amount of the Company's interest rate swap was $75.0 million as of October 1, 2016 . The tables below present information regarding the fair values of derivative instruments (as defined in Note 1, "Description of Business and Significant Accounting Policies") and the effects of derivative instruments on the Company’s Consolidated Financial Statements: Fair Values of Derivative Instruments In thousands of dollars Asset Derivatives Liability Derivatives September 30, October 1, September 30, October 1, Derivatives designated as hedging instruments Balance Sheet Classification Fair Value Fair Value Balance Sheet Classification Fair Value Fair Value Interest rate swaps Prepaid expenses and other $ — $ — Other accrued liabilities $ — $ 132 Forward currency forward contracts Prepaid expenses and other $ 2,024 $ — Other accrued liabilities $ — $ 486 Fair Values of Derivative Instruments In thousands of dollars Asset Derivatives Liability Derivatives September 30, October 1, September 30, October 1, Derivatives not designated as hedging instruments Balance Sheet Classification Fair Value Fair Value Balance Sheet Classification Fair Value Fair Value Forward currency forward contracts Prepaid expenses and other $ 35 $ 182 Other accrued liabilities $ 118 $ 130 Derivative Impact on Accumulated Other Comprehensive Loss ("OCL") for the Twelve Months Ended In thousands of dollars Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion) September 30, 2017 October 1, 2016 October 3, 2015 Interest rate swaps $ (10 ) $ (16 ) $ (1,258 ) Forward currency forward contracts $ (848 ) $ 5,311 $ (15,660 ) Derivative Impact on Gain (Loss) Recognized in Income for the Twelve Months Ended In thousands of dollars Derivatives in Cash Flow Hedging Relationships Classification of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion) September 30, 2017 October 1, 2016 October 3, 2015 Interest rate swaps Interest expense $ (142 ) $ (381 ) $ (579 ) Forward currency forward contracts Selling and administrative expenses $ (317 ) $ (350 ) $ (597 ) Forward currency forward contracts Cost of sales $ (3,041 ) $ (3,261 ) $ (4,843 ) Treasury Rate Locks Interest expense $ 321 $ 320 $ 324 Interest rate swaps Income tax expense $ (84 ) $ — $ — Derivatives Not Designated as Hedging Instruments Location of Gain Recognized on Derivatives in Income Amount of Gain on Derivatives Recognized in Income September 30, 2017 October 1, 2016 October 3, 2015 Forward currency forward contracts Miscellaneous income (expense) $ 2,153 $ 121 $ 164 There were no gains or losses recognized in income for derivatives related to ineffective portions and amounts excluded from effectiveness testing for fiscal years 2017 , 2016 and 2015 . The following table lists the fair values of liabilities of the Company’s derivatives as of September 30, 2017 and October 1, 2016 , by input level as defined in Note 1, "Description of Business and Significant Accounting Policies": Fair Value Measurements Using Input Levels Asset/(Liability) In thousands of dollars Fiscal year ended September 30, 2017 Level 1 Level 2 Level 3 Total Derivatives Forward currency forward contracts $ — $ 1,941 $ — $ 1,941 Fiscal year ended October 1, 2016 Derivatives Interest rate swaps $ — $ (132 ) $ — $ (132 ) Forward currency forward contracts $ — $ (434 ) $ — $ (434 ) The fair value of interest rate swaps and foreign currency forward contracts is determined using a market approach, which includes obtaining directly or indirectly observable values from third parties active in the relevant markets. The primary input in the fair value of the interest rate swaps is the relevant LIBOR forward curve. Inputs in the fair value of the foreign currency forward contracts include prevailing forward and spot prices for currency and interest rate forward curves.

Income Taxes

Income Taxes	12 Months Ended
	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The domestic and foreign components of income (loss) before income tax expense for fiscal 2017 , 2016 and 2015 were as follows (in thousands): 2017 2016 2015 U.S. $ (35,209 ) $ (26,796 ) $ (32,480 ) Foreign 157,032 114,190 138,775 $ 121,823 $ 87,394 $ 106,295 Income tax expense (benefit) for fiscal 2017 , 2016 and 2015 were as follows (in thousands): 2017 2016 2015 Current: Federal $ 78 $ — $ — State 33 (15 ) (397 ) Foreign 10,016 11,312 12,957 10,127 11,297 12,560 Deferred: Federal 77 — — State 38 24 (399 ) Foreign (481 ) (354 ) (198 ) (366 ) (330 ) (597 ) $ 9,761 $ 10,967 $ 11,963 The following is a reconciliation of the federal statutory income tax rate to the effective income tax rates reflected in the Consolidated Statements of Comprehensive Income for fiscal 2017 , 2016 and 2015 : 2017 2016 2015 Federal statutory income tax rate 35.0 % 35.0 % 35.0 % Increase (decrease) resulting from: Permanent differences 1.2 1.6 1.3 Foreign tax rate differences (39.9 ) (36.3 ) (38.0 ) Disregarded entity benefit (0.9 ) (1.8 ) (1.2 ) Dividend repatriation — 32.9 — Valuation allowances 12.2 (18.7 ) 16.5 Other, net 0.4 (0.1 ) (2.3 ) Effective income tax rate 8.0 % 12.6 % 11.3 % The Company recorded income tax expense of $9.8 million , $11.0 million and $12.0 million for fiscal 2017 , 2016 and 2015 , respectively. The effective tax rate for fiscal 2017 was lower than the effective tax rate for fiscal 2016 primarily due to an increase in income before taxes in lower tax-rate jurisdictions and a tax benefit related to incremental deductible expenses in a jurisdiction where the Company pays income taxes. The effective tax rate for fiscal 2016 is higher than that of fiscal 2015 primarily as a result of the overall decrease in income before taxes in jurisdictions where the Company does not pay taxes. During fiscal 2017, the Company recorded a $14.9 million addition to its valuation allowance relating to continuing losses in certain jurisdictions within the AMER and EMEA regions. During fiscal 2016, the Company repatriated $100.0 million of current year foreign earnings from the APAC region to the U.S., which had no income statement impact due to U.S. net operating losses, the use of U.S. tax credits and the reversal of the related valuation allowance. The repatriation does not impact the permanently reinvested assertions made by the Company regarding prior period foreign earnings as the remittance was distributed exclusively from current year foreign earnings. The Company does not have a history of repatriating foreign earnings by way of a taxable dividend and considers the fiscal 2016 remittance to be an isolated occurrence. Without tax reform, the Company does not anticipate a similar repatriation in the foreseeable future. During fiscal 2015, the Company recorded a $17.5 million addition to its valuation allowance related to continuing losses in certain jurisdictions within the AMER and EMEA regions. The components of the net deferred income tax assets as of September 30, 2017 and October 1, 2016 , were as follows (in thousands): 2017 2016 Deferred income tax assets: Loss/credit carryforwards $ 44,831 $ 24,017 Inventories 7,710 7,527 Accrued benefits 25,811 25,493 Allowance for bad debts 319 461 Other 2,732 2,822 Total gross deferred income tax assets 81,403 60,320 Less valuation allowances (61,668 ) (41,002 ) Deferred income tax assets 19,735 19,318 Deferred income tax liabilities: Property, plant and equipment 14,443 14,400 Other — 84 Deferred income tax liabilities 14,443 14,484 Net deferred income tax assets $ 5,292 $ 4,834 During the first fiscal quarter of 2017, the Company adopted ASU 2016-09. Upon adoption, the Company recognized no net impact to its fiscal 2017 opening retained earnings balance as an incremental $4.9 million net operating loss carryforward related to tax deductions in excess of compensation expense for stock options was fully offset by an increase to the valuation allowance. During fiscal 2017 , the Company’s valuation allowance increased by $20.7 million . This increase is the result of increases to the valuation allowances against the net deferred tax assets in the AMER region of $18.4 million and in the EMEA region of $2.3 million . As of September 30, 2017 , the Company had approximately $181.5 million of pre-tax state net operating loss carryforwards that expire between fiscal 2018 and 2038. These state net operating losses have a full valuation allowance against them. During fiscal 2017 , tax legislation was adopted in various jurisdictions. None of the legislative changes are expected to have a material impact on the Company's consolidated financial condition, results of operations or cash flows. The Company has been granted a tax holiday for a foreign subsidiary in the APAC region. This tax holiday will expire on December 31, 2024 , and is subject to certain conditions with which the Company expects to comply. During fiscal 2017 , 2016 and 2015 , the tax holiday resulted in tax reductions of approximately $37.5 million ( $1.11 per basic share, $1.08 per diluted share), $27.1 million ( $0.81 per basic share, $0.79 per diluted share) and $29.9 million ( $0.89 per basic share, $0.87 per diluted share), respectively. The Company does not provide for taxes that would be payable if undistributed earnings of foreign subsidiaries were remitted because the Company considers these earnings to be permanently reinvested. The aggregate undistributed earnings of the Company’s foreign subsidiaries for which a deferred income tax liability has not been recorded was approximately $990.7 million as of September 30, 2017 . If such earnings were repatriated, additional tax expense may result, although the calculation of such additional taxes is not practicable at this time. The Company has approximately $3.1 million of uncertain tax benefits as of September 30, 2017 . The Company has classified these amounts in the Consolidated Balance Sheets as "Other liabilities" (noncurrent) in the amount of $0.8 million and an offset to "Deferred income taxes" (noncurrent asset) in the amount of $2.3 million . The Company has classified these amounts as "Other liabilities" (noncurrent) and "Deferred income taxes" (noncurrent asset) to the extent that payment is not anticipated within one year. The following is a reconciliation of the beginning and ending amounts of unrecognized income tax benefits (in thousands): 2017 2016 2015 Balance at beginning of fiscal year $ 2,799 $ 2,353 $ 2,368 Gross increases for tax positions of prior years 184 534 73 Gross increases for tax positions of the current year 163 — — Gross decreases for tax positions of prior years (31 ) (88 ) (88 ) Balance at end of fiscal year $ 3,115 $ 2,799 $ 2,353 The amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate is $0.8 million and $0.6 million for the fiscal years ended September 30, 2017 and October 1, 2016 , respectively. The Company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense. The total accrued penalties and net accrued interest with respect to income taxes was approximately $0.2 million for each of the fiscal years ended September 30, 2017 , October 1, 2016 and October 3, 2015 . The Company recognized less than $0.1 million of expense for accrued penalties and net accrued interest in the Consolidated Statements of Comprehensive Income for each of the fiscal years ended September 30, 2017 , October 1, 2016 and October 3, 2015 . It is possible that a number of uncertain tax positions may be settled within the next 12 months. Settlement of these matters is not expected to have a material effect on the Company’s consolidated results of operations, financial position and cash flows. The Company files income tax returns, including returns for its subsidiaries, with federal, state, local and foreign taxing jurisdictions. The following tax years remain subject to examination by the respective major tax jurisdictions: Jurisdiction Fiscal Years China 2012-2017 Germany 2013-2017 Mexico 2012-2017 Romania 2011-2017 United Kingdom 2014-2017 United States Federal 2011, 2013-2017 State 2003-2017

Earnings Per Share

Earnings Per Share	12 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following is a reconciliation of the amounts utilized in the computation of basic and diluted earnings per share for fiscal 2017 , 2016 and 2015 (in thousands, except per share amounts): 2017 2016 2015 Net income $ 112,062 $ 76,427 $ 94,332 Basic weighted average common shares outstanding 33,612 33,374 33,618 Dilutive effect of share-based awards outstanding 941 724 761 Diluted weighted average shares outstanding 34,553 34,098 34,379 Earnings per share: Basic $ 3.33 $ 2.29 $ 2.81 Diluted $ 3.24 $ 2.24 $ 2.74 In fiscal 2017 , 2016 and 2015 , share-based awards for approximately 0.1 million , 0.8 million and 0.7 million shares, respectively, were not included in the computation of diluted earnings per share as they were antidilutive.

Operating Lease Commitments

Operating Lease Commitments	12 Months Ended
	Sep. 30, 2017
Leases, Operating [Abstract]
Operating Lease Commitments	Operating Lease Commitments The Company has a number of operating lease agreements primarily involving manufacturing facilities, manufacturing equipment and computerized design equipment. These leases are non-cancelable and expire on various dates through fiscal 2027, and many contain renewal and/or purchase options. Rent expense under all operating leases for fiscal 2017 , 2016 and 2015 was approximately $13.7 million , $13.6 million and $14.4 million , respectively. Future minimum annual payments on operating leases are as follows (in thousands): 2018 $ 9,390 2019 8,191 2020 7,873 2021 4,279 2022 1,718 Thereafter 5,106 Total future minimum operating lease payments $ 36,557

Benefit Plans

Benefit Plans	12 Months Ended
	Sep. 30, 2017
Compensation Related Costs [Abstract]
Benefit Plans	Benefit Plans Share-based Compensation Plans: The Plexus Corp. 2016 Omnibus Incentive Plan (the "2016 Plan"), which was approved by shareholders, is a stock and cash-based incentive plan, and includes provisions by which the Company may grant executive officers, employees and directors stock options, stock appreciation rights ("SARs"), restricted stock (including restricted stock units ("RSUs"), performance stock awards (including performance stock units ("PSUs"), other stock awards and cash incentive awards. Similar awards were offered under its predecessor, the 2008 Long-Term Incentive Plan (the "2008 Plan"), which is no longer being used for grants; however, outstanding awards granted under the 2008 Plan and its predecessors continue in accordance with their terms. The maximum number of shares of Plexus common stock that may be issued pursuant to the 2016 Plan is 3.2 million shares; in addition, cash incentive awards of up to $4.0 million per employee may be granted annually. The exercise price of each stock option and SAR granted must not be less than the fair market value on the date of grant. The Compensation and Leadership Development Committee (the "Committee") of the Board of Directors may establish a term and vesting period for awards under the 2016 Plan as well as accelerate the vesting of such awards. Generally, stock options vest in two annual installments and have a term of ten years . SARs vest in two annual installments and have a term of seven years . RSUs granted to executive officers, other officers and key employees generally vest on the third anniversary of the grant date (assuming continued employment), which is also the date as of which the underlying shares will be issued. Beginning for fiscal 2017 grants, 50% of PSUs vest based on the relative total shareholder return ("TSR") of the Company's common stock as compared to the companies in the Russell 3000 Index, a market condition, and the remaining 50% vest based upon a three-point annual average of the Company's absolute economic return, a performance condition, each during a three -year performance period. The PSUs granted in fiscal 2016 and prior years vest based solely on the relative TSR of the Company's common stock as compared to companies in the Russell 3000 Index during a three -year performance period. The Committee also grants RSUs to non-employee directors, which generally fully vest on the first anniversary of the grant date, which is also the date the underlying shares are issued (unless further deferred). The Company recognized $17.4 million , $19.3 million and $13.3 million of compensation expense associated with share-based awards in fiscal 2017 , 2016 and 2015 , respectively. No deferred tax benefits related to equity awards were recognized in fiscal 2017 , 2016 or 2015 . A summary of the Company’s stock option and SAR activity follows: Number of Options/SARs (in thousands) Weighted Average Exercise Price Aggregate Intrinsic Value (in thousands) Outstanding as of September 27, 2014 2,270 $ 31.65 Granted 221 39.53 Canceled (25 ) 36.50 Exercised (549 ) 28.93 Outstanding as of October 3, 2015 1,917 $ 33.27 Granted 229 39.52 Canceled (66 ) 41.48 Exercised (619 ) 31.59 Outstanding as of October 1, 2016 1,461 $ 34.59 Granted 36 45.45 Canceled (4 ) 30.88 Exercised (521 ) 32.29 Outstanding as of September 30, 2017 972 $ 36.23 $ 19,283 Number of Options/SARs (in thousands) Weighted Average Exercise Price Weighted Average Remaining Life (years) Aggregate Intrinsic Value (in thousands) Exercisable as of: October 3, 2015 1,560 $ 31.67 October 1, 2016 1,125 $ 33.11 September 30, 2017 865 $ 35.62 4.21 $ 17,692 The following table summarizes outstanding stock option and SAR information as of September 30, 2017 (Options/SARs in thousands): Range of Exercise Prices Number of Options/SARs Outstanding (in thousands) Weighted Average Exercise Price Weighted Average Remaining Life (years) Number of Options / SARs Exercisable (in thousands) Weighted Average Exercise Price $14.17 - $31.70 244 $ 26.27 3.40 244 $ 26.27 $31.71 - $37.12 279 $ 35.56 5.00 243 $ 35.72 $37.13 - $41.84 270 $ 40.11 4.92 252 $ 39.99 $41.85 - $45.45 179 $ 44.99 5.68 126 $ 44.81 $14.17 - $45.45 972 $ 36.23 4.70 865 $ 35.62 The Company uses the Black-Scholes valuation model to value options and SARs. The Company used its historical stock prices as the basis for its volatility assumptions. The assumed risk-free rates were based on U.S. Treasury rates in effect at the time of grant with a term consistent with the expected option and SAR lives. The expected options and SARs lives represent the period of time that the options and SARs granted are expected to be outstanding and were based on historical experience. The weighted average fair value per share of options and SARs granted for fiscal 2017 , 2016 and 2015 were $15.66 , $12.82 and $14.55 , respectively. The fair value of each option and SAR grant was estimated at the date of grant using the Black-Scholes option-pricing model based on the assumption ranges below: 2017 2016 2015 Expected life (years) 5.70 5.70 4.50 - 5.70 Risk-free interest rate 1.50% 1.23 - 1.87% 1.52 - 1.64% Expected volatility 34% 35 - 37% 37 - 38% Dividend yield — — — The fair value of options and SARs vested for fiscal 2017 , 2016 and 2015 was $3.5 million , $3.6 million and $5.5 million , respectively. For fiscal 2017 , 2016 and 2015 , the total intrinsic value of options and SARs exercised was $10.2 million , $7.4 million and $7.7 million , respectively. As of September 30, 2017 , there was $0.7 million of unrecognized compensation expense related to non-vested options and SARs that is expected to be recognized over a weighted average period of 0.7 years . A summary of the Company’s PSU and RSU activity follows: Number of Shares (in thousands) Weighted Average Fair Value at Date of Grant Aggregate Intrinsic Value (in thousands) Units outstanding as of September 27, 2014 730 $ 31.97 Granted 325 41.46 Canceled (43 ) 35.15 Vested (216 ) 37.52 Units outstanding as of October 3, 2015 796 $ 38.18 Granted 499 39.68 Canceled (29 ) 36.84 Vested (244 ) 27.77 Units outstanding as of October 1, 2016 1,022 $ 41.49 Granted 397 54.21 Canceled (22 ) 41.17 Vested (329 ) 43.76 Units outstanding as of September 30, 2017 1,068 $ 45.97 $ 59,905 The Company uses the fair value at the date of grant to value RSUs. As of September 30, 2017 , there was $16.6 million of unrecognized compensation expense related to RSUs that is expected to be recognized over a weighted average period of 1.5 years . The Company uses the Monte Carlo valuation model to determine the fair value of PSUs at the date of grant. Vesting of all PSUs granted in fiscal 2016 and prior years is based on the relative TSR of Plexus stock as compared to the TSR of companies in the Russell 3000 Index during a three -year performance period. Beginning in fiscal 2017, 50% of the PSUs will vest based on relative TSR performance, with the other 50% vesting based on a three-point annual average of the Company's absolute economic return, each during a three -year performance period. The vesting and payout of awards will range between 0% and 200% of the shares granted based upon performance on the metrics during the performance period. Payout at target, 100% of the shares granted, will occur if the TSR of Plexus stock is at the 50 th percentile of companies in the Russell 3000 Index during the performance period and if a 2.5% average economic return is achieved over the three -year performance period. The number of shares that may be issued pursuant to PSUs ranges from zero to 0.4 million . The Company recognizes share-based compensation expense over the vesting period of PSUs. During the fiscal year ended September 30, 2017 , the 0.1 million PSUs granted in fiscal 2014 vested at a 98% payout based upon the TSR performance achieved during the performance period. There were 0.1 million PSUs granted during each of fiscal years 2017 , 2016 and 2015 . As of September 30, 2017 , at the target achievement level, there was $4.4 million of unrecognized compensation expense related to PSUs that is expected to be recognized over a weighted average period of 2.1 years . 401(k) Savings Plan: The Company’s 401(k) Retirement Plan covers all eligible U.S. employees. The Company matches employee contributions up to 4.0% of eligible earnings. The Company’s contributions for fiscal 2017 , 2016 and 2015 totaled $7.5 million , $7.4 million and $7.2 million , respectively. Deferred Compensation Arrangements: The Company has agreements with certain former executive officers to provide nonqualified deferred compensation. Under these agreements, the Company agrees to pay these former executives, or their designated beneficiaries upon such executives’ deaths, certain amounts annually for the first 15 years subsequent to their retirement. As of September 30, 2017 and October 1, 2016 , the related deferred compensation liability associated with these arrangements totaled $0.3 million and $0.6 million , respectively. The Company maintains investments in a trust account to fund required payments under the deferred compensation plan. As of September 30, 2017 and October 1, 2016 , the total value of the assets held by the trust totaled $9.7 million and $9.3 million , respectively, and was recorded at fair value on a recurring basis. These assets were classified as Level 2 in the fair value hierarchy discussed in Note 1, "Description of Business and Significant Accounting Policies." During fiscal 2017 , 2016 and 2015 , the Company made payments to the participants in the amount of $0.4 million , $0.8 million and $0.9 million , respectively. Supplemental Executive Retirement Plan: The Company also maintains a supplemental executive retirement plan (the "SERP") as an additional deferred compensation plan for executive officers. Under the SERP, a covered executive may elect to defer some or all of the participant’s compensation into the plan, and the Company may credit the participant’s account with a discretionary employer contribution. Participants are entitled to payment of deferred amounts and any related earnings upon termination or retirement from Plexus. The SERP allows investment of deferred compensation into individual accounts and, within these accounts, into one or more designated investments. Investment choices do not include Plexus stock. During fiscal 2017 , 2016 and 2015 , the Company made contributions to the participants’ SERP accounts in the amount of $1.2 million , $0.5 million and $0.5 million , respectively. In March 2017, the Company changed the trustee of the SERP. The change resulted in a settlement and re-investment of $10.3 million , with no actual cash received or distributed by the Company. As of September 30, 2017 and October 1, 2016 , the SERP assets held in the trust totaled $12.0 million and $9.5 million , respectively, and the related liability to the participants totaled approximately $12.0 million and $9.8 million , respectively. As of September 30, 2017 and October 1, 2016 , the SERP assets held in the trust were recorded at fair value on a recurring basis, and were classified as Level 2 in the fair value hierarchy discussed in Note 1, "Description of Business and Significant Accounting Policies." The trust assets are subject to the claims of the Company’s creditors. The deferred compensation and trust assets and the related liabilities to the participants are included in non-current "Other assets" and non-current "Other liabilities," respectively, in the accompanying Consolidated Balance Sheets.

Litigation

Litigation	12 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Litigation	Litigation The Company is party to lawsuits in the ordinary course of business. Management does not believe that these proceedings, individually or in the aggregate, will have a material positive or adverse effect on the Company’s consolidated financial position, results of operations or cash flows.

Reportable Segments, Geographic

Reportable Segments, Geographic Information and Major Customers	12 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Reportable Segments, Geographic Information and Major Customers	Reportable Segments, Geographic Information and Major Customers Reportable segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker, or group, in assessing performance and allocating resources. The Company uses an internal management reporting system, which provides important financial data to evaluate performance and allocate the Company’s resources on a regional basis. Net sales for the segments are attributed to the region in which the product is manufactured or the service is performed. The services provided, manufacturing processes used, class of customers serviced and order fulfillment processes used are similar and generally interchangeable across the segments. A segment’s performance is evaluated based upon its operating income (loss). A segment’s operating income (loss) includes its net sales less cost of sales and selling and administrative expenses, but excludes corporate and other expenses. Corporate and other expenses primarily represent corporate selling and administrative expenses, and restructuring and other charges, if any. Losses incurred from a typhoon that impacted the APAC segment in fiscal 2016 are excluded from the segment results and included within corporate and other expenses. These costs are not allocated to the segments, as management excludes such costs when assessing the performance of the segments. Inter-segment transactions are generally recorded at amounts that approximate arm’s length transactions. The accounting policies for the segments are the same as for the Company taken as a whole. Information about the Company’s three reportable segments for fiscal 2017 , 2016 and 2015 is as follows (in thousands): 2017 2016 2015 Net sales: AMER $ 1,166,346 $ 1,328,760 $ 1,389,017 APAC 1,279,261 1,161,851 1,285,905 EMEA 192,829 170,450 140,292 Elimination of inter-segment sales (110,384 ) (105,057 ) (160,924 ) $ 2,528,052 $ 2,556,004 $ 2,654,290 Operating income (loss): AMER $ 41,924 $ 64,921 $ 68,585 APAC 200,103 155,501 160,217 EMEA (6,197 ) (3,746 ) (8,129 ) Corporate and other costs (105,922 ) (117,237 ) (105,237 ) $ 129,908 $ 99,439 $ 115,436 Other income (expense): Interest expense (13,578 ) (14,635 ) (13,964 ) Interest income 5,042 4,242 3,499 Miscellaneous 451 (1,652 ) 1,324 Income before income taxes $ 121,823 $ 87,394 $ 106,295 Depreciation: AMER $ 19,694 $ 19,937 $ 17,753 APAC 15,588 16,874 18,176 EMEA 5,467 6,106 8,339 Corporate 4,581 4,497 4,110 $ 45,330 $ 47,414 $ 48,378 Capital expenditures: AMER $ 18,111 $ 14,389 $ 17,595 APAC 13,816 10,786 9,590 EMEA 5,748 3,399 6,976 Corporate 863 2,549 915 $ 38,538 $ 31,123 $ 35,076 September 30, October 1, Total assets: AMER $ 595,851 $ 590,850 APAC 1,163,111 1,009,917 EMEA 172,830 136,636 Corporate and eliminations 44,390 28,416 $ 1,976,182 $ 1,765,819 The following information is provided in accordance with the required segment disclosures for fiscal 2017 , 2016 and 2015 . Net sales were based on the Company’s location providing the product or service (in thousands): 2017 2016 2015 Net sales: United States $ 984,773 $ 1,134,342 $ 1,303,106 Malaysia 940,045 844,501 926,059 China 339,216 317,350 359,846 Mexico 181,573 194,418 85,911 Romania 114,363 83,712 65,338 United Kingdom 70,163 81,894 70,335 Germany 8,303 4,844 4,619 Elimination of inter-segment sales (110,384 ) (105,057 ) (160,924 ) $ 2,528,052 $ 2,556,004 $ 2,654,290 September 30, October 1, Long-lived assets: United States $ 110,828 $ 92,152 Malaysia 74,769 71,596 Mexico 37,237 39,155 Romania 33,717 30,408 China 18,602 19,197 United Kingdom 6,456 6,594 Germany 303 307 Other Foreign 5,126 4,940 Corporate 27,627 26,876 $ 314,665 $ 291,225 As the Company operates flexible manufacturing facilities and processes designed to accommodate customers with multiple product lines and configurations, it is impracticable to report net sales for individual products or services or groups of similar products and services. Long-lived assets as of September 30, 2017 and October 1, 2016 exclude other long-term assets and deferred income tax assets, which totaled $44.1 million and $41.2 million , respectively. As a percentage of consolidated net sales, net sales attributable to customers representing 10.0% or more of consolidated net sales for fiscal 2017 , 2016 and 2015 were as follows: 2017 2016 2015 General Electric Company ("GE") 12.2% 11.1% 10.6% Micron Technology, Inc. ("Micron") * 10.4% * ARRIS Group, Inc. ("Arris") * 10.1% 12.6% * Net sales attributable to the customer were less than 10.0% of consolidated net sales for the period. During fiscal 2017, 2016, and 2015, net sales attributable to GE were reported in all three reportable segments. During fiscal 2016 and 2015, sales attributable to Arris were reported in the AMER and APAC segments. During fiscal 2016, net sales attributable to Micron were reported in the AMER and APAC segments. As of September 30, 2017 , Arris represented 11.6% of total accounts receivable. As of October 1, 2016 , Micron represented 18.9% of total accounts receivable.

Guarantees

Guarantees	12 Months Ended
	Sep. 30, 2017
Guarantees [Abstract]
Guarantees	Guarantees The Company offers certain indemnifications under its customer manufacturing agreements. In the normal course of business, the Company may from time to time be obligated to indemnify its customers or its customers’ customers against damages or liabilities arising out of the Company’s negligence, misconduct, breach of contract, or infringement of third party intellectual property rights. Certain agreements have extended broader indemnification, and while most agreements have contractual limits, some do not. However, the Company generally does not provide for such indemnities and seeks indemnification from its customers for damages or liabilities arising out of the Company’s adherence to customers’ specifications or designs or use of materials furnished, or directed to be used, by its customers. The Company does not believe its obligations under such indemnities are material. In the normal course of business, the Company also provides its customers a limited warranty covering workmanship, and in some cases materials, on products manufactured by the Company. Such warranty generally provides that products will be free from defects in the Company’s workmanship and meet mutually agreed-upon specifications for periods generally ranging from 12 months to 24 months. The Company’s obligation is generally limited to correcting, at its expense, any defect by repairing or replacing such defective product. The Company’s warranty generally excludes defects resulting from faulty customer-supplied components, design defects or damage caused by any party or cause other than the Company. The Company provides for an estimate of costs that may be incurred under its limited warranty at the time product revenue is recognized and establishes additional reserves for specifically identified product issues. These costs primarily include labor and materials, as necessary, associated with repair or replacement and are included in the Company's accompanying Consolidated Balance Sheets in "other current accrued liabilities." The primary factors that affect the Company’s warranty liability include the value and the number of shipped units and historical and anticipated rates of warranty claims. As these factors are impacted by actual experience and future expectations, the Company assesses the adequacy of its recorded warranty liabilities and adjusts the amounts as necessary. Below is a table summarizing the activity related to the Company’s limited warranty liability for fiscal 2017 , 2016 and 2015 (in thousands): Limited warranty liability, as of September 27, 2014 6,803 Accruals for warranties issued during the period 1,742 Settlements (in cash or in kind) during the period (2,698 ) Limited warranty liability, as of October 3, 2015 5,847 Accruals for warranties issued during the period 1,777 Settlements (in cash or in kind) during the period (1,515 ) Limited warranty liability, as of October 1, 2016 6,109 Accruals for warranties issued during the period 912 Settlements (in cash or in kind) during the period (2,265 ) Limited warranty liability, as of September 30, 2017 4,756

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Sep. 30, 2017
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders' Equity On June 6, 2016, the Board of Directors authorized a multi-year stock repurchase program under which the Company is authorized to repurchase up to $150.0 million of its common stock beginning in fiscal 2017. During fiscal 2017 , the Company repurchased 655,470 shares under this program for $34.1 million , at an average price of $52.08 per share. On August 20, 2015, the Board of Directors authorized a stock repurchase program under which the Company was authorized to repurchase up to $30.0 million of its common stock during fiscal 2016. During fiscal 2016, the Company repurchased 760,903 shares for $30.0 million , at an average price of $39.43 per share. All shares repurchased under the aforementioned programs were recorded as treasury stock. Pursuant to the Company’s Rights Agreement, each preferred share purchase right (a "Right") entitles the registered holder to purchase from the Company one one-hundredth of a share of the Company’s Series B Junior Participating Preferred Stock, $0.01 par value per share ("Preferred Share"), at a price of $125.00 per one one-hundredth of a Preferred Share, subject to adjustment. The Rights are exercisable only if a person or group acquires beneficial ownership of more than 20.0% of the Company’s outstanding common stock or commences, or announces an intention to make, a tender offer or exchange offer that would result in such person or group acquiring the beneficial ownership of more than 20.0% of the Company’s common stock. The Rights expire on August 28, 2018 , subject to extension.

Trade Accounts Receivable Sale

Trade Accounts Receivable Sale Programs	12 Months Ended
	Sep. 30, 2017
Receivables [Abstract]
Trade Accounts Receivable Sale Programs	Trade Accounts Receivable Sale Programs The Company has a Master Accounts Receivable Purchase Agreement (the "BTMU RPA") with The Bank of Tokyo-Mitsubishi UFJ, Ltd., New York Branch (the "BTMU Purchaser"). Pursuant to the BTMU RPA, the Company and certain of its subsidiaries (each, a "Seller") may sell to the BTMU Purchaser accounts receivable owed to such Sellers by specified customers. In exchange, the BTMU Purchaser pays a purchase price for each purchased receivable equal to the net face value of the receivable less an agreed-upon discount. The BTMU RPA represents a non-committed facility. The BTMU Purchaser pays an agreed-upon servicing fee to each Seller with respect to each purchased receivable sold by such Seller, consistent with common market practices. The BTMU RPA contains representations, warranties, covenants, and termination events that are customary for factoring transactions of this type. The BTMU RPA was amended on October 19, 2017 to increase the maximum facility amount from $120.0 million to $160.0 million . The BTMU RPA is subject to expiration on October 3, 2018, but will be automatically extended each year unless any party gives no less than 10 days prior notice that the agreement should not be extended. On March 17, 2017, the Company entered into a Master Accounts Receivable Purchase Agreement (the "HSBC RPA") with HSBC Bank (China) Company Limited, Xiamen branch (the "HSBC Purchaser"). Pursuant to the HSBC RPA, the Company and certain of its subsidiaries (each, an "HSBC Seller") may sell to the HSBC Purchaser up to an aggregate of $60.0 million in accounts receivable owed to such HSBC Sellers by specified customers. The terms of the HSBC RPA are generally consistent with the terms of the BTMU RPA discussed above. The Company sold receivables under a former trade accounts receivable sale program that expired during the first fiscal quarter of 2017. Transfers of receivables under the programs are accounted for as sales and, accordingly, receivables sold under the programs are excluded from accounts receivable on the Consolidated Balance Sheets and are reflected as cash provided by operating activities on the Consolidated Statements of Cash Flows. Proceeds from the transfer reflect the face value of the receivables less a discount. The sale discount is recorded within "Miscellaneous expense" in the Consolidated Statements of Comprehensive Income in the period of the sale. The Company sold $418.0 million , $65.6 million and $93.1 million of trade accounts receivable under these programs, or their predecessors, during fiscal years 2017, 2016 and 2015, respectively, in exchange for cash proceeds of $415.8 million , $65.0 million and $92.4 million , respectively.

Restructuring and Other Charges

Restructuring and Other Charges	12 Months Ended
	Sep. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring and Other Charges	Restructuring and Other Charges The Company incurred no restructuring and other charges during fiscal 2017. During fiscal 2016 the Company recorded $7.0 million of restructuring and other charges related largely to the Company's closure of its manufacturing facility in Fremont, California. The Company also recorded restructuring and other charges in the EMEA segment related to the partial closure of its Livingston, Scotland facility. During fiscal 2015 the Company recorded $1.7 million of restructuring and other charges in the AMER segment, which largely related to the consolidation of the Company's manufacturing facilities in Wisconsin and the relocation of manufacturing operations from Juarez to Guadalajara, Mexico. These charges are recorded within "Restructuring and other charges" on the Consolidated Statements of Comprehensive Income. Restructuring liabilities are recorded within "Other accrued liabilities" in the Consolidated Balance Sheets. No income tax benefit for these restructuring and other charges was recognized due to tax losses in these jurisdictions. The Company's restructuring accrual activity for the years ended September 30, 2017 , October 1, 2016 and October 3, 2015 is included in the table below (in thousands): Employee Termination and Severance Costs Lease Obligations and Other Exit Costs Total Accrual balance, September 27, 2014 $ 142 $ — $ 142 Restructuring and other charges 144 1,547 1,691 Amounts utilized (286 ) (1,547 ) (1,833 ) Accrual balance, October 3, 2015 $ — $ — $ — Restructuring and other charges 5,255 1,779 7,034 Amounts utilized (4,571 ) (1,621 ) (6,192 ) Accrual balance, October 1, 2016 $ 684 $ 158 $ 842 Restructuring and other charges — — — Amounts utilized (684 ) (158 ) (842 ) Accrual balance, September 30, 2017 $ — $ — $ —

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Sep. 30, 2017
Quarterly Financial Data [Abstract]
Quarterly Financial Data (Unaudited)	Quarterly Financial Data (Unaudited) The following is summarized quarterly financial data for fiscal 2017 and 2016 (in thousands, except per share amounts): 2017 First Quarter Second Quarter Third Quarter Fourth Quarter Total Net sales $ 635,019 $ 604,349 $ 618,832 $ 669,852 $ 2,528,052 Gross profit 64,356 63,800 61,185 66,514 255,855 Net income 28,179 29,295 25,579 29,009 112,062 Earnings per share (1): Basic $ 0.84 $ 0.87 $ 0.76 $ 0.86 $ 3.33 Diluted $ 0.82 $ 0.84 $ 0.74 $ 0.84 $ 3.24 2016 First Quarter Second Quarter Third Quarter Fourth Quarter Total Net sales $ 616,664 $ 618,660 $ 667,616 $ 653,064 $ 2,556,004 Gross profit 50,059 53,272 62,498 61,530 227,359 Net income 14,448 16,787 26,099 19,093 76,427 Earnings per share (1): Basic $ 0.43 $ 0.50 $ 0.78 $ 0.57 $ 2.29 Diluted $ 0.42 $ 0.50 $ 0.76 $ 0.56 $ 2.24 (1) The annual total amounts may not equal the sum of the quarterly amounts due to rounding. Earnings per share is computed independently for each quarter.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Sep. 30, 2017
Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	Schedule II – Valuation and Qualifying Accounts For the fiscal years ended September 30, 2017 , October 1, 2016 and October 3, 2015 (in thousands): Descriptions Balance at beginning of period Additions charged to costs and expenses Additions charged to other accounts Deductions Balance at end of period Fiscal Year 2017: Allowance for losses on accounts receivable (deducted from the asset to which it relates) $ 2,368 $ 566 $ — $ (1,954 ) $ 980 Valuation allowance on deferred income tax assets (deducted from the asset to which it relates) $ 41,002 $ 20,678 $ — $ (12 ) $ 61,668 Fiscal Year 2016: Allowance for losses on accounts receivable (deducted from the asset to which it relates) $ 879 $ 1,492 $ — $ (3 ) $ 2,368 Valuation allowance on deferred income tax assets (deducted from the asset to which it relates) $ 58,343 $ 1,121 $ — $ (18,462 ) $ 41,002 Fiscal Year 2015: Allowance for losses on accounts receivable (deducted from the asset to which it relates) $ 1,188 $ 581 $ — $ (890 ) $ 879 Valuation allowance on deferred income tax assets (deducted from the asset to which it relates) $ 41,935 $ 16,408 $ — $ — $ 58,343

Description of Business and S24

Description of Business and Significant Accounting Policies (Policies)	12 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Consolidation Principles	Consolidation Principles and Basis of Presentation: The consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") and include the accounts of Plexus Corp. and its subsidiaries. All intercompany transactions have been eliminated. Certain prior period amounts have been reclassified to conform to the current period presentation. The Company’s fiscal year ends on the Saturday closest to September 30. The Company also uses a "4-4-5" weekly accounting system for the interim periods in each quarter. Each quarter, therefore, ends on a Saturday at the end of the 4-4-5 period. Periodically, an additional week must be added to the fiscal year to re-align with the Saturday closest to September 30. Fiscal 2017 and fiscal 2016 each included 52 weeks; fiscal 2015 included 53 weeks.
Basis of Presentation	Consolidation Principles and Basis of Presentation: The consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") and include the accounts of Plexus Corp. and its subsidiaries. All intercompany transactions have been eliminated. Certain prior period amounts have been reclassified to conform to the current period presentation. The Company’s fiscal year ends on the Saturday closest to September 30. The Company also uses a "4-4-5" weekly accounting system for the interim periods in each quarter. Each quarter, therefore, ends on a Saturday at the end of the 4-4-5 period. Periodically, an additional week must be added to the fiscal year to re-align with the Saturday closest to September 30. Fiscal 2017 and fiscal 2016 each included 52 weeks; fiscal 2015 included 53 weeks.
Cash and Cash Equivalents and Restricted Cash	Cash and Cash Equivalents and Restricted Cash: Cash equivalents include short-term highly liquid investments and are classified as Level 1 in the fair value hierarchy described below. Restricted cash represents cash received from customers to settle invoices sold under accounts receivable purchase agreements that is contractually required to be set aside. The restrictions will lapse when the cash is remitted to the purchaser of the receivables. Restricted cash is also classified as Level 1 in the fair value hierarchy described below.
Inventories	Inventories: Inventories are valued at the lower of cost or market. Cost is determined by the first-in, first-out ("FIFO") method. Valuing inventories at the lower of cost or market requires the use of estimates and judgment. Customers may cancel their orders, change production quantities or delay production for a number of reasons that are beyond the Company’s control. Any of these, or certain additional actions, could impact the valuation of inventory. Any actions taken by the Company’s customers that could impact the value of its inventory are considered when determining the lower of cost or market valuations. In certain instances, in accordance with contractual terms, the Company receives customer deposits to offset obsolete and excess inventory risks.
Property, Plant and Equipment and Depreciation	Property, Plant and Equipment and Depreciation: Property, plant and equipment is stated at cost and depreciated using the straight-line method over the estimated useful lives of the respective assets. Estimated useful lives for major classes of depreciable assets are as follows: Buildings and improvements 5-39 years Machinery and equipment 3-7 years Computer hardware and software 3-10 years Certain facilities and equipment held under capital leases are classified as property, plant and equipment and amortized using the straight-line method over the term of the lease and the related obligations are recorded as liabilities. Amortization of assets held under capital leases is included in depreciation expense (see Note 3, "Property, Plant and Equipment") and the financing component of the lease payments is classified as interest expense. Maintenance and repairs are expensed as incurred. The Company capitalizes significant costs incurred in the acquisition or development of software for internal use. This includes costs of the software, consulting services and compensation costs for employees directly involved in developing internal use computer software.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets: Long-lived assets, including property, plant and equipment and intangible assets with finite lives are reviewed for impairment and written down to fair value when facts and circumstances indicate that the carrying value of long-lived assets or asset groups may not be recoverable through estimated future undiscounted cash flows. If an impairment has occurred, a write-down to estimated fair value is made and the impairment loss is recognized as a charge against current operations. The impairment analysis is based on management’s assumptions, including future revenue and cash flow projections. Circumstances that may lead to impairment of property, plant and equipment and intangible assets with finite lives include reduced expectations for future performance or industry demand and possible further restructurings, among others.
Revenue Recognition	Revenue Recognition: Net sales from manufacturing services are recognized when the product has been shipped, the risk of ownership has transferred to the customer, the price to the buyer is fixed or determinable, and recoverability is reasonably assured. This point depends on contractual terms and generally occurs upon shipment of the goods from Plexus. Generally, there are no formal customer acceptance requirements or further obligations related to manufacturing services; if such requirements or obligations exist, then a sale is recognized at the time when such requirements are completed and such obligations are fulfilled. Net sales also include amounts billed to customers for shipping and handling. The corresponding shipping and handling costs are included in cost of sales. Net sales from engineering design and development services, which are generally performed under contracts with a duration of twelve months or less, are typically recognized as program costs are incurred by utilizing the proportional performance model. The completed performance model is used if certain customer acceptance criteria exist. Any losses are recognized when anticipated. Net sales from engineering design and development services were less than 5.0% of consolidated net sales for each of fiscal 2017 , 2016 and 2015 .
Income Taxes	Income Taxes: Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The Company does not currently provide for additional U.S. and foreign income taxes that would become payable upon the repatriation of undistributed earnings. The Company maintains valuation allowances when it is more likely than not that all or a portion of a deferred tax asset will not be realized. In determining whether a valuation allowance is required, the Company takes into account such factors as prior earnings history, expected future earnings, carryback and carryforward periods, and tax strategies that could potentially enhance the likelihood of the realization of a deferred tax asset.
Foreign Currency Translation and Transactions	Foreign Currency Translation & Transactions: The Company translates assets and liabilities of subsidiaries operating outside of the U.S. with a functional currency other than the U.S. dollar into U.S. dollars using exchange rates in effect at the relevant balance sheet date and net sales, expenses and cash flows at the average exchange rates during the respective periods. Adjustments resulting from translation of the financial statements are recorded as a component of "Accumulated other comprehensive loss." Exchange gains and losses arising from transactions denominated in a currency other than the functional currency of the entity involved and remeasurement adjustments for foreign operations where the U.S. dollar is the functional currency are included in the Consolidated Statements of Comprehensive Income as a component of "Miscellaneous income (expense)." Exchange gains (losses) on foreign currency transactions were $2.3 million , $(1.7) million , and $1.3 million for fiscal 2017 , 2016 and 2015 , respectively. These amounts include the amount of gain (loss) recognized in income during each fiscal year due to forward currency exchange contracts entered into to hedge recognized assets or liabilities ("non-designated hedges") the Company entered into during each respective year. Refer to Note 5, "Derivatives and Fair Value Measurements," for further details on derivatives.
Derivatives	Derivatives: All derivatives are recognized on the balance sheets at fair value. The Company periodically enters into forward currency exchange contracts and interest rate swaps. On the date a derivative contract is entered into, the Company designates the derivative as a non-designated hedge or a hedge of a forecasted transaction or of the variability of cash flows to be received or paid related to a recognized asset or liability (a "cash flow" hedge). The Company does not enter into derivatives for speculative purposes. Changes in the fair value of non-designated derivatives are recorded in earnings as are the gains or losses related to the hedged asset or liability. Changes in the fair value of a derivative that qualifies as a cash flow hedge are recorded in "Accumulated other comprehensive loss" within shareholders’ equity, until earnings are affected by the variability of cash flows. Certain forward currency exchange contracts are treated as cash flow hedges and, therefore, $2.4 million , $9.0 million and $(11.2) million was recorded in "Accumulated other comprehensive loss" for fiscal 2017 , 2016 and 2015 , respectively. See Note 5, "Derivatives and Fair Value Measurements," for further information.
Grants from Government Authorities	Grants from Government Authorities: Grants from governments are recognized at their fair value where there is reasonable assurance that the grant funds will be received and the Company will comply with all attached conditions to the grant. Government grants relating to property, plant and equipment are recorded as an offset to the carrying value of the related assets at the time of capitalization. Government grants relating to other costs incurred are recognized as an offset to those related costs, for which the grants are intended to compensate for, at the time they are recognized.
Earnings Per Share	Earnings Per Share: The computation of basic earnings per common share is based upon the weighted average number of common shares outstanding and net income. The computation of diluted earnings per common share reflects additional dilution from share-based awards, excluding any with an antidilutive effect. See Note 7, "Earnings Per Share," for further information.
Share-based Compensation	Share-based Compensation: The Company measures all grants of share-based payments to employees, including grants of employee stock options, at fair value and expenses them in the Consolidated Statements of Comprehensive Income over the service period (generally the vesting period) of the grant. See Note 9, "Benefit Plans," for further information.
Comprehensive Income (Loss)	Comprehensive Income (Loss): The Company follows the established standards for reporting comprehensive income (loss), which is defined as the changes in equity of an enterprise except those resulting from shareholder transactions.
Use of Estimates	Use of Estimates: The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.
Fair Value of Financial Instruments	Fair Value of Financial Instruments: The Company holds financial instruments consisting of cash and cash equivalents, restricted cash, accounts receivable, certain deferred compensation assets held under trust arrangements, accounts payable, debt, derivatives, and capital lease obligations. The carrying values of cash and cash equivalents, restricted cash, accounts receivable, accounts payable, and capital lease obligations as reported in the consolidated financial statements approximate fair value. Derivatives and certain deferred compensation assets held under trust arrangements are recorded at fair value. Accounts receivable are reflected at net realizable value based on anticipated losses due to potentially uncollectible balances. Anticipated losses are based on management’s analysis of historical losses and changes in customers’ credit status. The fair value of the Company’s debt was $284.5 million and $251.4 million as of September 30, 2017 and October 1, 2016 , respectively. The carrying value of the Company's debt was $283.0 million and $250.0 million as of September 30, 2017 and October 1, 2016 , respectively. The Company uses quoted market prices when available or discounted cash flows to calculate fair value. If measured at fair value in the financial statements, long-term debt (including the current portion) would be classified as Level 2 in the fair value hierarchy described below. The fair values of the Company’s derivatives are disclosed in Note 5, "Derivatives and Fair Value Measurements." The fair values of the deferred compensation assets held under trust arrangements are discussed in Note 9, "Benefit Plans." Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (or exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The accounting guidance establishes a fair value hierarchy based on three levels of inputs that may be used to measure fair value. The input levels are: Level 1: Quoted (observable) market prices in active markets for identical assets or liabilities. Level 2: Inputs other than Level 1 that are observable, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability. Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the asset or liability.
Business and Credit Concentrations	Business and Credit Concentrations: Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash, cash equivalents, trade accounts receivable and derivative instruments, specifically related to counterparties. In accordance with the Company’s investment policy, the Company’s cash, cash equivalents and derivative instruments were placed with recognized financial institutions. The Company’s investment policy limits the amount of credit exposure in any one issue and the maturity date of the investment securities that typically comprise investment grade short-term debt instruments. Concentrations of credit risk in accounts receivable resulting from sales to major customers are discussed in Note 11, "Reportable Segments, Geographic Information and Major Customers". The Company, at times, requires cash deposits for services performed. The Company also closely monitors extensions of credit.
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements: In November 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-18 to address the classifications and presentation of changes in restricted cash in the statement of cash flows. The Company adopted this guidance retrospectively during the first quarter of fiscal 2017 and, as a result, the Company has included restricted cash within the Consolidated Statements of Cash Flows; such amounts were not material. The retrospective adoption did not impact the prior period Consolidated Statements of Cash Flows since there was no restricted cash during any of the prior periods presented. Amounts included in restricted cash represent cash received from customers to settle invoices sold under the trade accounts receivable sale programs that is contractually required to be set aside. The restrictions will lapse when the cash is remitted to the purchaser of the receivables. In March 2016, the FASB issued ASU 2016-09, which changes the accounting for certain aspects of share-based payments to employees. The guidance requires the recognition of the income tax effects of awards in the income statement when the awards vest or are settled, thus eliminating additional paid-in capital pools. The guidance also allows for the employer to repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting. In addition, the guidance allows for a policy election to account for forfeitures as they occur rather than on an estimated basis. The Company adopted this guidance prospectively during the first fiscal quarter of 2017. Upon adoption, the Company recognized no net impact to its fiscal 2017 opening retained earnings balance as an incremental $4.9 million net operating loss carryforward related to tax deductions in excess of compensation expense for stock options was fully offset by an increase to the valuation allowance. The adoption did not have any other material impacts and will not materially impact the Company's future financial statements as long as the Company remains in a valuation allowance in the jurisdictions in which share-based compensation awards and options vest and are exercised, respectively. Recently Issued Accounting Pronouncements Not Yet Adopted: In August 2017, the FASB issued ASU 2017-12 related to the accounting for hedging activities. The pronouncement expands and refines hedge accounting, aligns the recognition and presentation of the effects of hedging instruments and hedge items in the financial statements, and includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. This guidance is effective for the Company beginning in the first quarter of fiscal year 2020 and early adoption is permitted. The Company is finalizing its assessment of the impact of the guidance, but does not believe it will have a material impact on the Company's Consolidated Financial Statements. In October 2016, the FASB issued ASU 2016-16 related to the income tax consequences of intra-entity transfers of assets other than inventory. The new standard eliminates the exception for an intra-entity transfer of an asset other than inventory and requires an entity to recognize the income tax consequences when the transfer occurs. This guidance is effective for the Company beginning in the first quarter of fiscal year 2019 and early adoption is permitted. This guidance should be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The Company is currently assessing the impact this new standard may have on its Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15 related to the classification of certain cash receipts and cash payments, which clarifies how entities should classify certain cash receipts and cash payments on the statement of cash flows. The new standard addresses certain issues where diversity in practice was identified. It also amends existing guidance, which is principles based and often requires judgment to determine the appropriate classification of cash flows as operating, investing or financing activities and clarifies how the predominance principle should be applied when cash receipts and cash payments have aspects of more than one class of cash flows. This guidance is effective for the Company beginning in the first quarter of fiscal year 2019, and will generally require retrospective adoption. Early adoption is permitted. The Company is currently assessing the impact this new standard may have on its Consolidated Statements of Cash Flows. In February 2016, the FASB issued ASU 2016-02, which requires lessees to recognize most leases on their balance sheets but record expenses on their income statements in a manner similar to current accounting. For lessors, the guidance modifies the classification criteria and the accounting for sales-type and direct financing leases. The guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. Early adoption is permitted. The Company is currently in the process of assessing the impact of the adoption of the new standard on its Consolidated Financial Statements and the timing of adoption. In May 2014, the FASB issued ASU 2014-09, which requires an entity to recognize revenue relating to contracts with customers that depicts the transfer of promised goods or services to customers in an amount reflecting the consideration to which the entity expects to be entitled in exchange for such goods or services ("Topic 606"). Topic 606 also requires disclosures enabling users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers and is effective for the Company beginning in the first quarter of fiscal year 2019. The Company developed a comprehensive project plan that includes a global cross-functional team of representatives to conduct an assessment of Topic 606 and its potential impacts on the Company. The project plan includes analyzing the standard’s impact on the Company’s various revenue streams, comparing its historical accounting policies and practices to the requirements of the new standard, and identifying potential differences from applying the requirements of the new standard to its contracts. The Company is in the process of identifying and implementing appropriate changes to its current accounting policies, business processes, systems and controls to support revenue recognition and disclosures under Topic 606. As of September 30, 2017 , the Company has determined that the new standard will result in a change to the timing of revenue recognition for a significant portion of the Company's revenue, whereby revenue will be recognized "over time," as products are produced, as opposed to at a "point in time" upon physical delivery. The new standard could have a material impact on the Company's consolidated financial statements upon initial adoption, primarily as the Company recognizes an increase in contract assets for unbilled receivables with a corresponding reduction in finished goods and work-in-process inventory. The Company presently expects to adopt Topic 606 at the beginning of fiscal 2019 using the modified retrospective approach. The Company believes that no other recently issued accounting standards will have a material impact on its Consolidated Financial Statements, or apply to its operations.

Description of Business and S25

Description of Business and Significant Accounting Policies (Tables)	12 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Schedule of Cash and Cash Equivalents	As of September 30, 2017 and October 1, 2016 , cash and cash equivalents and restricted cash consisted of the following (in thousands): 2017 2016 Cash $ 264,222 $ 175,396 Money market funds and other 304,638 257,568 Restricted cash 394 — Total cash and cash equivalents and restricted cash $ 569,254 $ 432,964
Schedule of Restricted Cash and Cash Equivalents	As of September 30, 2017 and October 1, 2016 , cash and cash equivalents and restricted cash consisted of the following (in thousands): 2017 2016 Cash $ 264,222 $ 175,396 Money market funds and other 304,638 257,568 Restricted cash 394 — Total cash and cash equivalents and restricted cash $ 569,254 $ 432,964
Schedule of Property, Plant and Equipment	Estimated useful lives for major classes of depreciable assets are as follows: Buildings and improvements 5-39 years Machinery and equipment 3-7 years Computer hardware and software 3-10 years Property, plant and equipment as of September 30, 2017 and October 1, 2016 consisted of the following (in thousands): 2017 2016 Land, buildings and improvements $ 262,428 $ 247,806 Machinery and equipment 348,593 336,378 Computer hardware and software 117,404 107,239 Construction in progress 12,790 4,298 Total property, plant and equipment, gross 741,215 695,721 Less: accumulated depreciation (426,550 ) (404,496 ) Total property, plant and equipment, net $ 314,665 $ 291,225
Schedule of Accumulated Other Comprehensive Loss	Accumulated other comprehensive loss consists of the following as of September 30, 2017 and October 1, 2016 (in thousands): 2017 2016 Foreign currency translation adjustments $ (7,482 ) $ (11,637 ) Cumulative change in fair value of derivative instruments 2,503 98 Accumulated other comprehensive loss $ (4,979 ) $ (11,539 )

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Sep. 30, 2017
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories as of September 30, 2017 and October 1, 2016 consisted of the following (in thousands): 2017 2016 Raw materials $ 477,921 $ 414,303 Work-in-process 86,367 69,423 Finished goods 90,354 80,405 Total inventories $ 654,642 $ 564,131

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Sep. 30, 2017
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Estimated useful lives for major classes of depreciable assets are as follows: Buildings and improvements 5-39 years Machinery and equipment 3-7 years Computer hardware and software 3-10 years Property, plant and equipment as of September 30, 2017 and October 1, 2016 consisted of the following (in thousands): 2017 2016 Land, buildings and improvements $ 262,428 $ 247,806 Machinery and equipment 348,593 336,378 Computer hardware and software 117,404 107,239 Construction in progress 12,790 4,298 Total property, plant and equipment, gross 741,215 695,721 Less: accumulated depreciation (426,550 ) (404,496 ) Total property, plant and equipment, net $ 314,665 $ 291,225
Schedule of Assets Held Under Capital Leases and Included in Property, Plant and Equipment	Assets held under capital leases and included in property, plant and equipment as of September 30, 2017 and October 1, 2016 consisted of the following (in thousands): 2017 2016 Buildings and improvements $ 23,717 $ 12,801 Machinery and equipment 11,070 6,070 Total property, plant and equipment held under capital leases, gross 34,787 18,871 Less: accumulated amortization (6,465 ) (8,042 ) Total property, plant and equipment held under capital leases, net $ 28,322 $ 10,829

Debt, Capital Lease Obligatio28

Debt, Capital Lease Obligations and Other Financing (Tables)	12 Months Ended
	Sep. 30, 2017
Debt and Capital Lease Obligations [Abstract]
Schedule of Debt and Capital Lease Obligations	Debt and capital lease obligations as of September 30, 2017 and October 1, 2016 , consisted of the following (in thousands): 2017 2016 Borrowings under the credit facility $ 108,000 $ 75,000 5.20% Senior notes, due June 15, 2018 175,000 175,000 Capital lease and other financing obligations 30,901 13,614 Unamortized deferred financing fees (794 ) (1,105 ) Total obligations 313,107 262,509 Less: current portion (286,934 ) (78,507 ) Long-term debt and capital lease obligations, net of current portion $ 26,173 $ 184,002
Schedule of Aggregate Scheduled Maturities of Debt Obligations	The aggregate scheduled maturities of the Company’s debt obligations as of September 30, 2017 , are as follows (in thousands): 2018 $ 283,000 2019 — 2020 — 2021 — 2022 — Thereafter — Total $ 283,000
Schedule of Aggregate Scheduled Maturities of Obligations Under Capital Leases	The aggregate scheduled maturities of the Company’s capital leases and other financing obligations as of September 30, 2017 , are as follows (in thousands): 2018 $ 3,934 2019 2,705 2020 1,648 2021 820 2022 651 Thereafter 21,143 Total $ 30,901 The future minimum payments under the remainder of the ten -year base lease agreement, as well as the two five -year renewal options, are as follows (in thousands): 2018 $ 1,513 2019 1,550 2020 1,589 2021 1,629 2022 1,670 2023 through 2024 (remainder of the ten-year base lease agreement) 3,466 $ 11,417 2025 through 2029 (first five-year renewal option) 9,451 2030 through 2034 (second five-year renewal option) 10,870 Total $ 31,738

Derivatives and Fair Value Me29

Derivatives and Fair Value Measurements (Tables)	12 Months Ended
	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Fair Values of Derivative Instruments	The tables below present information regarding the fair values of derivative instruments (as defined in Note 1, "Description of Business and Significant Accounting Policies") and the effects of derivative instruments on the Company’s Consolidated Financial Statements: Fair Values of Derivative Instruments In thousands of dollars Asset Derivatives Liability Derivatives September 30, October 1, September 30, October 1, Derivatives designated as hedging instruments Balance Sheet Classification Fair Value Fair Value Balance Sheet Classification Fair Value Fair Value Interest rate swaps Prepaid expenses and other $ — $ — Other accrued liabilities $ — $ 132 Forward currency forward contracts Prepaid expenses and other $ 2,024 $ — Other accrued liabilities $ — $ 486 Fair Values of Derivative Instruments In thousands of dollars Asset Derivatives Liability Derivatives September 30, October 1, September 30, October 1, Derivatives not designated as hedging instruments Balance Sheet Classification Fair Value Fair Value Balance Sheet Classification Fair Value Fair Value Forward currency forward contracts Prepaid expenses and other $ 35 $ 182 Other accrued liabilities $ 118 $ 130
Schedule of Derivative Impact on Accumulated Other Comprehensive Income (Loss)	Derivative Impact on Accumulated Other Comprehensive Loss ("OCL") for the Twelve Months Ended In thousands of dollars Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion) September 30, 2017 October 1, 2016 October 3, 2015 Interest rate swaps $ (10 ) $ (16 ) $ (1,258 ) Forward currency forward contracts $ (848 ) $ 5,311 $ (15,660 )
Schedule of Derivative Impact on Gain (Loss) Recognized in Income	Derivative Impact on Gain (Loss) Recognized in Income for the Twelve Months Ended In thousands of dollars Derivatives in Cash Flow Hedging Relationships Classification of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion) September 30, 2017 October 1, 2016 October 3, 2015 Interest rate swaps Interest expense $ (142 ) $ (381 ) $ (579 ) Forward currency forward contracts Selling and administrative expenses $ (317 ) $ (350 ) $ (597 ) Forward currency forward contracts Cost of sales $ (3,041 ) $ (3,261 ) $ (4,843 ) Treasury Rate Locks Interest expense $ 321 $ 320 $ 324 Interest rate swaps Income tax expense $ (84 ) $ — $ —
Schedule of Amount of Gain (Loss) on Derivatives Recognized in Income	Derivatives Not Designated as Hedging Instruments Location of Gain Recognized on Derivatives in Income Amount of Gain on Derivatives Recognized in Income September 30, 2017 October 1, 2016 October 3, 2015 Forward currency forward contracts Miscellaneous income (expense) $ 2,153 $ 121 $ 164
Schedule of Derivatives Fair Value Measurements Using Input Levels	The following table lists the fair values of liabilities of the Company’s derivatives as of September 30, 2017 and October 1, 2016 , by input level as defined in Note 1, "Description of Business and Significant Accounting Policies": Fair Value Measurements Using Input Levels Asset/(Liability) In thousands of dollars Fiscal year ended September 30, 2017 Level 1 Level 2 Level 3 Total Derivatives Forward currency forward contracts $ — $ 1,941 $ — $ 1,941 Fiscal year ended October 1, 2016 Derivatives Interest rate swaps $ — $ (132 ) $ — $ (132 ) Forward currency forward contracts $ — $ (434 ) $ — $ (434 )

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Schedule of Domestic and Foreign Components of Income (Loss) Before Income Taxes	The domestic and foreign components of income (loss) before income tax expense for fiscal 2017 , 2016 and 2015 were as follows (in thousands): 2017 2016 2015 U.S. $ (35,209 ) $ (26,796 ) $ (32,480 ) Foreign 157,032 114,190 138,775 $ 121,823 $ 87,394 $ 106,295
Schedule of Income Tax Expense (Benefit)	Income tax expense (benefit) for fiscal 2017 , 2016 and 2015 were as follows (in thousands): 2017 2016 2015 Current: Federal $ 78 $ — $ — State 33 (15 ) (397 ) Foreign 10,016 11,312 12,957 10,127 11,297 12,560 Deferred: Federal 77 — — State 38 24 (399 ) Foreign (481 ) (354 ) (198 ) (366 ) (330 ) (597 ) $ 9,761 $ 10,967 $ 11,963
Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax Rates	The following is a reconciliation of the federal statutory income tax rate to the effective income tax rates reflected in the Consolidated Statements of Comprehensive Income for fiscal 2017 , 2016 and 2015 : 2017 2016 2015 Federal statutory income tax rate 35.0 % 35.0 % 35.0 % Increase (decrease) resulting from: Permanent differences 1.2 1.6 1.3 Foreign tax rate differences (39.9 ) (36.3 ) (38.0 ) Disregarded entity benefit (0.9 ) (1.8 ) (1.2 ) Dividend repatriation — 32.9 — Valuation allowances 12.2 (18.7 ) 16.5 Other, net 0.4 (0.1 ) (2.3 ) Effective income tax rate 8.0 % 12.6 % 11.3 %
Schedule of Components of Net Deferred Income Tax Asset	The components of the net deferred income tax assets as of September 30, 2017 and October 1, 2016 , were as follows (in thousands): 2017 2016 Deferred income tax assets: Loss/credit carryforwards $ 44,831 $ 24,017 Inventories 7,710 7,527 Accrued benefits 25,811 25,493 Allowance for bad debts 319 461 Other 2,732 2,822 Total gross deferred income tax assets 81,403 60,320 Less valuation allowances (61,668 ) (41,002 ) Deferred income tax assets 19,735 19,318 Deferred income tax liabilities: Property, plant and equipment 14,443 14,400 Other — 84 Deferred income tax liabilities 14,443 14,484 Net deferred income tax assets $ 5,292 $ 4,834
Schedule of Reconciliation of Beginning And Ending Amounts of Unrecognized Income Tax Benefits	The following is a reconciliation of the beginning and ending amounts of unrecognized income tax benefits (in thousands): 2017 2016 2015 Balance at beginning of fiscal year $ 2,799 $ 2,353 $ 2,368 Gross increases for tax positions of prior years 184 534 73 Gross increases for tax positions of the current year 163 — — Gross decreases for tax positions of prior years (31 ) (88 ) (88 ) Balance at end of fiscal year $ 3,115 $ 2,799 $ 2,353
Schedule of Years That Remain Subject to Examination by Major Tax Jurisdictions	The Company files income tax returns, including returns for its subsidiaries, with federal, state, local and foreign taxing jurisdictions. The following tax years remain subject to examination by the respective major tax jurisdictions: Jurisdiction Fiscal Years China 2012-2017 Germany 2013-2017 Mexico 2012-2017 Romania 2011-2017 United Kingdom 2014-2017 United States Federal 2011, 2013-2017 State 2003-2017

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Reconciliation of Amounts Utilized in Computation of Basic and Diluted Earnings Per Share	The following is a reconciliation of the amounts utilized in the computation of basic and diluted earnings per share for fiscal 2017 , 2016 and 2015 (in thousands, except per share amounts): 2017 2016 2015 Net income $ 112,062 $ 76,427 $ 94,332 Basic weighted average common shares outstanding 33,612 33,374 33,618 Dilutive effect of share-based awards outstanding 941 724 761 Diluted weighted average shares outstanding 34,553 34,098 34,379 Earnings per share: Basic $ 3.33 $ 2.29 $ 2.81 Diluted $ 3.24 $ 2.24 $ 2.74

Operating Lease Commitments (T

Operating Lease Commitments (Tables)	12 Months Ended
	Sep. 30, 2017
Leases, Operating [Abstract]
Schedule of Future Minimum Annual Payments on Operating Leases	Future minimum annual payments on operating leases are as follows (in thousands): 2018 $ 9,390 2019 8,191 2020 7,873 2021 4,279 2022 1,718 Thereafter 5,106 Total future minimum operating lease payments $ 36,557

Benefit Plans (Tables)

Benefit Plans (Tables)	12 Months Ended
	Sep. 30, 2017
Compensation Related Costs [Abstract]
Schedule of Stock Option and SARs Activity	A summary of the Company’s stock option and SAR activity follows: Number of Options/SARs (in thousands) Weighted Average Exercise Price Aggregate Intrinsic Value (in thousands) Outstanding as of September 27, 2014 2,270 $ 31.65 Granted 221 39.53 Canceled (25 ) 36.50 Exercised (549 ) 28.93 Outstanding as of October 3, 2015 1,917 $ 33.27 Granted 229 39.52 Canceled (66 ) 41.48 Exercised (619 ) 31.59 Outstanding as of October 1, 2016 1,461 $ 34.59 Granted 36 45.45 Canceled (4 ) 30.88 Exercised (521 ) 32.29 Outstanding as of September 30, 2017 972 $ 36.23 $ 19,283 Number of Options/SARs (in thousands) Weighted Average Exercise Price Weighted Average Remaining Life (years) Aggregate Intrinsic Value (in thousands) Exercisable as of: October 3, 2015 1,560 $ 31.67 October 1, 2016 1,125 $ 33.11 September 30, 2017 865 $ 35.62 4.21 $ 17,692
Schedule of Stock Option and SARs Information	The following table summarizes outstanding stock option and SAR information as of September 30, 2017 (Options/SARs in thousands): Range of Exercise Prices Number of Options/SARs Outstanding (in thousands) Weighted Average Exercise Price Weighted Average Remaining Life (years) Number of Options / SARs Exercisable (in thousands) Weighted Average Exercise Price $14.17 - $31.70 244 $ 26.27 3.40 244 $ 26.27 $31.71 - $37.12 279 $ 35.56 5.00 243 $ 35.72 $37.13 - $41.84 270 $ 40.11 4.92 252 $ 39.99 $41.85 - $45.45 179 $ 44.99 5.68 126 $ 44.81 $14.17 - $45.45 972 $ 36.23 4.70 865 $ 35.62
Schedule of Estimated Option and SAR Grants Using Black-Scholes Pricing Model	The fair value of each option and SAR grant was estimated at the date of grant using the Black-Scholes option-pricing model based on the assumption ranges below: 2017 2016 2015 Expected life (years) 5.70 5.70 4.50 - 5.70 Risk-free interest rate 1.50% 1.23 - 1.87% 1.52 - 1.64% Expected volatility 34% 35 - 37% 37 - 38% Dividend yield — — —
Schedule of PSU and RSU Activity	A summary of the Company’s PSU and RSU activity follows: Number of Shares (in thousands) Weighted Average Fair Value at Date of Grant Aggregate Intrinsic Value (in thousands) Units outstanding as of September 27, 2014 730 $ 31.97 Granted 325 41.46 Canceled (43 ) 35.15 Vested (216 ) 37.52 Units outstanding as of October 3, 2015 796 $ 38.18 Granted 499 39.68 Canceled (29 ) 36.84 Vested (244 ) 27.77 Units outstanding as of October 1, 2016 1,022 $ 41.49 Granted 397 54.21 Canceled (22 ) 41.17 Vested (329 ) 43.76 Units outstanding as of September 30, 2017 1,068 $ 45.97 $ 59,905

Reportable Segments, Geograph34

Reportable Segments, Geographic Information and Major Customers (Tables)	12 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Schedule of Reportable Segments Information	Information about the Company’s three reportable segments for fiscal 2017 , 2016 and 2015 is as follows (in thousands): 2017 2016 2015 Net sales: AMER $ 1,166,346 $ 1,328,760 $ 1,389,017 APAC 1,279,261 1,161,851 1,285,905 EMEA 192,829 170,450 140,292 Elimination of inter-segment sales (110,384 ) (105,057 ) (160,924 ) $ 2,528,052 $ 2,556,004 $ 2,654,290 Operating income (loss): AMER $ 41,924 $ 64,921 $ 68,585 APAC 200,103 155,501 160,217 EMEA (6,197 ) (3,746 ) (8,129 ) Corporate and other costs (105,922 ) (117,237 ) (105,237 ) $ 129,908 $ 99,439 $ 115,436 Other income (expense): Interest expense (13,578 ) (14,635 ) (13,964 ) Interest income 5,042 4,242 3,499 Miscellaneous 451 (1,652 ) 1,324 Income before income taxes $ 121,823 $ 87,394 $ 106,295 Depreciation: AMER $ 19,694 $ 19,937 $ 17,753 APAC 15,588 16,874 18,176 EMEA 5,467 6,106 8,339 Corporate 4,581 4,497 4,110 $ 45,330 $ 47,414 $ 48,378 Capital expenditures: AMER $ 18,111 $ 14,389 $ 17,595 APAC 13,816 10,786 9,590 EMEA 5,748 3,399 6,976 Corporate 863 2,549 915 $ 38,538 $ 31,123 $ 35,076 September 30, October 1, Total assets: AMER $ 595,851 $ 590,850 APAC 1,163,111 1,009,917 EMEA 172,830 136,636 Corporate and eliminations 44,390 28,416 $ 1,976,182 $ 1,765,819
Schedule of Net Sales and Long-lived Assets	The following information is provided in accordance with the required segment disclosures for fiscal 2017 , 2016 and 2015 . Net sales were based on the Company’s location providing the product or service (in thousands): 2017 2016 2015 Net sales: United States $ 984,773 $ 1,134,342 $ 1,303,106 Malaysia 940,045 844,501 926,059 China 339,216 317,350 359,846 Mexico 181,573 194,418 85,911 Romania 114,363 83,712 65,338 United Kingdom 70,163 81,894 70,335 Germany 8,303 4,844 4,619 Elimination of inter-segment sales (110,384 ) (105,057 ) (160,924 ) $ 2,528,052 $ 2,556,004 $ 2,654,290 September 30, October 1, Long-lived assets: United States $ 110,828 $ 92,152 Malaysia 74,769 71,596 Mexico 37,237 39,155 Romania 33,717 30,408 China 18,602 19,197 United Kingdom 6,456 6,594 Germany 303 307 Other Foreign 5,126 4,940 Corporate 27,627 26,876 $ 314,665 $ 291,225
Concentration of Risk	As a percentage of consolidated net sales, net sales attributable to customers representing 10.0% or more of consolidated net sales for fiscal 2017 , 2016 and 2015 were as follows: 2017 2016 2015 General Electric Company ("GE") 12.2% 11.1% 10.6% Micron Technology, Inc. ("Micron") * 10.4% * ARRIS Group, Inc. ("Arris") * 10.1% 12.6% * Net sales attributable to the customer were less than 10.0% of consolidated net sales for the period.

Guarantees (Tables)

Guarantees (Tables)	12 Months Ended
	Sep. 30, 2017
Guarantees [Abstract]
Schedule of Activity Related to Limited Warranty Liability	Below is a table summarizing the activity related to the Company’s limited warranty liability for fiscal 2017 , 2016 and 2015 (in thousands): Limited warranty liability, as of September 27, 2014 6,803 Accruals for warranties issued during the period 1,742 Settlements (in cash or in kind) during the period (2,698 ) Limited warranty liability, as of October 3, 2015 5,847 Accruals for warranties issued during the period 1,777 Settlements (in cash or in kind) during the period (1,515 ) Limited warranty liability, as of October 1, 2016 6,109 Accruals for warranties issued during the period 912 Settlements (in cash or in kind) during the period (2,265 ) Limited warranty liability, as of September 30, 2017 4,756

Restructuring and Other Charg36

Restructuring and Other Charges (Tables)	12 Months Ended
	Sep. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring Accrual Activity	The Company's restructuring accrual activity for the years ended September 30, 2017 , October 1, 2016 and October 3, 2015 is included in the table below (in thousands): Employee Termination and Severance Costs Lease Obligations and Other Exit Costs Total Accrual balance, September 27, 2014 $ 142 $ — $ 142 Restructuring and other charges 144 1,547 1,691 Amounts utilized (286 ) (1,547 ) (1,833 ) Accrual balance, October 3, 2015 $ — $ — $ — Restructuring and other charges 5,255 1,779 7,034 Amounts utilized (4,571 ) (1,621 ) (6,192 ) Accrual balance, October 1, 2016 $ 684 $ 158 $ 842 Restructuring and other charges — — — Amounts utilized (684 ) (158 ) (842 ) Accrual balance, September 30, 2017 $ — $ — $ —

Quarterly Financial Data (Una37

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Sep. 30, 2017
Quarterly Financial Data [Abstract]
Schedule of Quarterly Financial Data	The following is summarized quarterly financial data for fiscal 2017 and 2016 (in thousands, except per share amounts): 2017 First Quarter Second Quarter Third Quarter Fourth Quarter Total Net sales $ 635,019 $ 604,349 $ 618,832 $ 669,852 $ 2,528,052 Gross profit 64,356 63,800 61,185 66,514 255,855 Net income 28,179 29,295 25,579 29,009 112,062 Earnings per share (1): Basic $ 0.84 $ 0.87 $ 0.76 $ 0.86 $ 3.33 Diluted $ 0.82 $ 0.84 $ 0.74 $ 0.84 $ 3.24 2016 First Quarter Second Quarter Third Quarter Fourth Quarter Total Net sales $ 616,664 $ 618,660 $ 667,616 $ 653,064 $ 2,556,004 Gross profit 50,059 53,272 62,498 61,530 227,359 Net income 14,448 16,787 26,099 19,093 76,427 Earnings per share (1): Basic $ 0.43 $ 0.50 $ 0.78 $ 0.57 $ 2.29 Diluted $ 0.42 $ 0.50 $ 0.76 $ 0.56 $ 2.24 (1) The annual total amounts may not equal the sum of the quarterly amounts due to rounding. Earnings per share is computed independently for each quarter.

Description of Business and S38

Description of Business and Significant Accounting Policies - Schedule of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015	Sep. 27, 2014
Accounting Policies [Abstract]
Cash	$ 264,222	$ 175,396
Money market funds and other	304,638	257,568
Restricted cash	394	0
Total cash and cash equivalents and restricted cash	$ 569,254	$ 432,964	$ 357,106	$ 346,591

Description of Business and S39

Description of Business and Significant Accounting Policies - Schedule of Property, Plant And Equipment, Useful Lives (Details)	12 Months Ended
	Sep. 30, 2017
Buildings and improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Buildings and improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	39 years
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years
Computer hardware and software | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Computer hardware and software | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	10 years

Description of Business and S40

Description of Business and Significant Accounting Policies - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Disaggregation of Revenue [Line Items]
Exchange gains (losses) on foreign currency transactions	$ 2,300,000	$ (1,700,000)	$ 1,300,000
Forward currency exchange contracts treated as cash flow hedges and recorded in accumulated other comprehensive loss	2,405,000	8,967,000	$ (11,223,000)
Fair value of debt	284,500,000	251,400,000
Carrying value of debt	283,000,000	$ 250,000,000
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net impact to fiscal 2017 opening retained earnings balance	$ 0
Engineering Design and Development Services
Disaggregation of Revenue [Line Items]
Percentage of consolidated net sales (less than)	5.00%	5.00%	5.00%
Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net operating loss carryforward related to tax deductions in excess of compensation expense for stock options		$ 4,900,000
Increase to valuation allowance		4,900,000
Accounting Standards Update 2016-09 | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net impact to fiscal 2017 opening retained earnings balance		$ 0

Description of Business and S41

Description of Business and Significant Accounting Policies - Schedule of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Accounting Policies [Abstract]
Foreign currency translation adjustments	$ (7,482)	$ (11,637)
Cumulative change in fair value of derivative instruments	2,503	98
Accumulated other comprehensive loss	$ (4,979)	$ (11,539)

Inventories - Schedule of Inve

Inventories - Schedule of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Inventory Disclosure [Abstract]
Raw materials	$ 477,921	$ 414,303
Work-in-process	86,367	69,423
Finished goods	90,354	80,405
Total inventories	$ 654,642	$ 564,131

Inventories - Narrative (Detai

Inventories - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Inventory [Line Items]
Customer deposits	$ 107,837	$ 84,637
Inventory
Inventory [Line Items]
Customer deposits	$ 106,200	$ 74,600

Property, Plant and Equipment

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 741,215	$ 695,721
Less: accumulated depreciation	(426,550)	(404,496)
Total property, plant and equipment, net	314,665	291,225
Land, buildings and improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	262,428	247,806
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	348,593	336,378
Computer hardware and software
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	117,404	107,239
Construction in progress
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 12,790	$ 4,298

Property, Plant and Equipment45

Property, Plant and Equipment - Assets Held Under Capital Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Capital Leased Assets [Line Items]
Total property, plant and equipment held under capital leases, gross	$ 34,787	$ 18,871
Less: accumulated amortization	(6,465)	(8,042)
Total property, plant and equipment held under capital leases, net	28,322	10,829
Buildings and improvements
Capital Leased Assets [Line Items]
Total property, plant and equipment held under capital leases, gross	23,717	12,801
Machinery and equipment
Capital Leased Assets [Line Items]
Total property, plant and equipment held under capital leases, gross	$ 11,070	$ 6,070

Property, Plant and Equipment46

Property, Plant and Equipment - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Capital Leased Assets [Line Items]
Leased property, plant and equipment capitalized	$ 34,787	$ 18,871
Amortization of assets held under capital leases	3,000	1,900	$ 500
Capital lease additions	20,500	2,900	1,200
Purchase of property, plant and equipment included in accounts payable	10,800	$ 3,500	$ 2,700
Neenah Design Center
Capital Leased Assets [Line Items]
Leased property, plant and equipment capitalized	$ 15,700

Debt, Capital Lease Obligatio47

Debt, Capital Lease Obligations and Other Financing - Schedule of Debt and Capital Lease Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2017	May 05, 2017	Oct. 01, 2016
Debt Instrument [Line Items]
Long-term debt, gross	$ 283,000		$ 250,000
Capital lease and other financing obligations	30,901		13,614
Unamortized deferred financing fees	(794)		(1,105)
Total obligations	313,107		262,509
Less: current portion	(286,934)		(78,507)
Long-term debt and capital lease obligations, net of current portion	26,173		184,002
Line of Credit | Borrowings under the credit facility
Debt Instrument [Line Items]
Long-term debt, gross	108,000	$ 75,000	75,000
Senior Notes | 5.20% Senior notes, due June 15, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 175,000		$ 175,000
Interest rate	5.20%

Debt, Capital Lease Obligatio48

Debt, Capital Lease Obligations and Other Financing - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015	Sep. 27, 2014	May 05, 2017
Debt Instrument [Line Items]
Amount borrowed	$ 331,076,000	$ 625,000,000	$ 483,000,000
Amount of debt outstanding	283,000,000	250,000,000
Non-cash failed sales leaseback financing obligation	$ 20,500,000	2,900,000	$ 1,200,000
Guadalajara, Mexico
Debt Instrument [Line Items]
Contract and renewal lease term	20 years
Guadalajara, Mexico | Assets Held under Capital Leases
Debt Instrument [Line Items]
Estimated loss if Company does not exercise both renewal options	$ 4,100,000
Estimated loss if Company exercises first but not second renewal option	$ 800,000
Guadalajara, Mexico | Failed Sale-Leaseback of Building Shell
Debt Instrument [Line Items]
Non-cash failed sales leaseback financing obligation				$ 8,600,000
Balance of related non-cash failed sales leaseback financing obligation		8,400,000
Senior Notes | 5.20% Senior Notes
Debt Instrument [Line Items]
Interest rate	5.20%
Amount of debt outstanding	$ 175,000,000	$ 175,000,000
Capital Lease Obligations
Debt Instrument [Line Items]
Weighted average interest rate	4.51%	5.58%
Value of non-cash transaction	$ 15,700,000
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum commitment	300,000,000
Amount credit facility may be further increased	500,000,000
Highest daily borrowings	151,000,000
Average daily borrowings	$ 106,700,000
Interest rate at period end	2.358%
Annual commitment fee	0.175%
Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Amount borrowed	$ 331,000,000
Amount repaid	298,000,000
Amount of debt outstanding	$ 108,000,000	$ 75,000,000			$ 75,000,000
Revolving Credit Facility | Line of Credit | LIBOR
Debt Instrument [Line Items]
Borrowing rate	1.125%

Debt, Capital Lease Obligatio49

Debt, Capital Lease Obligations and Other Financing - Schedule of Aggregate Scheduled Maturities of Debt Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Debt and Capital Lease Obligations [Abstract]
2,018	$ 283,000
2,019	0
2,020	0
2,021	0
2,022	0
Thereafter	0
Total	$ 283,000	$ 250,000

Debt, Capital Lease Obligatio50

Debt, Capital Lease Obligations and Other Financing - Schedule of Aggregate Scheduled Maturities of Obligations Under Capital Leases (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2017USD ($)option
Capital Leased Assets [Line Items]
2,018	$ 3,934
2,019	2,705
2,020	1,648
2,021	820
2,022	651
Thereafter	21,143
Future minimum payments	30,901
Guadalajara, Mexico
Capital Leased Assets [Line Items]
2,018	1,513
2,019	1,550
2,020	1,589
2,021	1,629
2,022	1,670
Thereafter	3,466
Future minimum payments	11,417
2025 through 2029 (first five-year renewal option)	9,451
2030 through 2034 (second five-year renewal option)	10,870
Total	$ 31,738
Base lease agreement term	10 years
Number of renewal options | option	2
Term of renewal options	5 years

Derivatives and Fair Value Me51

Derivatives and Fair Value Measurements - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015	May 05, 2017
Estimated unrealized gains, net of tax, expected to be reclassified in next 12 months	$ 2,000,000
Amount of debt outstanding	283,000,000	$ 250,000,000
Gains (losses) recognized in income for derivatives related to ineffective portions and amounts excluded from effectiveness testing	0	0	$ 0
Revolving Credit Facility | Line of Credit
Amount of debt outstanding	108,000,000	75,000,000		$ 75,000,000
Derivatives designated as hedging instruments | Derivatives in Cash Flow Hedging Relationships | Forward currency forward contracts
Notional amount of forward exchange contracts	67,000,000	73,700,000
Fair value of derivative asset	2,000,000
Fair value of derivative liability		500,000
Derivatives designated as hedging instruments | Derivatives in Cash Flow Hedging Relationships | Interest rate swaps
Notional amount of forward exchange contracts		75,000,000		$ 75,000,000
Fixed interest rate				0.875%
Derivatives not designated as hedging instruments | Forward currency forward contracts
Notional amount of forward exchange contracts	10,600,000	109,600,000
Fair value of derivative asset		$ 100,000
Fair value of derivative liability	$ 100,000

Derivatives and Fair Value Me52

Derivatives and Fair Value Measurements - Schedule of Fair Values of Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Interest rate swaps | Prepaid expenses and other | Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 0	$ 0
Interest rate swaps | Other accrued liabilities | Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	132
Forward currency forward contracts | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives		100
Liability Derivatives	100
Forward currency forward contracts | Prepaid expenses and other | Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives	2,024	0
Forward currency forward contracts | Prepaid expenses and other | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives	35	182
Forward currency forward contracts | Other accrued liabilities | Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	486
Forward currency forward contracts | Other accrued liabilities | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 118	$ 130

Derivatives and Fair Value Me53

Derivatives and Fair Value Measurements - Schedule of the Effect of Derivative Instruments on the Statements of Operations (Details) - Derivatives designated as hedging instruments - Derivatives in Cash Flow Hedging Relationships - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion)	$ (10)	$ (16)	$ (1,258)
Forward currency forward contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion)	$ (848)	$ 5,311	$ (15,660)

Derivatives and Fair Value Me54

Derivatives and Fair Value Measurements - Gain (Loss) Recognized in Income from Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Derivatives designated as hedging instruments | Derivatives in Cash Flow Hedging Relationships | Interest rate swaps | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion)	$ (142)	$ (381)	$ (579)
Derivatives designated as hedging instruments | Derivatives in Cash Flow Hedging Relationships | Interest rate swaps | Income tax expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion)	(84)	0	0
Derivatives designated as hedging instruments | Derivatives in Cash Flow Hedging Relationships | Forward currency forward contracts | Selling and administrative expenses
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion)	(317)	(350)	(597)
Derivatives designated as hedging instruments | Derivatives in Cash Flow Hedging Relationships | Forward currency forward contracts | Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion)	(3,041)	(3,261)	(4,843)
Derivatives designated as hedging instruments | Derivatives in Cash Flow Hedging Relationships | Treasury Rate Locks | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated OCL into Income (Effective Portion)	321	320	324
Derivatives not designated as hedging instruments | Forward currency forward contracts | Miscellaneous income (expense)
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain on Derivatives Recognized in Income	$ 2,153	$ 121	$ 164

Derivatives and Fair Value Me55

Derivatives and Fair Value Measurements - Schedule of Fair Value Measurements Using Input Levels (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Interest rate swaps
Derivative liability		$ (132)
Forward currency forward contracts
Derivative asset	$ 1,941
Derivative liability		(434)
Level 1 | Interest rate swaps
Derivative liability		0
Level 1 | Forward currency forward contracts
Derivative asset	0
Derivative liability		0
Level 2 | Interest rate swaps
Derivative liability		(132)
Level 2 | Forward currency forward contracts
Derivative asset	1,941
Derivative liability		(434)
Level 3 | Interest rate swaps
Derivative liability		0
Level 3 | Forward currency forward contracts
Derivative asset	$ 0
Derivative liability		$ 0

Income Taxes - Schedule of Dom

Income Taxes - Schedule of Domestic and Foreign Components of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Income Tax Disclosure [Abstract]
U.S.	$ (35,209)	$ (26,796)	$ (32,480)
Foreign	157,032	114,190	138,775
Income before income taxes	$ 121,823	$ 87,394	$ 106,295

Income Taxes - Schedule of Inc

Income Taxes - Schedule of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Current:
Federal	$ 78	$ 0	$ 0
State	33	(15)	(397)
Foreign	10,016	11,312	12,957
Current Total	10,127	11,297	12,560
Deferred:
Federal	77	0	0
State	38	24	(399)
Foreign	(481)	(354)	(198)
Deferred Total	(366)	(330)	(597)
Income tax expense	$ 9,761	$ 10,967	$ 11,963

Income Taxes - Schedule of Rec

Income Taxes - Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax Rates (Details)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	35.00%	35.00%	35.00%
Increase (decrease) resulting from:
Permanent differences	1.20%	1.60%	1.30%
Foreign tax rate differences	(39.90%)	(36.30%)	(38.00%)
Disregarded entity benefit	(0.90%)	(1.80%)	(1.20%)
Dividend repatriation	0.00%	32.90%	0.00%
Valuation allowances	12.20%	(18.70%)	16.50%
Other, net	0.40%	(0.10%)	(2.30%)
Effective income tax rate	8.00%	12.60%	11.30%

Income Taxes - Narrative (Deta

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Income tax expense	$ 9,761,000	$ 10,967,000	$ 11,963,000
Additions to valuation allowance	14,900,000		17,500,000
Foreign earnings repatriated		100,000,000
Net impact to fiscal 2017 opening retained earnings balance	0
Increase to valuation allowance	20,700,000
Aggregate undistributed earnings of foreign subsidiaries for which deferred income tax liability has not been recorded	990,700,000
Uncertain tax benefits	3,100,000
Unrecognized tax benefits that would reduce company's effective tax rate if recognized	800,000	600,000
Total accrued penalties and net accrued interest with respect to income taxes	200,000	200,000	200,000
Expense recognized for accrued penalties and net accrued interest (less than)	100,000	100,000	100,000
Other liabilities (noncurrent)
Uncertain tax benefits	800,000
Deferred income taxes (noncurrent asset)
Uncertain tax benefits	2,300,000
State Jurisdiction
Net operating loss carryforwards	181,500,000
AMER
Increase to valuation allowance	18,400,000
EMEA
Increase to valuation allowance	2,300,000
APAC
Tax reductions related to tax holiday	$ 37,500,000	$ 27,100,000	$ 29,900,000
Tax reductions related to tax holiday, basic (in dollars per share)	$ 1.11	$ 0.81	$ 0.89
Tax reductions related to tax holiday, diluted (in dollars per share)	$ 1.08	$ 0.79	$ 0.87
Accounting Standards Update 2016-09
Net operating loss carryforwards		$ 4,900,000
Increase to valuation allowance		4,900,000
Accounting Standards Update 2016-09 | Retained Earnings
Net impact to fiscal 2017 opening retained earnings balance		$ 0

Income Taxes - Schedule of Com

Income Taxes - Schedule of Components of Net Deferred Income Tax Asset (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 01, 2016
Deferred income tax assets:
Loss/credit carryforwards	$ 44,831	$ 24,017
Inventories	7,710	7,527
Accrued benefits	25,811	25,493
Allowance for bad debts	319	461
Other	2,732	2,822
Total gross deferred income tax assets	81,403	60,320
Less valuation allowances	(61,668)	(41,002)
Deferred income tax assets	19,735	19,318
Deferred income tax liabilities:
Property, plant and equipment	14,443	14,400
Other	0	84
Deferred income tax liabilities	14,443	14,484
Net deferred income tax assets	$ 5,292	$ 4,834

Income Taxes - Schedule of R61

Income Taxes - Schedule of Reconciliation of Beginning and Ending Amounts of Unrecognized Income Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of fiscal year	$ 2,799	$ 2,353	$ 2,368
Gross increases for tax positions of prior years	184	534	73
Gross increases for tax positions of the current year	163	0	0
Gross decreases for tax positions of prior years	(31)	(88)	(88)
Balance at end of fiscal year	$ 3,115	$ 2,799	$ 2,353

Earnings Per Share - Reconcili

Earnings Per Share - Reconciliation of Amounts Utilized in Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Jan. 02, 2016	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Earnings Per Share [Abstract]
Net income	$ 29,009	$ 25,579	$ 29,295	$ 28,179	$ 19,093	$ 26,099	$ 16,787	$ 14,448	$ 112,062	$ 76,427	$ 94,332
Basic weighted average common shares outstanding (in shares)									33,612	33,374	33,618
Dilutive effect of share-based awards outstanding (in shares)									941	724	761
Diluted weighted average shares outstanding (in shares)									34,553	34,098	34,379
Earnings per share:
Basic (in dollars per share)	$ 0.86	$ 0.76	$ 0.87	$ 0.84	$ 0.57	$ 0.78	$ 0.50	$ 0.43	$ 3.33	$ 2.29	$ 2.81
Diluted (in dollars per share)	$ 0.84	$ 0.74	$ 0.84	$ 0.82	$ 0.56	$ 0.76	$ 0.50	$ 0.42	$ 3.24	$ 2.24	$ 2.74

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - shares shares in Millions	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Share-based awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	0.1	0.8	0.7

Operating Lease Commitments -

Operating Lease Commitments - Schedule of Future Minimum Annual Payments on Operating Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Leases, Operating [Abstract]
Rent expenses under operating leases	$ 13,700	$ 13,600	$ 14,400
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2,018	9,390
2,019	8,191
2,020	7,873
2,021	4,279
2,022	1,718
Thereafter	5,106
Total future minimum operating lease payments	$ 36,557

Benefit Plans - Narrative (Det

Benefit Plans - Narrative (Details)	1 Months Ended	12 Months Ended
	Mar. 31, 2017USD ($)	Sep. 30, 2017USD ($)installment$ / sharesshares	Oct. 01, 2016USD ($)$ / sharesshares	Oct. 03, 2015USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 17,400,000	$ 19,300,000	$ 13,300,000
Deferred tax benefits recognized related to equity awards		$ 0
Deferred tax benefits recognized related to equity awards			0	0
Employer matching contribution, percent of eligible earnings (up to)		4.00%
Amount of contributions		$ 7,500,000	7,400,000	7,200,000
SERP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation liability		12,000,000	9,800,000
Total value of assets held by trust		12,000,000	9,500,000
Amount of contributions made to participants' SERP accounts		$ 1,200,000	500,000	500,000
Noncash settlement and re-investment amount due to change in trustee	$ 10,300,000
Other Postretirement Benefit Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of deferred compensation agreements		15 years
Deferred compensation liability		$ 300,000	600,000
Total value of assets held by trust		9,700,000	9,300,000
Amount of payments made to participants		$ 400,000	$ 800,000	$ 900,000
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		3 years
Unrecognized compensation expense		$ 4,400,000
Unrecognized compensation expense, weighted average period of recognition		2 years 1 month
Payout, percent of shares granted		100.00%
Vested (in shares) | shares		100,000
Granted (in shares) | shares		100,000	100,000	100,000
PSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		0.00%
Number of shares that may be issued (in shares) | shares		0
PSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		200.00%
Number of shares that may be issued (in shares) | shares		400,000
PSUs | Vest Based on Market Condition - Relative TSR of Common Stock Compared to Companies in Russell 3000 Index
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		50.00%
Payout, percent of shares granted		98.00%
Payout at target, TSR threshold percent of companies in Russell 3000 Index during performance period		50.00%
PSUs | Vest Based on Performance Condition - Three-Point Annual Average of Absolute Economic Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		50.00%
Payout at target, average economic return threshold percentage over performance period		2.50%
Options and SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per share (in dollars per share) | $ / shares		$ 15.66	$ 12.82	$ 14.55
Fair value vested		$ 3,500,000	$ 3,600,000	$ 5,500,000
Total intrinsic value exercised		10,200,000	$ 7,400,000	$ 7,700,000
Unrecognized compensation expense		$ 700,000
Unrecognized compensation expense, weighted average period of recognition		8 months 24 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense		$ 16,600,000
Unrecognized compensation expense, weighted average period of recognition		1 year 6 months 10 days
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized under the plan (in shares) | shares		3,200,000
2016 Plan | Cash Incentive Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-term cash awards per employee that may be granted annually		$ 4,000,000
2016 Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual vesting installments | installment		2
Term		10 years
2016 Plan | SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual vesting installments | installment		2
Term		7 years
2016 Plan | PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		3 years	3 years
2016 Plan | PSUs | Vest Based on Market Condition - Relative TSR of Common Stock Compared to Companies in Russell 3000 Index
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		50.00%
2016 Plan | PSUs | Vest Based on Performance Condition - Three-Point Annual Average of Absolute Economic Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		50.00%
2016 Plan | RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		3 years

Benefit Plans - Schedule of St

Benefit Plans - Schedule of Stock Option and Stock Appreciation Rights Activity (Details) - Options and SARs - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Number of Options/SARs
Outstanding at beginning of period (in shares)	1,461	1,917	2,270
Granted (in shares)	36	229	221
Canceled (in shares)	(4)	(66)	(25)
Exercised (in shares)	(521)	(619)	(549)
Outstanding at end of period (in shares)	972	1,461	1,917
Weighted Average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 34.59	$ 33.27	$ 31.65
Granted (in dollars per share)	45.45	39.52	39.53
Canceled (in dollars per share)	30.88	41.48	36.50
Exercised (in dollars per share)	32.29	31.59	28.93
Outstanding at end of period (in dollars per share)	$ 36.23	$ 34.59	$ 33.27
Aggregate Intrinsic Value
Outstanding at end of period	$ 19,283
Exercisable, Number of Options/SARs (in shares)	865	1,125	1,560
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 35.62	$ 33.11	$ 31.67
Exercisable, Weighted Average Remaining Life (years)	4 years 2 months 15 days
Exercisable, Aggregate Intrinsic Value	$ 17,692

Benefit Plans - Schedule of 67

Benefit Plans - Schedule of Stock Option and Stock Appreciation Rights Information (Details) - Options and SARs shares in Thousands	12 Months Ended
	Sep. 30, 2017$ / sharesshares
Number of Options/SARs Outstanding (in shares) | shares	972
Weighted Average Exercise Price (in dollars per share)	$ 36.23
Weighted Average Remaining Life (years)	4 years 8 months 12 days
Number of Options/SARs Exercisable (in shares) | shares	865
Weighted Average Exercise Price (in dollars per share)	$ 35.62
$14.17 - $31.70
Number of Options/SARs Outstanding (in shares) | shares	244
Weighted Average Exercise Price (in dollars per share)	$ 26.27
Weighted Average Remaining Life (years)	3 years 4 months 25 days
Number of Options/SARs Exercisable (in shares) | shares	244
Weighted Average Exercise Price (in dollars per share)	$ 26.27
$14.17 - $31.70 | Minimum
Range of Exercise Prices, Lower Range Limit (in dollars per share)	14.17
$14.17 - $31.70 | Maximum
Range of Exercise Prices, Upper Range Limit (in dollars per share)	$ 31.70
$31.71 - $37.12
Number of Options/SARs Outstanding (in shares) | shares	279
Weighted Average Exercise Price (in dollars per share)	$ 35.56
Weighted Average Remaining Life (years)	5 years
Number of Options/SARs Exercisable (in shares) | shares	243
Weighted Average Exercise Price (in dollars per share)	$ 35.72
$31.71 - $37.12 | Minimum
Range of Exercise Prices, Lower Range Limit (in dollars per share)	31.71
$31.71 - $37.12 | Maximum
Range of Exercise Prices, Upper Range Limit (in dollars per share)	$ 37.12
$37.13 - $41.84
Number of Options/SARs Outstanding (in shares) | shares	270
Weighted Average Exercise Price (in dollars per share)	$ 40.11
Weighted Average Remaining Life (years)	4 years 11 months
Number of Options/SARs Exercisable (in shares) | shares	252
Weighted Average Exercise Price (in dollars per share)	$ 39.99
$37.13 - $41.84 | Minimum
Range of Exercise Prices, Lower Range Limit (in dollars per share)	37.13
$37.13 - $41.84 | Maximum
Range of Exercise Prices, Upper Range Limit (in dollars per share)	$ 41.84
$41.85 - $45.45
Number of Options/SARs Outstanding (in shares) | shares	179
Weighted Average Exercise Price (in dollars per share)	$ 44.99
Weighted Average Remaining Life (years)	5 years 7 months 35 days
Number of Options/SARs Exercisable (in shares) | shares	126
Weighted Average Exercise Price (in dollars per share)	$ 44.81
$41.85 - $45.45 | Minimum
Range of Exercise Prices, Lower Range Limit (in dollars per share)	41.85
$41.85 - $45.45 | Maximum
Range of Exercise Prices, Upper Range Limit (in dollars per share)	$ 45.45

Benefit Plans - Schedule of Es

Benefit Plans - Schedule of Estimated Option Grants Using Black-Scholes Pricing Model (Details) - Options and SARs	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (years)	5 years 8 months 12 days	5 years 8 months 12 days
Risk-free interest rate	1.50%
Risk-free interest rate, Minimum		1.23%	1.52%
Risk-free interest rate, Maximum		1.87%	1.64%
Expected volatility	34.00%
Expected volatility, Minimum		35.00%	37.00%
Expected volatility, Maximum		37.00%	38.00%
Dividend yield	0.00%	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (years)			4 years 6 months 1 day
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (years)			5 years 8 months 12 days

Benefit Plans - Schedule of Re

Benefit Plans - Schedule of Restricted Stock Unit and Stock Awards Activity (Details) - PSUs and RSUs - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Number of Shares
Units outstanding at beginning of period (in shares)	1,022	796	730
Granted (in shares)	397	499	325
Canceled (in shares)	(22)	(29)	(43)
Vested (in shares)	(329)	(244)	(216)
Units outstanding at end of period (in shares)	1,068	1,022	796
Weighted Average Fair Value at Date of Grant
Units outstanding at beginning of period (in dollars per share)	$ 41.49	$ 38.18	$ 31.97
Granted (in dollars per share)	54.21	39.68	41.46
Canceled (in dollars per share)	41.17	36.84	35.15
Vested (in dollars per share)	43.76	27.77	37.52
Units outstanding at end of period (in dollars per share)	$ 45.97	$ 41.49	$ 38.18
Aggregate Intrinsic Value
Units outstanding at end of period	$ 59,905

Reportable Segments, Geograph70

Reportable Segments, Geographic Information and Major Customers - Reportable Segments Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2017USD ($)	Jul. 01, 2017USD ($)	Apr. 01, 2017USD ($)	Dec. 31, 2016USD ($)	Oct. 01, 2016USD ($)	Jul. 02, 2016USD ($)	Apr. 02, 2016USD ($)	Jan. 02, 2016USD ($)	Sep. 30, 2017USD ($)segment	Oct. 01, 2016USD ($)	Oct. 03, 2015USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment									3
Net sales	$ 669,852	$ 618,832	$ 604,349	$ 635,019	$ 653,064	$ 667,616	$ 618,660	$ 616,664	$ 2,528,052	$ 2,556,004	$ 2,654,290
Operating income (loss)									129,908	99,439	115,436
Other income (expense):
Interest expense									(13,578)	(14,635)	(13,964)
Interest income									5,042	4,242	3,499
Miscellaneous									451	(1,652)	1,324
Income before income taxes									121,823	87,394	106,295
Depreciation									45,330	47,414	48,378
Capital expenditures									38,538	31,123	35,076
Total assets	1,976,182				1,765,819				1,976,182	1,765,819
Corporate
Operating income (loss)									(105,922)	(117,237)	(105,237)
Other income (expense):
Depreciation									4,581	4,497	4,110
Capital expenditures									863	2,549	915
Elimination of inter-segment sales
Net sales									(110,384)	(105,057)	(160,924)
Corporate and eliminations
Other income (expense):
Total assets	44,390				28,416				44,390	28,416
AMER | Operating Segments
Net sales									1,166,346	1,328,760	1,389,017
Operating income (loss)									41,924	64,921	68,585
Other income (expense):
Depreciation									19,694	19,937	17,753
Capital expenditures									18,111	14,389	17,595
Total assets	595,851				590,850				595,851	590,850
APAC | Operating Segments
Net sales									1,279,261	1,161,851	1,285,905
Operating income (loss)									200,103	155,501	160,217
Other income (expense):
Depreciation									15,588	16,874	18,176
Capital expenditures									13,816	10,786	9,590
Total assets	1,163,111				1,009,917				1,163,111	1,009,917
EMEA | Operating Segments
Net sales									192,829	170,450	140,292
Operating income (loss)									(6,197)	(3,746)	(8,129)
Other income (expense):
Depreciation									5,467	6,106	8,339
Capital expenditures									5,748	3,399	$ 6,976
Total assets	$ 172,830				$ 136,636				$ 172,830	$ 136,636

Reportable Segments, Geograph71

Reportable Segments, Geographic Information and Major Customers - Net Sales and Long-Lived Assets (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Jan. 02, 2016	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Net sales	$ 669,852	$ 618,832	$ 604,349	$ 635,019	$ 653,064	$ 667,616	$ 618,660	$ 616,664	$ 2,528,052	$ 2,556,004	$ 2,654,290
Long-lived assets	314,665				291,225				314,665	291,225
Operating Segments | United States
Net sales									984,773	1,134,342	1,303,106
Long-lived assets	110,828				92,152				110,828	92,152
Operating Segments | Malaysia
Net sales									940,045	844,501	926,059
Long-lived assets	74,769				71,596				74,769	71,596
Operating Segments | China
Net sales									339,216	317,350	359,846
Long-lived assets	18,602				19,197				18,602	19,197
Operating Segments | Mexico
Net sales									181,573	194,418	85,911
Long-lived assets	37,237				39,155				37,237	39,155
Operating Segments | Romania
Net sales									114,363	83,712	65,338
Long-lived assets	33,717				30,408				33,717	30,408
Operating Segments | United Kingdom
Net sales									70,163	81,894	70,335
Long-lived assets	6,456				6,594				6,456	6,594
Operating Segments | Germany
Net sales									8,303	4,844	4,619
Long-lived assets	303				307				303	307
Operating Segments | Other Foreign
Long-lived assets	5,126				4,940				5,126	4,940
Elimination of inter-segment sales
Net sales									(110,384)	(105,057)	$ (160,924)
Corporate
Long-lived assets	$ 27,627				$ 26,876				$ 27,627	$ 26,876

Reportable Segments, Geograph72

Reportable Segments, Geographic Information and Major Customers - Narrative (Details) $ in Millions	12 Months Ended
	Sep. 30, 2017USD ($)segment	Oct. 01, 2016USD ($)
Segment Reporting [Abstract]
Other long-term assets and deferred income tax assets | $	$ 44.1	$ 41.2
Number of reportable segments | segment	3
Customer Concentration Risk | Arris | Accounts Receivable
Concentration Risk [Line Items]
Percentage of concentration risk	11.60%
Customer Concentration Risk | Micron | Accounts Receivable
Concentration Risk [Line Items]
Percentage of concentration risk		18.90%

Reportable Segments, Geograph73

Reportable Segments, Geographic Information and Major Customers - Concentration of Risk (Details) - Customer Concentration Risk - Consolidated Net Sales	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
General Electric Company (GE)
Segment Reporting Information [Line Items]
Percentage of concentration risk	12.20%	11.10%	10.60%
Micron Technology, Inc. (Micron)
Segment Reporting Information [Line Items]
Percentage of concentration risk		10.40%
ARRIS Group, Inc. (Arris)
Segment Reporting Information [Line Items]
Percentage of concentration risk		10.10%	12.60%

Guarantees - Narrative (Details

Guarantees - Narrative (Details)	12 Months Ended
	Sep. 30, 2017
Minimum
Product Warranty Liability [Line Items]
Product warranty specification period	12 months
Maximum
Product Warranty Liability [Line Items]
Product warranty specification period	24 months

Guarantees - Schedule of Activ

Guarantees - Schedule of Activity Related to Limited Warranty Liability (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Movement in Standard Product Warranty Accrual [Roll Forward]
Limited warranty liability, beginning balance	$ 6,109	$ 5,847	$ 6,803
Accruals for warranties issued during the period	912	1,777	1,742
Settlements (in cash or in kind) during the period	(2,265)	(1,515)	(2,698)
Limited warranty liability, ending balance	$ 4,756	$ 6,109	$ 5,847

Shareholders' Equity - Narrati

Shareholders' Equity - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015	Jun. 06, 2016	Aug. 20, 2015
Equity, Class of Treasury Stock [Line Items]
Amount repurchased	$ 34,136,000	$ 30,000,000	$ 30,000,000
Class of Warrant or Right [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
2017 Stock Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Authorized repurchase amount				$ 150,000,000
Amount repurchased (in shares)	655,470
Amount repurchased	$ 34,100,000
Average repurchase price (in dollars per share)	$ 52.08
2016 Stock Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Authorized repurchase amount					$ 30,000,000
Amount repurchased (in shares)		760,903
Amount repurchased		$ 30,000,000
Average repurchase price (in dollars per share)		$ 39.43
Preferred Share Purchase Right
Class of Warrant or Right [Line Items]
Number of shares of Series B Junior Participating Preferred Stock entitled to each right (in shares)	0.01
Exercise price per one-hundredth of a Preferred Share (in dollars per share)	$ 125
Minimum percentage of common stock required for Rights exercisable	20.00%

Trade Accounts Receivable Sal77

Trade Accounts Receivable Sale Programs - Narrative (Details) - USD ($)	Oct. 19, 2017	Mar. 17, 2017	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Amount Received From Trade Accounts Receivable Sold To Third Party [Line Items]
Trade accounts receivable sold			$ 418,000,000	$ 65,600,000	$ 93,100,000
Cash proceeds			415,800,000	$ 65,000,000	$ 92,400,000
BTMU RPA
Amount Received From Trade Accounts Receivable Sold To Third Party [Line Items]
Maximum facility amount			$ 120,000,000
Minimum prior notice required to cancel automatic extension			10 days
BTMU RPA | Subsequent Event
Amount Received From Trade Accounts Receivable Sold To Third Party [Line Items]
Maximum facility amount	$ 160,000,000
HSBC RPA
Amount Received From Trade Accounts Receivable Sold To Third Party [Line Items]
Maximum facility amount		$ 60,000,000

Restructuring and Other Charg78

Restructuring and Other Charges - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Restructuring and Related Activities [Abstract]
Restructuring and other charges	$ 0	$ 7,034,000	$ 1,691,000

Restructuring and Other Charg79

Restructuring and Other Charges - Restructuring Accrual Activity (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Restructuring Reserve [Roll Forward]
Accrual balance, beginning of period	$ 842,000	$ 0	$ 142,000
Restructuring and other charges	0	7,034,000	1,691,000
Amounts utilized	(842,000)	(6,192,000)	(1,833,000)
Accrual balance, end of period	0	842,000	0
Employee Termination and Severance Costs
Restructuring Reserve [Roll Forward]
Accrual balance, beginning of period	684,000	0	142,000
Restructuring and other charges	0	5,255,000	144,000
Amounts utilized	(684,000)	(4,571,000)	(286,000)
Accrual balance, end of period	0	684,000	0
Lease Obligations and Other Exit Costs
Restructuring Reserve [Roll Forward]
Accrual balance, beginning of period	158,000	0	0
Restructuring and other charges	0	1,779,000	1,547,000
Amounts utilized	(158,000)	(1,621,000)	(1,547,000)
Accrual balance, end of period	$ 0	$ 158,000	$ 0

Quarterly Financial Data (Una80

Quarterly Financial Data (Unaudited) - Schedule Of Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Jan. 02, 2016	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Quarterly Financial Data [Abstract]
Net sales	$ 669,852	$ 618,832	$ 604,349	$ 635,019	$ 653,064	$ 667,616	$ 618,660	$ 616,664	$ 2,528,052	$ 2,556,004	$ 2,654,290
Gross profit	66,514	61,185	63,800	64,356	61,530	62,498	53,272	50,059	255,855	227,359	239,550
Net income	$ 29,009	$ 25,579	$ 29,295	$ 28,179	$ 19,093	$ 26,099	$ 16,787	$ 14,448	$ 112,062	$ 76,427	$ 94,332
Earnings per share:
Basic (in dollars per share)	$ 0.86	$ 0.76	$ 0.87	$ 0.84	$ 0.57	$ 0.78	$ 0.50	$ 0.43	$ 3.33	$ 2.29	$ 2.81
Diluted (in dollars per share)	$ 0.84	$ 0.74	$ 0.84	$ 0.82	$ 0.56	$ 0.76	$ 0.50	$ 0.42	$ 3.24	$ 2.24	$ 2.74

Schedule II - Valuation and Q81

Schedule II - Valuation and Qualifying Accounts - Schedule of Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Allowance for losses on accounts receivable (deducted from the asset to which it relates)
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 2,368	$ 879	$ 1,188
Additions charged to costs and expenses	566	1,492	581
Additions charged to other accounts	0	0	0
Deductions	(1,954)	(3)	(890)
Balance at end of period	980	2,368	879
Valuation allowance on deferred income tax assets (deducted from the asset to which it relates)
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	41,002	58,343	41,935
Additions charged to costs and expenses	20,678	1,121	16,408
Additions charged to other accounts	0	0	0
Deductions	(12)	(18,462)	0
Balance at end of period	$ 61,668	$ 41,002	$ 58,343