Microsemi (MSCC) 10-K 16 Nov 16 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Thousands	12 Months Ended
	Oct. 02, 2016	Nov. 04, 2016	Apr. 01, 2016
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Oct. 2, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Trading Symbol	MSCC
Entity Registrant Name	MICROSEMI CORP
Entity Central Index Key	310,568
Current Fiscal Year End Date	--10-02
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		114,649,086
Entity Public Float			$ 4,360,000

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Current assets:
Cash and cash equivalents	$ 189.5	$ 256.4
Accounts receivable, net of allowances of $41.7 at October 2, 2016 and $26.0 at September 27, 2015	245.2	186.9
Inventories	213.1	227.2
Disposal Group, Including Discontinued Operation, Assets, Current	13.9	0
Other current assets	73.2	39.9
Total current assets	734.9	710.4
Property and equipment, net	174.9	152.7
Goodwill	2,479.4	1,139.3
Intangible assets, net	934.6	357.8
Deferred income taxes, net	37.3	34.9
Other assets	61.9	36.9
TOTAL ASSETS	4,423	2,432
Current liabilities:
Accounts payable	112.8	82.3
Accrued liabilities	166.1	86.8
Current maturity of credit facility	40.7	32.5
Total current liabilities	319.6	201.6
Credit facility	2,138.5	953.9
Deferred income taxes	120.2	23
Other long-term liabilities	115.8	46.3
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $1.00 par value; authorized 1.0 shares; none issued	0	0
Common stock, $0.20 par value; 250.0 authorized, 113.6 issued and outstanding at October 2, 2016 and 95.1 issued and outstanding at September 27, 2015	22.7	19
Capital in excess of par value of common stock	1,357.8	808.1
Retained earnings	350.6	383.2
Accumulated other comprehensive income (loss)	(2.2)	(3.1)
Total stockholders' equity	1,728.9	1,207.2
Total liabilities and stockholders' equity	$ 4,423	$ 2,432

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 41.7	$ 26
Preferred stock, par value	$ 1	$ 1
Preferred stock, authorized	1,000	1,000
Preferred stock, issued	0	0
Common stock, par value	$ 0.20	$ 0.20
Common stock, authorized	250,000,000	250,000,000
Common stock, issued	113,600,000	95,100,000
Common stock, outstanding	113,600,000	95,100,000

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Income Statement [Abstract]
Net sales	$ 1,655	$ 1,245.6	$ 1,138.3
Cost of sales	717.9	561.3	526.8
Gross profit	937.1	684.3	611.5
Operating expenses:
Selling, general and administrative	352.4	249.5	241
Research and development costs	309.1	200.3	192
Amortization of intangible assets	161.2	96.5	92.8
Restructuring and severance charges	60.7	15.4	31.5
Total operating expenses	883.4	561.7	557.3
Operating income	53.7	122.6	54.2
Interest Income (Expense), Net	(120.1)	(27.3)	(27.8)
Other income (expenses):
Other, net	41	1.6	(2.5)
Total other expense	(79.1)	(25.7)	(30.3)
Income (loss) before income taxes	(25.4)	96.9	23.9
Income Tax Expense (Benefit)	7.2	12.3	0.8
Net income (loss)	$ (32.6)	$ 84.6	$ 23.1
Earnings (loss) per share:
Basic	$ (0.31)	$ 0.90	$ 0.25
Diluted	$ (0.31)	$ 0.88	$ 0.24
Weighted-average common shares outstanding:
Basic	107	94.2	92.9
Diluted	107	95.9	94.5
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Translation adjustment	$ 4.8	$ (1.6)	$ (0.5)
Unrealized actuarial loss on pension benefits	(3.9)	(0.3)	(0.7)
Other comprehensive income (loss)	0.9	(1.9)	(1.2)
Total comprehensive income (loss)	$ (31.7)	$ 82.7	$ 21.9

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands, shares in Millions	Total	Common Stock	Capital in Excess of Par value of Common Stock	Retained Earnings	Accumulated Other Comprehensive Income
Balance (in shares) at Sep. 29, 2013		93.8
Balance at Sep. 29, 2013	$ 1,032,100	$ 18,800	$ 737,800	$ 275,500	$ 0
Proceeds from exercise of stock options (in shares)		1.5
Proceeds from exercise of stock options	19,200	$ 200	19,000
Tax withholding on restricted stock units	(1,500)		(1,500)
Grants and cancellations of restricted share awards (in shares)		0.3
Grants and cancellations of restricted share awards	0	$ 100	(100)
Issuance of stock awards related to acquisition	3,800		3,714
Stock-based compensation expense	43,900
Stock-based compensation	43,900
Other comprehensive income, net of tax	(1,200)				(1,200)
Net income	23,100			23,100
Balance (in shares) at Sep. 28, 2014		95.6
Balance at Sep. 28, 2014	1,115,600	$ 19,100	799,100	298,600	(1,200)
Proceeds from exercise of stock options (in shares)		2.1
Proceeds from exercise of stock options	48,400	$ 400	48,000
Tax withholding on restricted stock units	(18,100)		(18,100)
Grants and cancellations of restricted share awards (in shares)		0.1
Grants and cancellations of restricted share awards	0	$ 0	0
Stock-based compensation expense	49,800
Stock-based compensation	49,800
Other comprehensive income, net of tax	(1,900)				(1,900)
Repurchase of outstanding common stock (in shares)		(2.7)
Repurchase of outstanding common stock	(75,000)	$ (500)	(74,500)
Net income	84,600			84,600
Balance (in shares) at Sep. 27, 2015		95.1
Balance at Sep. 27, 2015	1,207,200	$ 19,000	808,100	383,200	(3,100)
Stock Issued During Period, Shares, Share-based Compensation, Gross		0.8
Stock Issued During Period, Value, Share-based Compensation, Gross		$ 100
Proceeds from exercise of stock options (in shares)		2.2
Proceeds from exercise of stock options	4,600	$ 400	4,200
Shares Paid for Tax Withholding for Share Based Compensation		1.2
Tax withholding on restricted stock units	(42,500)	$ (200)	(42,300)
Grants and cancellations of restricted share awards (in shares)		0.8
Grants and cancellations of restricted share awards	0	$ 200	(200)
Stock Issued During Period, Shares, Acquisitions		15.8
Issuance of stock awards related to acquisition	474,500	$ 3,200	471,300
Issuance of stock awards related to acquisition (in shares)		0.1
Issuance of stock awards related to acquisition	15,700	$ 0	15,700
Stock-based compensation expense	101,100		101,000
Stock-based compensation	101,100
Other comprehensive income, net of tax	900				900
Net income	(32,600)			(32,600)
Balance (in shares) at Oct. 02, 2016		113.6
Balance at Oct. 02, 2016	$ 1,728,900	$ 22,700	$ 1,357,800	$ 350,600	$ (2,200)

Consolidated Statement of Cash

Consolidated Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Statement of Cash Flows [Abstract]
Gain (Loss) on Disposition of Business	$ (125.5)	$ 0	$ 0
Cash flows from operating activities:
Net income (loss)	(32.6)	84.6	23.1
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	46.1	36.2	32.9
Amortization of intangible assets	161.2	96.5	92.8
Provision for doubtful accounts	0.7	(0.2)	0.1
Amortization of deferred financing costs	33.1	1.6	1.3
Loss on disposition or impairment of assets	1.6	(1.1)	9.8
Deferred income taxes	(32.6)	(8)	(21.5)
Valuation allowance on deferred income taxes	35.3	13.3	17.6
Stock based compensation expense	101.1	49.8	43.9
Change in assets and liabilities (net of acquisitions):
Accounts receivable	(22.1)	13.8	5.2
Inventories	80.2	11.1	10.3
Other current assets	(20.3)	(2.5)	9.2
Other assets	2.2	(7.6)	(1.8)
Accounts payable	(35.8)	(2.9)	(5.5)
Accrued liabilities	(7.7)	(12.9)	(13.5)
Other long-term liabilities	89.7	(2.4)	2.8
Net cash provided by operating activities	274.6	269.3	206.7
Cash flows from investing activities:
Purchases of property and equipment	(48.8)	(44.1)	(39.4)
Proceeds from sale of short term investments	0.4	0.6	41
Proceeds from the divestiture or sale of assets	321	0	0
Proceeds from the sale of investment	0	4.2	0
Payments for acquisitions, net of cash acquired	(1,686.8)	(363.9)	(337.6)
Net cash used in investing activities	(1,414.2)	(403.2)	(336)
Cash flows from financing activities:
Repayments of credit facility	(1,132.4)	(142.7)	(178)
Credit facility issuance costs	(53.8)	(8.7)	(1.5)
Proceeds from credit facility	3,494.3	425	289.5
Extinguishment of debt	(1,198.1)	0	(89.5)
Payments for Repurchase of Common Stock	0	(75)	0
Settlement to terminate capital lease	0	0	(3)
Stock settled tax withholdings	42.4	18.1	1.5
Exercise proceeds from stock awards	5.1	47.6	19.1
Net cash (used in) provided by financing activities	1,072.7	228.1	35.1
Net increase (decrease) in cash and cash equivalents	(66.9)	94.2	(94.2)
Cash and cash equivalents at beginning of year	256.4	162.2	256.4
Cash and cash equivalents at end of year	189.5	256.4	162.2
Supplemental disclosure of cash flow information Cash paid during the year for:
Interest	89.1	27.4	29.2
Income taxes	$ 11.2	$ 3.3	$ 3.9

Description of business and sum

Description of business and summary of significant accounting policies	12 Months Ended
	Oct. 02, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of business and summary of significant accounting policies	Note 1 Description of business and summary of significant accounting policies Description of Business We are a leading designer, manufacturer and marketer of high-performance analog and mixed-signal semiconductor solutions differentiated by power, security, reliability and performance. We offer a comprehensive portfolio of semiconductor and system solutions for aerospace & defense, communications, data center and industrial markets. Products include high-performance and radiation-hardened analog mixed-signal ICs, FPGAs, SoCs and ASICs; power management products; timing and synchronization devices and precise time solutions, setting the world's standard for time; voice processing devices; RF solutions; discrete components; enterprise storage and communication solutions; security technologies and scalable anti-tamper products; Ethernet solutions; Power-over-Ethernet ICs and midspans; as well as custom design capabilities and services. The principal end markets that we serve include Aerospace & Defense, Communications, Data Center, and Industrial. Today, Microsemi products are found in applications such as: communications infrastructure systems, both wireless and wired LAN systems, implantable pacemakers and defibrillators, radar systems, military and commercial satellites and aircraft, and enterprise storage and hyperscale data centers. Fiscal Year We report results of operations on the basis of fifty-two and fifty-three week periods. The fiscal year ended on October 2, 2016 consisted of fifty-three weeks and the fiscal years ended on September 27, 2015 , and September 28, 2014 consisted of fifty-two weeks. In referencing a year, we are referring to the fiscal year ended on the Sunday closest to September 30. Principles of Consolidation and Presentation of Financial Information The consolidated financial statements include the accounts of Microsemi and our subsidiaries. All intercompany transactions and balances have been eliminated. Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the respective reporting periods. Actual results could differ from those estimates. Reclassifications Certain prior year amounts have been reclassified to conform to current year presentation. Cash and Cash Equivalents We consider all short-term, highly liquid investments with an original maturity of three months or less to be cash equivalents. Accounts Receivable and Allowance for Doubtful Accounts Trade accounts receivable are recorded at the invoiced amount and do not bear interest. The accounts receivable amount shown in the balance sheet are trade accounts receivable balances at the respective dates, net of allowance for doubtful accounts. The allowance for doubtful accounts is our best estimate of the amount of probable credit losses in our existing accounts receivable. We determine the allowance based in part on our historical write-off experience and specific review of account balances due. Past due balances are reviewed individually for collectability. All other balances are reviewed on a pooled basis by the age of the receivable. Account balances are charged off against the allowance when we determine it is probable the receivable will not be recovered. We review our allowance for doubtful accounts quarterly. We do not have any off-balance-sheet credit exposure related to our customers. To date, our allowance for doubtful accounts has generally been within management’s estimates. Inventories Inventories are stated at the lower of cost, as determined using the first-in, first-out method, or market. Costs include materials, labor and manufacturing overhead. We evaluate the carrying value of our inventories taking into account such factors as historical and anticipated future sales compared with quantities on hand and the price we expect to obtain for our products in their respective markets. We also evaluate the composition of our inventories to identify any slow-moving, excess or obsolete products. Additionally, inventory write-downs are made based upon such judgments for any inventories that are identified as having a net realizable value less than their cost, which is further reduced by related selling expenses. The net realizable value of our inventories for ongoing operations has generally been within management’s estimates. We have recorded inventory write-downs for discontinued product lines that did not meet gross margin targets, products that are being migrated to newer generations, products that service the large capital spending end markets for which demand has declined, and products related to facility closures. Fair Value of Financial Assets and Liabilities Accounting Standards Codification ("ASC") 825 permits entities to elect the fair value option for certain financial assets and financial liabilities. For financial assets or financial liabilities for which an entity elects the fair value option, ASC 825 requires the entity record the financial asset or financial liability at fair value rather than at historical cost with changes in fair value recorded in the income statement. ASC 825-25 requires upfront costs and fees related to items for which the fair value option is elected shall be recognized in earnings as incurred and not deferred. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. ASC 820 establishes a hierarchy for ranking the quality and reliability of the information used to determine fair values and includes the following classifications: Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data. The following financial assets and liabilities were measured at fair value on a recurring basis using the type of inputs indicated below and are as follows (amounts in millions): Fair Value Measurements Using: Total Level 1 Inputs Level 2 Inputs Level 3 Inputs October 2, 2016 Investment in marketable securities $ 1.3 $ 1.3 $ — $ — September 27, 2015 Investment in marketable securities $ 1.7 $ 1.7 $ — $ — Property and Equipment Property and equipment are stated at lower of cost or realizable values. Depreciation is computed on the straight-line method over the estimated useful lives of the assets. Leasehold improvements are amortized over the shorter of the lease terms or the estimated useful lives. Maintenance and repairs are charged to expense as incurred and the costs of additions and betterments that increase the useful lives of the assets are capitalized. Long-Lived Assets We assess the impairment of long-lived assets whenever events or changes in circumstances indicate their carrying value may not be recoverable from the undiscounted estimated future cash flows expected to result from their use. We are required to make judgments and assumptions in identifying those events or changes in circumstances that may trigger impairment. Some of the factors we consider include: • Significant decrease in the market value of an asset. • Significant changes in the extent or manner for which the asset is being used or in its physical condition including manufacturing plant closures. • A significant change, delay or departure in our business strategy related to the asset. • Significant negative changes in the business climate, industry or economic conditions. • Current period operating losses or negative cash flow combined with a history of similar losses or a forecast indicates continuing losses associated with the use of an asset. If events or circumstances indicate the carrying amount of a long-lived asset or asset group may not be recoverable and the expected undiscounted future cash flows attributable to the asset group are less than the carrying value, an impairment loss equal to the excess of the carrying value of the assets within the asset group over their fair value is recorded. The appropriate asset group is determined based on the lowest level of largely independent cash inflows and outflows for the related assets. Depending on the nature of the primary assets in the asset group, fair value is estimated using one of several approaches including replacement cost, appraised values, market quotes or estimated expected future cash flows using a discount rate commensurate with the risk involved. Goodwill and Intangible Assets We account for goodwill on an impairment-only approach and amortize intangible assets with definite useful lives over the benefit period, which approximates straight-line expense over the respective useful lives. We assess qualitative factors to determine whether it is more likely than not an indefinite-lived intangible asset such as goodwill is impaired as the basis for determining whether a quantitative impairment test is required. We assess definite-lived intangible assets for impairment whenever events or changes in circumstances indicate the carrying value of an asset may not be fully recoverable. Whenever we determine there has been an impairment of goodwill or other intangible assets with indefinite lives, we will record an impairment charge against earnings. We operate as one reporting unit and an impairment charge would equal the excess of the carrying value of goodwill in our one reporting unit over its then fair value. The identification of intangible assets and determination of the fair value and useful lives are subjective in nature and often involve the use of significant estimates and assumptions. The judgments made in determining the estimated useful lives assigned to each class of assets can significantly affect net income. We completed our most recent qualitative analysis during the fourth quarter of 2016 and noted no significant factors existed during the fiscal year to indicate it was more likely than not the fair value of the reporting unit is less than its carrying amount. Business Combinations The Company allocates the fair value of the purchase consideration of its acquisitions to the tangible assets, liabilities, and intangible assets acquired, including in-process research and development (“IPR&D”), based on their estimated fair values. Purchase price allocations for business acquisitions require significant judgments, particularly with regards to the determination of value of identifiable assets, liabilities, and goodwill. Often third party specialists are used to assist in area of valuation requiring complex estimation. The excess of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. IPR&D is initially capitalized at fair value as an intangible asset with an indefinite life and assessed for impairment thereafter. When a project underlying reported IPR&D is completed, the corresponding amount of IPR&D is reclassified as an amortizable purchased intangible asset and is amortized over the asset’s estimated useful life. Acquisition-related expenses are recognized separately from the business combination and are expensed as incurred. Revenue Recognition, Sales Returns and Allowances We primarily recognize revenue from customers, including distributors, when title and risk of loss have passed to the customer provided that: 1) evidence of an arrangement exists; 2) delivery has occurred; 3) the fee is fixed or determinable; and 4) collectability is reasonably assured. For substantially all sales, revenue is recognized, net of estimated returns and discounts, at the time the product is shipped. We enter into distribution agreements that permit rights to limited stock rotations, returns, price protection, and volume purchase and other discounts. We provide an estimated allowance for these rights and record a corresponding reduction in revenue. Our estimated allowance is based on several factors including past history and notification from customers of pending activity. Actual activity under such rights have been within management’s expectations. We also derive a portion of our revenue from fixed-price contracts. Revenue for these contracts is recorded under a percentage of completion method, which is based on the ratio of total costs incurred to date to estimated total costs at completion. Actual costs have been within management’s expectations. Gross profit expected to be realized on fixed-price contracts is based on periodic estimates of total revenues and costs for each contract. Losses on contracts are accrued when estimated total costs are expected to exceed total revenues. Occasionally, we will enter into contracts on a cost plus fee basis. We recognize revenue based on reimbursements for actual expenses plus the contractually agreed upon fee with the customer. Research and Development We expense the cost of research and development as incurred. Research and development expenses principally comprise payroll and related costs, supplies, and the cost of prototypes. Restructuring Charges We recognize a liability for restructuring costs when the liability is incurred. The restructuring accruals are based upon management estimates at the time they are recorded and can change depending upon changes in facts and circumstances subsequent to the date the original liability is recorded. The main components of our restructuring charges are workforce reductions and elimination of excess facilities. Workforce-related charges are accrued when it is determined a liability exists, which is generally when individuals have been notified of their expected termination dates and expected severance payments and when formal severance plans exist, when the severance payments are probable and reasonably estimable. The elimination of excess facilities results in charges for lease termination fees, future contractual commitments to pay lease charges net of estimated sublease income, facility remediation costs and moving costs to remove property and equipment from the facilities. We recognize charges for elimination of excess facilities when we have vacated the premises or ceased use of a functionally separate portion of the facility. Stock-Based Compensation Compensation expense for stock options and stock appreciation rights was calculated based on the on the service period of the grant and the grant date or assumption date fair value using the Black-Scholes pricing model. All stock appreciation rights we have granted or assumed are stock-settled. Stock options and stock appreciation rights are granted at exercise prices equal to the closing price of our common stock on the date of grant. Assumed stock options and stock appreciation rights are granted at exercise prices determined in accordance with the acquisition agreement. Expected life and forfeiture rates were estimated based primarily on historical data that were stratified between members of the Board of Directors, executive employees and all other recipients. Expected volatility was estimated based on historical volatility using equally weighted daily price observations over a period approximately equal to the expected life of each option. The risk free interest rate is based on the implied yield currently available on U.S. Treasury securities with an equivalent remaining term. No dividends are expected to be paid. Compensation expense for restricted shares was calculated based on the service period of the grant and the closing price of our common stock on the date of grant. Restricted shares are subject to forfeiture if a participant does not meet length of service requirements. Restricted stock awards granted to employees typically vest over a three year period and awards granted to non-employee directors vest in accordance with our director compensation policy. Compensation expense for performance stock units was calculated based upon expected achievement of the performance metrics specified in the grant and the closing price of our common stock on the date of grant, or when a grant contains a market condition, the grant date fair value using a Monte Carlo simulation. The Monte Carlo simulation incorporates estimates of the potential outcomes of the market condition on the grant date fair value of each award. Accounting For Income Taxes We account for income taxes under the asset and liability method, whereby 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. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. We evaluate the need to establish a valuation allowance for deferred tax assets based upon the amount of existing temporary differences, the period in which they are expected to be recovered and expected levels of taxable income. A valuation allowance to reduce deferred tax assets are established when it is more likely than not some or all of the deferred tax assets will not be realized. We recognize uncertain tax positions when they meet a more-likely-than-not threshold. We recognize potential accrued interest and penalties related to unrecognized tax benefits as income tax expense. We file U.S. federal, state, and foreign income tax returns in jurisdictions with varying statutes of limitations. We establish liabilities for possible assessments by tax authorities resulting from known tax exposures including, but not limited to, international tax issues and certain tax credits. While we believe our reported results are appropriate, any significant adjustments could have a material adverse effect on our results of operations, cash flows and financial position if not resolved within management expectations. Segment Information We use the management approach for segment disclosure, which designates the internal organization that is used by management for making operating decisions and assessing performance as the source of our reportable segments. We manage our business on the basis of one reportable segment, as a manufacturer of semiconductors in different geographic areas, including the United States, Europe and Asia. Foreign Currency All of our significant subsidiaries outside the United States use the United States dollar ("USD") as their functional currency. We have one subsidiary in China that uses the Chinese renminbi ("RMB") as its functional currency. For subsidiaries that use USD as the functional currency, assets and liabilities are remeasured to USD at the exchange rate in effect at the balance sheet date except for non-monetary assets and capital accounts which are measured at historical rates; revenues, expenses, gains and losses are remeasured at rates of exchange that approximate the rates in effect at the transaction date. For subsidiaries that use the local currency as the functional currency, all assets and liabilities are translated to USD using exchange rates in effect at the end of the period. Resulting translation gains or losses are recognized as a component of other comprehensive income. We also conduct a relatively small portion of our business in a number of foreign currencies, principally the European Union Euro, Canadian Dollar, British Pound, Israeli Shekel and Chinese RMB. Earnings Per Share Basic earnings per share have been computed based upon the weighted-average number of common shares outstanding during the respective periods. Diluted earnings per share have been computed, when the result is dilutive, using the treasury stock method for stock awards outstanding during the respective periods. Earnings per share for 2016 , 2015 and 2014 were calculated as follows (amounts in millions, except per share data): Fiscal Years 2016 2015 2014 Basic Net (loss) income $ (32.6 ) $ 84.6 $ 23.1 Weighted-average common shares outstanding 107.0 94.2 92.9 Basic (loss) earnings per share $ (0.31 ) $ 0.90 $ 0.25 Diluted Net (loss) income $ (32.6 ) $ 84.6 $ 23.1 Weighted-average common shares outstanding for basic 107.0 94.2 92.9 Dilutive effect of stock awards — 1.7 1.6 Weighted-average common shares outstanding on a diluted basis 107.0 95.9 94.5 Diluted (loss) earnings per share $ (0.31 ) $ 0.88 $ 0.24 For 2016 , all stock awards were excluded from the computation of diluted EPS as we reported a net loss. For 2015 and 2014 , 0.2 million and 2.8 million awards, respectively, were excluded from the computation of diluted EPS as these stock awards would have been anti-dilutive. Concentration of Credit Risk and International Sales Concentrations of credit risk exist because we rely on a number of customers whose principal sales are to the U.S. Government. Approximately 30% of total net sales in 2016 were in the Aerospace & Defense end market and while we service defense markets outside of the United States, a portion of sales in this end market correlate to sales to U.S. government agencies, customers whose principal sales are to the U.S. government agencies or to subcontractors whose material sales are to the U.S. government agencies. We, as a subcontractor, sell our products to higher-tier subcontractors or to prime contractors based upon purchase orders that usually do not contain all of the conditions included in the prime contract with the U.S. Government. However, these sales are usually subject to termination and/or price renegotiations by virtue of their reference to a U.S. Government prime contract. Therefore, we believe all of our product sales that ultimately are sold to the U.S. Government may be subject to termination, at the convenience of the U.S. Government or to price renegotiations under the Renegotiation Act. In addition, the shutdown of non-essential U.S. Government services in October 2013 and any future government shutdowns may significantly increase the risk of contract terminations or renegotiations. At least one of our contracts has been terminated in the past due to the termination of the underlying government contract. There can be no assurance we will not have contract termination or price renegotiation in the future, and any such termination or renegotiation could have a material adverse impact upon our revenues and results of operations. In addition, net sales to international markets represent a significant portion of total net sales. Our net sales to international customers represented 62% , 51% and 47% of consolidated net sales for 2016 , 2015 and 2014 , respectively. These sales were principally to customers in Europe and Asia. We maintain reserves for potential credit losses and such losses have been within management’s expectations. Recently Adopted Accounting Pronouncement In November 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-17, Balance Sheet Classification of Deferred Taxes, which requires all deferred tax assets and liabilities, as well as related valuation allowances, to be classified as noncurrent rather than as current and non-current based on the classification of the related assets and liabilities. The guidance is effective for annual and interim reporting periods beginning after December 15, 2016, and may be applied either prospectively or retrospectively. Early adoption is permitted. We elected to early adopt the provisions of this update at the beginning of our fourth quarter of fiscal 2016 and accordingly has classified deferred tax assets and liabilities, together with the corresponding valuation allowance as noncurrent in the consolidated balance sheet. We adopted the provisions of this update retrospectively and therefore reclassified and reduced $26.2 million of current deferred income tax assets, increased $8.1 million of noncurrent deferred income tax assets and reduced $18.1 million of noncurrent deferred income tax liabilities in our fiscal year 2015 comparative consolidated balance sheet. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. Several aspects of the accounting for share-based payment award transactions are simplified, including: (a) income tax consequences; (b) classification of awards as either equity or liabilities; (c) classification on the statement of cash flows; and (d) classification of related deferred tax balances as non-current. The amendments in this update are effective for annual periods beginning after December 16, 2016, and interim periods within those fiscal years. Early adoption is permitted. We elected to early adopt this ASU during our fiscal year 2016 and adoption did not impact our consolidated balance sheets, results of operations or cash flows. In August 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. The standard provides guidance for eight targeted changes with respect to how cash receipts and cash payments are classified in the statements of cash flows, with the objective of reducing diversity in practice. The standard is effective for financial statements issued for fiscal years beginning after December 15, 2017 (The Company's fiscal quarter of fiscal 2019), with early adoption permitted. We elected to early adopt this new guidance and accordingly have classified cash payments made during the second quarter of our fiscal year 2016 related to debt extinguishment amounting to approximately $61.3 million as cash flows used in financing activities that was previously reported in our quarterly consolidated financial statements as cash flows used in operating activities. The early adoption this ASU did not impact our prior period consolidated statements of cash flows. Recently Issued Accounting Standards not yet Adopted In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2014-09 which provides guidance on how an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the Entity expects to be entitled in exchange for those goods or services and on accounting for costs to obtain or fulfill a contract with a customer. The ASU also requires expanded disclosure regarding the nature, amount, timing and uncertainty of revenue that is recognized. In July 2015, the FASB decided to delay the effective date of this ASU by one year. This ASU, as amended, will be effective for the Company beginning in the first quarter of fiscal 2019 and can be adopted either full retrospective or modified retrospective with the cumulative effect recognized as of the date of adoption. Early adoption is permitted, but no earlier than fiscal 2018. We expect to adopt this ASU on a modified retrospective basis in the first quarter of fiscal 2019, and we are currently assessing the impact of this ASU on our consolidated financial statements. The FASB since issued additional updates of its new standard on revenue recognition issued in May 2014. In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606) - Principal versus Agent Considerations, which clarifies the implementation guidance for principal versus agent considerations in ASU 2014-09. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606) - Identifying Performance Obligations and Licensing, which amends the guidance in ASU 2014-09 related to identifying performance obligations and accounting for licenses of intellectual property. We are currently assessing the adoption and impact of these ASUs on our consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which modified lease accounting for both lessees and lessors to increase transparency and comparability by recognizing lease assets and lease liabilities by lessees for those leases classified as operating leases under previous accounting standards and disclosing key information about leasing arrangements. This ASU will be effective for the Company beginning in the first quarter of fiscal 2020 on a modified retrospective basis. Early adoption is permitted. We are currently evaluating the impact of adopting the new lease standard on our consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments -Credit Loses (Topic 326): Measurement of Credit Losses on Financial Instruments. The ASU requires measurement and recognition of expected credit losses for financial assets held based on historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. The ASU will be effective for the Company beginning in the first quarter of fiscal 2021 on a modified retrospective basis and early adoption in fiscal 2020 is permitted. We are currently assessing the timing of adoption and impact of these ASUs on our consolidated financial statements.

Acquisitions

Acquisitions	12 Months Ended
	Oct. 02, 2016
Business Combinations [Abstract]
Acquisitions	Note 2 Acquisitions and Divestitures On January 15, 2016 (the "Acquisition Date"), we acquired all outstanding shares of PMC, for $2.0 billion in cash and the issuance of approximately 16.0 million shares of Microsemi common stock and the assumption of certain PMC restricted stock units. The acquisition has provided Microsemi with a leading position in high performance and scalable storage solutions, while also adding a complementary portfolio of high-value communications products. A summary of the consideration for PMC is as follows (amounts in millions): Cash consideration $ 1,994.4 Share consideration 474.5 Assumption of equity awards 15.7 Accrued cash consideration 0.3 Total consideration $ 2,484.9 We recorded PMC's tangible and intangible assets and liabilities based on their estimated fair values as of the Acquisition Date and allocated the remaining purchase consideration to goodwill. The allocation is as follows (amounts in millions): Cash and cash equivalents $ 313.0 Accounts receivable 53.3 Inventories 98.2 Other current assets 15.8 Property and equipment 38.0 Other assets 19.7 Identifiable intangible assets 747.6 Goodwill 1,472.3 Deferred income taxes, net (87.3 ) Current liabilities (121.6 ) Other non-current liabilities (64.1 ) Total consideration $ 2,484.9 As of the Acquisition Date, the gross contractual amount of acquired accounts receivable of $53.3 million was expected to be fully collected. The valuation of identifiable intangible assets and their estimated useful lives are as follows (amounts in millions): Asset Amount Weighted Average Useful Life (Years) Completed technology $ 447.0 6 In-process research and development 241.0 Customer relationships 52.0 9 Other 7.6 1 $ 747.6 We utilized the straight line method of amortization for completed technology, customer relationships and other intangible assets. Valuation methodology The fair value of completed technology and in-process research and development ("IPR&D") was estimated by performing a discounted cash flow analysis using the multiperiod excess earnings approach. This method includes discounting the projected cash flows associated with each technology over its expected life. Projected cash flows attributable to the completed technology and IPR&D were discounted to their present value at a rate commensurate with the perceived risk. IPR&D consists of four main projects with expected completion dates of between six months and two years. Following a release date, expected useful lives are between five and eight years. The valuation of customer relationships was based on the distributor method, taking into account the profit margin a market participant distributor would obtain in selling PMC products. The useful lives of customer relationships are estimated based primarily upon customer turnover data. Other identifiable intangible assets consisted of backlog, valued using the distributor method, and trade name, valued using a relief from royalty method. Assumptions used in forecasting cash flows for each of the identified intangible assets included consideration of the following: • Historical performance including sales and profitability. • Business prospects and industry expectations. • Estimated economic life of asset. • Development of new technologies. • Acquisition of new customers. • Attrition of existing customers. • Obsolescence of technology over time. Depending on the structure of a particular acquisition, goodwill and identifiable intangible assets may not be deductible for tax purposes. We determined that goodwill and identifiable intangible assets related to the PMC acquisition are not deductible. The factors that contributed to a purchase price resulting in the recognition of goodwill include: • Our belief the merger will create a more diverse semiconductor company with expansive offerings which will enable us to expand our product offerings. • Our belief we are committed to improving cost structures in accordance with our operational and restructuring plans which should result in a realization of cost savings and an improvement of overall efficiencies. The purchase price allocation described above is preliminary, primarily with respect to tax contingency matters. Compared to our initial purchase price allocation, identifiable intangible assets increased by $2.0 million , current liabilities decreased by $17.6 million , other non-current liabilities increased by $3.6 million , deferred income taxes, net increased by $48.0 million , and purchase consideration increased by $9.5 million , with a corresponding adjustment to increased goodwill by $41.5 million . A final determination of fair values of assets acquired and liabilities assumed relating to the transaction could differ from the preliminary purchase price allocation. We utilize the straight line method of amortization for completed technology, customer relationships and trade name. Supplemental pro forma data (unaudited) The supplemental pro forma data presented is for illustrative purposes only and is not necessarily indicative of the financial position or results of operations that would have been realized if the transaction had been completed on the date indicated, does not reflect synergies that might have been achieved, nor is it indicative of future operating results or financial position. The pro forma adjustments are based upon currently available information and certain assumptions we believe are reasonable under the circumstances. The following supplemental pro forma data summarizes the results of operations for the periods presented, as if we completed the acquisition noted above as of the first day of 2015. The supplemental pro forma data reports actual operating results, adjusted to include the pro forma effect and timing of the impact in amortization expense of identified intangible assets, incremental interest expense and the related tax effects of the acquisition. In accordance with the pro forma acquisition date we recorded, in the 2015 supplemental pro forma data, cost of goods sold from manufacturing profit in acquired inventory of $66.2 million , PMC-related restructuring costs of $48.6 million and acquisition-related costs of $41.1 million , with a corresponding reduction in the 2016 supplemental pro forma data. Net sales related to products from the acquisition of PMC contributed approximately 20% to 25% of net sales for the year ended October 2, 2016. Post-acquisition net sales and earnings on a standalone basis are generally impracticable to determine as, on the acquisition date, we implemented a plan developed prior to the completion of the acquisition and began to immediately integrate the acquisition into existing operations, engineering groups, sales distribution networks and management structure. Supplemental pro forma data is as follows (amounts in millions): 2016 2015 Net sales $ 1,804.5 $ 1,773.9 Net income (loss) $ 82.3 $ (168.0 ) Earnings (loss) per share: Basic $ 0.74 $ (1.52 ) Diluted $ 0.72 $ (1.52 ) Divestitures On April 28, 2016, we divested our Remote Radio Head business to MaxLinear, Inc. for $21.0 million in cash. The Remote Radio Head business was operated as a non-strategic component of the enterprise storage and communications solution business. On May 2, 2016, we divested our membership interest in RF LLC to Mercury Systems, Inc. for $300.0 million in cash. RF LLC operated a non-strategic component of a board level systems and packaging business. These transactions resulted in a gain on divestiture of $125.5 million included in other income (expense), net in the Consolidated Statement of Operations and Comprehensive Income (Loss). As of October 2, 2016 , we recorded $13.9 million in assets held for sale on our consolidated balance sheet, which included $7.2 million of goodwill. The carrying amount of goodwill classified as assets held for sale was based on the relative fair value of the business expected to be divested and the remaining businesses retained as of October 2, 2016 . Acquisition and Divestiture Costs During the fiscal year ended October 2, 2016, we incurred $31.4 million in acquisition and divestiture costs related to the acquisition of PMC and divestitures of our Remote Radio Head business and RF LLC. These costs were recorded in selling, general and administrative expense.

Inventories

Inventories	12 Months Ended
	Oct. 02, 2016
Inventory Disclosure [Abstract]
Inventories	Note 3 Inventories Inventories consisted of the following components (amounts in millions): October 2, September 27, Raw materials $ 32.8 $ 56.5 Work in progress 112.8 111.7 Finished goods 67.5 59.0 $ 213.1 $ 227.2

Property and Equipment

Property and Equipment	12 Months Ended
	Oct. 02, 2016
Property, Plant and Equipment [Abstract]
Property and Equipment	Note 4 Property and Equipment Property and equipment consisted of the following components (dollar amounts in millions): Asset Life October 2, September 27, Buildings 20-40 years $ 37.2 $ 43.0 Machinery and equipment 3-10 years 439.3 429.1 Furniture and fixtures 5-10 years 8.9 9.8 Leasehold improvements Shorter of asset life or life of lease 62.6 54.1 548.0 536.0 Accumulated depreciation (382.2 ) (393.8 ) Land 1.5 1.9 Construction in progress 7.6 8.6 $ 174.9 $ 152.7 Depreciation expense was $46.1 million , $36.2 million and $32.9 million in 2016 , 2015 and 2014 , respectively.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, Net	12 Months Ended
	Oct. 02, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets, Net	Note 5 Goodwill and Intangible Assets, Net Goodwill and intangible assets, net consisted of the following components (dollar amounts in millions): October 2, 2016 September 27, 2015 Life (in years) Gross Accumulated Gross Accumulated Amortizable intangible assets Completed technology $ 907.7 $ (335.1 ) $ 489.7 $ (251.7 ) 2 to 15 Customer relationships 338.0 (219.2 ) 316.2 (197.1 ) 4 to 15 Backlog, trade name and other 24.9 (22.7 ) 18.8 (18.1 ) 1 to 5 $ 1,270.6 $ (577.0 ) $ 824.7 $ (466.9 ) Non-amortizable intangible assets Goodwill $ 2,479.4 $ 1,139.3 In-process research and development $ 241.0 $ — A reconciliation of our goodwill for the years ended October 2, 2016 and September 27, 2015 is as follows (amounts in millions): October 2, 2016 September 27, 2015 Beginning balance $ 1,139.3 $ 885.6 Additions from acquisitions 1,472.3 253.7 Reductions from divestitures (125.0 ) — Carrying value of goodwill classified as assets held for sale (7.2 ) — Ending balance $ 2,479.4 $ 1,139.3 Amortization of intangible assets included in operating expenses for each of the three fiscal years in the period ended October 2, 2016 is as follows (amounts in millions): 2016 2015 2014 Completed technology $ 108.7 $ 50.4 $ 43.9 Customer relationships 46.5 44.6 45.0 Backlog, trade name and other 6.0 1.5 3.9 $ 161.2 $ 96.5 $ 92.8 Estimated amortization expense in each of the five succeeding years and thereafter is as follows (amounts in millions): 2017 2018 2019 2020 2021 Thereafter $ 174.3 $ 130.7 $ 111.1 $ 105.8 $ 105.8 $ 65.7

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Oct. 02, 2016
Accounts Payable and Accrued Liabilities, Current [Abstract]
Accrued Liabilities	Note 6 Accrued Liabilities Accrued liabilities consisted of the following components (amounts in millions): October 2, September 27, Payroll, bonus and employee benefits $ 53.8 $ 33.3 Interest 31.2 — Licenses 26.0 6.0 Deferred revenue 15.1 9.7 Outside services 12.8 9.2 Warranties 7.5 6.4 Restructuring and severance 4.6 2.5 Commissions 4.3 3.8 Property and sales taxes 2.4 1.3 Leases and rent 2.5 2.6 Customer deposits 1.1 2.2 Other 4.8 9.8 $ 166.1 $ 86.8

Income Taxes

Income Taxes	12 Months Ended
	Oct. 02, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Note 7 Income Taxes Pretax income (loss) was generated from the following sources for each of the three fiscal years in the period ended October 2, 2016 (amounts in millions): 2016 2015 2014 Domestic $ (112.5 ) $ (14.9 ) $ (62.7 ) Foreign 87.1 111.8 86.6 Total $ (25.4 ) $ 96.9 $ 23.9 The provision for income taxes consisted of the following components for each of the three fiscal years in the period ended October 2, 2016 (amounts in millions): 2016 2015 2014 Current: State 0.2 0.2 0.3 Foreign 4.3 4.2 3.9 Deferred: Federal 4.1 4.6 (6.5 ) State 0.2 — (0.2 ) Foreign (1.6 ) 3.3 3.3 $ 7.2 $ 12.3 $ 0.8 We recorded a provision for income taxes of $7.2 million on pretax loss of $25.4 million in 2016 compared to a provision for income taxes of $12.3 million and $0.8 million on pre-tax income of $96.9 million and $23.9 million in 2015 and 2014, respectively. For each of these years, the provisions for income taxes were primarily due to the tax provision on profitable entities in foreign jurisdictions, U.S. tax provision relating to deferred tax liabilities that will not provide future sources of income to realize deferred tax assets, and release of valuation allowance due to additional deferred tax liabilities acquired through purchase accounting. We had cumulative operating losses for the three years ended in 2016 for our U.S. operations and several foreign operations and accordingly, have provided a full valuation allowance on certain of our U.S. and foreign net deferred tax assets as we have determined that it is more likely than not that the tax benefits will not be realized in the future. During 2016 and 2015, we increased the valuation allowance by $205.9 million and $31.6 million , respectively, which primarily related to increases in net deferred tax assets from current year activity that are not realizable and a net increase due to acquired deferred tax assets net of liabilities. During 2016, the increase was partially offset by a change in the expected realizability of certain deferred tax assets that previously had a full valuation allowance. We have federal and state net operating losses ("NOLs") of $671.7 million and $713.6 million , respectively, that both begin expiring in 2017. We have foreign NOLs of approximately $213.5 million that begin expiring in 2017. We have federal and state research and experimentation credits of $125.5 million and $111.2 million , respectively. We have foreign research and experimentation credits of approximately $139.6 million that begin expiring in 2017 and incentive deductions of $26.2 million that carry forward indefinitely. We have federal foreign tax credits of approximately $38.4 million that begin expiring in 2021. We have federal and state enterprise zone credits, federal and state investment tax credits, and alternative minimum tax credits totaling $9.0 million that begin expiring in 2017. We have federal and state capital loss carry forwards of $0.6 million that will begin expiring in 2019. The utilization of NOLs and credits acquired through an acquisition may be subject to limitations due to change in control. In December 2015, the U.S. government permanently reinstated the federal research and development tax credit retroactively to January 1, 2015. We are currently in a loss position for U.S. income tax purposes with a full valuation allowance; therefore, no benefit has been recognized for the period ended October 2, 2016 . We have been granted a tax holiday in our subsidiary in Malaysia that has the effect of reducing its net income tax rate to zero in that jurisdiction. The tax holiday was granted in 2009 and is effective through December 2019, subject to continued compliance with the tax holiday's requirements. No provision has been made for future income taxes on undistributed earnings of foreign operations (except for certain insignificant jurisdictions) since they have been indefinitely reinvested in these operations. Determination of the amount of unrecognized deferred tax liability for temporary differences related to these undistributed earnings is not practicable; as such liability is dependent upon a number of factors, including foreign tax credit position that would exist at the time any remittance would occur. At the end of 2016 and 2015, these undistributed earnings aggregated approximately $793.8 million and $471.2 million , respectively. The following is a reconciliation of income tax computed at the federal statutory rate to our actual tax expense for each of the three fiscal years in the period ended October 2, 2016 (amounts in millions): 2016 2015 2014 Tax computed at federal statutory rate $ (8.9 ) $ 33.9 $ 8.4 State taxes, net of federal impact 0.5 (2.1 ) (1.1 ) Foreign income taxed at different rates (7.0 ) (33.1 ) (24.7 ) Tax credits and incentives (10.7 ) (5.1 ) (2.8 ) Stock award compensation (4.6 ) 1.3 1.2 Unrecognized tax benefits 30.6 3.7 1.4 Sale/transfer of assets (45.6 ) — — U.S. tax on foreign income 2.0 1.3 4.1 Non-deductible permanent items 6.2 0.9 0.9 Pre-acquisition loss carry forwards — — (11.4 ) Expiration of tax attributes 5.0 — 2.9 Investment in foreign subsidiaries 2.7 (0.5 ) 3.6 Withholding taxes 1.1 (0.3 ) 0.3 Other differences, net 0.6 (1.0 ) 0.4 Valuation allowance 35.3 13.3 17.6 $ 7.2 $ 12.3 $ 0.8 The tax effected deferred tax assets (liabilities) are comprised of the following components (amounts in millions): October 2, September 27, 2015 Accounts receivable, net $ 2.1 $ 1.9 Inventories 18.8 17.5 Accrued employee benefit expenses 10.0 8.4 Net operating losses 216.1 164.6 Tax credits and incentives 238.0 153.5 Accrued other expenses 10.3 9.7 Deferred equity compensation 20.0 18.9 Property and equipment, net 4.4 13.8 Debt issuance costs 20.9 0.3 Other assets 12.3 11.1 Total deferred tax assets 552.9 399.7 Intangible assets (176.8 ) (137.1 ) Investment in foreign subsidiaries (2.5 ) — Total deferred tax liabilities (179.3 ) (137.1 ) Less valuation allowance (456.4 ) (250.6 ) $ (82.8 ) $ 12.0 A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (amounts in millions): October 2, September 27, September 28, 2014 Beginning gross unrecognized tax benefits $ 121.8 $ 97.7 $ 69.6 Additions based on tax positions related to the current year 33.1 3.5 2.4 Additions based on current year acquisitions 132.6 16.2 28.9 Additions based on tax positions of prior years 36.3 4.8 0.4 Reductions for lapses and settlements (4.8 ) (0.4 ) (3.6 ) Ending gross unrecognized tax benefit $ 319.0 $ 121.8 $ 97.7 We recognize interest and penalties accrued related to unrecognized tax benefits in tax expense. During the years ended October 2, 2016 , September 27, 2015 , and September 28, 2014 , we recognized $3.7 million , $0.7 million and $0.7 million , respectively in interest and penalties. The cumulative interest and penalties at October 2, 2016 and September 27, 2015 were $42.0 million and $7.4 million , respectively. Unrecognized tax benefits of $114.9 million (including interest) at October 2, 2016 would impact the effective tax rate if recognized after the valuation allowance has been released. We anticipate a decrease in gross unrecognized tax benefits of approximately $17.2 million within the next twelve months based on federal, state, and foreign expirations in various jurisdictions. We file U.S. federal, state, and foreign income tax returns in jurisdictions with varying statutes of limitations. Fiscal years 2007 to 2015 generally remain subject to examination by federal and most state tax authorities. In significant foreign jurisdictions, the 2007 to 2015 tax years generally remain subject to examination by tax authorities. We establish liabilities for possible assessments by tax authorities resulting from known tax exposures including, but not limited to, international tax issues and certain tax credits. The Internal Revenue Service is currently examining our income tax returns for tax years 2007 through 2014 and the Canada Revenue Agency is currently examining income tax returns assumed from the PMC acquisition for tax years 2007 through 2014. Both examinations primarily relate to transfer pricing matters. Management believes that our position is appropriate and that an adequate provision has been made for any adjustments that may result from tax examinations. However, the outcome of tax audits cannot be predicted with certainty. If any issues addressed in our tax audits are resolved in a manner not consistent with management's expectations, we would be required to adjust our provision for income tax in the period such resolution occurs. While we believe our reported results are appropriate, any significant adjustments could have a material adverse effect on our results of operations, cash flows and financial position if not resolved within management expectations.

Debt

Debt	12 Months Ended
	Oct. 02, 2016
Debt Disclosure [Abstract]
Credit Agreement	Note 8 Debt Credit Agreement On January 15, 2016, we entered into a Credit Agreement (as amended, the "Credit Agreement") with Morgan Stanley Senior Funding, Inc. ("MSSF"), as administrative agent and collateral agent, the other agents party thereto and the lenders referred to therein (collectively, the "Lenders"). The Lenders provided $2.5 billion senior secured first lien credit facilities (collectively, as amended, the "Credit Facilities"), consisting of a term A loan facility (as amended, the "Term Loan A Facility") in an aggregate principal amount of $450.0 million , a term B loan facility (as amended, the "Term Loan B Facility") in an aggregate principal amount of $1.7 billion and a revolving credit facility (the "Revolving Facility") with commitments in an aggregate principal amount of $325.0 million . The Credit Facilities financed a portion of the acquisition of PMC and fees and expenses related thereto. The Revolving Facility is also available for working capital requirements and other general corporate purposes. Refinancing of Credit Agreement On June 29, 2016, we entered into an Increase Term Joinder to the Credit Agreement with respect to an incremental Term Loan A Facility in an aggregate principal amount of $364.3 million under our existing Credit Agreement. We used the total proceeds to pay down a portion of our Term Loan B Facility. In addition, on June 29, 2016, we entered into Amendment No. 1 to our existing Credit Agreement (together with the Increase Term Joinder, the "First Amendment"). The First Amendment provided for, among other things, (i) new pricing terms for the outstanding Term B Loan Facility in the aggregate original principal amount, (ii) certain modifications to the repricing event prepayment provisions and (iii) certain other modifications to facilitate restructuring of our subsidiaries. The Credit Facilities bear interest, at our option, at Base Rate or LIBOR, plus a margin. The margin for borrowings under the Term Loan A Facility and Revolving Facility vary depending upon our consolidated net leverage ratio. At October 2, 2016 , all principal amounts outstanding were Eurodollar Rate loans and interest rate information were as follows: Principal Outstanding Base Rate Base Rate Margin Eurodollar Rate Margin Eurodollar Floor Applicable Rate Revolving and swingline loans $ 275.0 3.50 % 1.25 % 2.25 % — % 2.77 % Term A loan $ 798.5 3.50 % 1.25 % 2.25 % — % 2.77 % Term B loan $ 699.7 3.50 % 2.00 % 3.00 % 0.75 % 3.75 % The Credit Agreement also requires us to pay a commitment fee for the unused portion of the Revolving Facility, which will be a minimum of 0.25% and a maximum of 0.35% , depending on the Company’s consolidated net leverage ratio. Interest for Base Rate loans is calculated on the basis of a 365/366-day year and interest for LIBOR-based loans is calculated on the basis of a 360-day year. Subject to certain customary exceptions, all of our obligations under the Credit Facilities are unconditionally guaranteed by each of our existing and subsequently acquired or organized direct and indirect wholly-owned domestic subsidiaries whose assets or revenues exceed 5% of the consolidated assets or revenues, as the case may be, of Microsemi and its subsidiaries (the "Guarantors"). Other domestic subsidiaries will be required to become a Guarantor to the extent that domestic subsidiaries excluded from such guarantee obligation represent, in the aggregate, more than 15% of the consolidated assets and more than 15% of the consolidated gross revenues of Microsemi. The obligations under the Credit Facilities are our and the Guarantors’ senior secured obligations collateralized by a lien on substantially all of our personal property and material real property assets, subject in each case to certain customary exceptions (collectively, the "Collateral"). The Term Loan A Facility matures January 15, 2021. The Term Loan A Facility requires quarterly principal payments of 1.25% of the amended principal amount for the first two years following the closing date and 2.5% of the amended principal amount for the remaining term. The Term Loan B Facility matures on January 15, 2023. The Term Loan B Facility requires quarterly principal payments equal to 0.25% of the original principal amount of the Term Loan B Facility. We have made optional principal payments on our Term Loan B Facility such that there are no scheduled principal payments until maturity. Additionally, the Credit Agreement stipulates an annual principal payment of a percentage of Excess Cash Flow ("ECF") (as defined in the Credit Agreement) to repay the Term Loan B Facility. The first ECF application date will be measured as of the end of fiscal year 2017 and the ECF percentage is expected to be 50% if the consolidated net leverage ratio as of the last day of the fiscal year is greater than 3.00 to 1.00, 25% if the consolidated net leverage ratio as of the last day of the fiscal year is less than or equal to 3.00 to 1.00 but greater than 2.50 to 1.00 and 0% otherwise. Our Credit Agreement contains financial covenants including a maximum consolidated net leverage ratio and minimum fixed charge coverage ratio and also contains other customary affirmative and negative covenants and events of default. We were in compliance with our covenants as of October 2, 2016 . Senior Unsecured Notes On January 15, 2016, we completed the sale of $450.0 million of our 9.125% senior unsecured notes due April 2023 to qualified institutional buyers and pursuant to Regulation S in a private offering exempt from the registration requirements of the Securities Act of 1933, as amended. The Notes were issued under an indenture, dated January 15, 2016, among Microsemi, the subsidiaries of Microsemi party thereto as note guarantors (the "Note Guarantors"), and U.S. Bank National Association, as trustee (the "Indenture"). The Notes accrue cash interest at a rate of 9.125% per year, payable semi-annually on April 15 and October 15 of each year. The Notes mature on April 15, 2023. We may redeem the Notes, and the holders of the Notes may require us to repurchase the Notes, prior to this date of maturity in certain circumstances pursuant to the terms and conditions of the Indenture. The Indenture contains customary affirmative and negative covenants and events of default. The Notes are our general senior unsecured obligations and rank equal in right of payment with all of our existing and future senior unsecured obligations, are senior in right of payment to all of our future subordinated indebtedness, if any, are structurally subordinated to all of our existing and future obligations, claims of holders of preferred stock and other liabilities of our subsidiaries that do not guarantee the Notes and are effectively subordinated in right of payment to all of our senior secured indebtedness (including our obligations under the Credit Facilities) to the extent of the value of the assets securing such obligations. The Notes are unconditionally guaranteed, jointly and severally, on a senior unsecured basis by all of our subsidiaries that guarantee the Credit Agreement. Each guarantee of the Notes is the general senior unsecured obligation of the Note Guarantors and is effectively subordinated to the senior secured obligations of the Note Guarantors (including the Note Guarantors’ obligations under the Credit Facilities) to the extent of the value of the assets securing such obligations, are equal in right of payment to all existing and future unsecured obligations of the Note Guarantors that are not, by their terms, expressly subordinated in right of payment to the Notes and rank senior in right of payment to all future obligations, if any, of the Note Guarantors that are by their terms, expressly subordinated in right of payment to the guarantees. Fair Value of Debt As of October 2, 2016 , the fair value of principal outstanding on the Credit Facilities and Senior Unsecured Notes were as follows (amounts in millions): Principal outstanding Fair value Credit Facilities $ 1,773.2 $ 1,772.1 Senior Unsecured Notes 450.0 513.0 Total debt $ 2,223.2 $ 2,285.1 Debt Extinguishment, Modification, and Issuance Costs On January 15, 2016, concurrent with entering into the Credit Agreement, we terminated our senior secured credit agreement with Bank of America, N.A., which included a term loan A facility and a revolving facility maturing on August 19, 2019 and a term loan B facility maturing on February 19, 2020 (the "2011 Credit Agreement"). We accounted for this termination as debt extinguishment. In addition, we accounted for the refinancing of our Term Loan A Facility and Term Loan B Facility pursuant to the First Amendment as a debt modification with respect to amounts that remained in the syndicate and debt extinguishment with respect to the amounts that exited the syndicate. During the second quarter of 2016, we paid financing fees related to the Credit Agreement of $112.2 million which was recorded in cash flows from financing activities. We recorded a debt extinguishment charge of $72.3 million consisting of $61.3 million in fees paid during the second quarter which was recorded in cash flows from financing activities and $11.0 million of deferred financing fees from the 2011 Credit Agreement. During the third quarter of 2016, we paid financing fees related to the First Amendment of $19.1 million , of which $16.1 million was accounted for as debt modification fees was recorded in cash flow from operating activities and $3.0 million was accounted for as debt extinguishment fees was recorded in cash flows from financing activities. We recorded a debt extinguishment charge of $4.5 million as an allocation of credit facility fees to parties exiting the Credit Agreement. We reported debt extinguishment charges in other expense, net in our Consolidated Statement of Operations and Comprehensive Income (Loss). Debt issuance costs recorded as a reduction to principal outstanding in the condensed consolidated balance sheets were $44.0 million as of October 2, 2016 and $11.7 million as of September 27, 2015 .

Other Long-Term Liabilities

Other Long-Term Liabilities	12 Months Ended
	Oct. 02, 2016
Other Liabilities Disclosure [Abstract]
Other Long-Term Liabilities	Note 9 Other Long-Term Liabilities Other long-term liabilities consisted of (amounts in millions): October 2, September 27, Unrecognized tax benefits $ 70.6 $ 19.8 Deferred rent 17.2 11.2 Pension and retirement 14.2 8.9 Restructuring 4.2 3.4 Other 9.6 3.0 Total $ 115.8 $ 46.3

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Oct. 02, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Note 10 Stock-Based Compensation Stock Based Compensation In February 2016, our stockholders approved amendments to the Microsemi Corporation 2008 Performance Incentive Plan (the "2008 Plan"). The amendments a) increased the share limit by an additional approximately 4.8 million shares so that the amended aggregate share limit for the 2008 Plan is approximately 41.8 million shares; b) extended the term of the 2008 Plan to December 2, 2025; c) limited the grant date value of awards that may be granted to non-employee directors under the 2008 Plan during any one calendar year to $0.4 million (or $0.6 million as to any newly elected or appointed non-employee director or a non-employee director serving as chairman of the Board or lead independent director); and d) extended the Company's authority to grant awards under the 2008 Plan intended to qualify as "performance-based awards" within the meaning of Section 162(m) of the U.S. Internal Revenue Code through the first annual meeting of stockholders that occurs in 2021. For every one share issued in connection with a full value award (such as a restricted stock award, and as defined in the 2008 Plan), 2.41 shares will be counted against the share limit. Except as described in this paragraph, shares that are subject to or underlie awards which expire or for any reason, are canceled or terminated, are forfeited, fail to vest, or for any other reason are not paid or delivered under the 2008 Plan will again be available for subsequent awards under the 2008 Plan. Shares exchanged by a participant or withheld by the Company as full or partial payment in connection with any award granted under the 2008 Plan that is a full-value award, as well as any shares exchanged by a participant or withheld by the Company or one of its subsidiaries to satisfy the tax withholding obligations related to any full-value award granted under the 2008 Plan will be available for subsequent awards under the 2008 Plan. Shares exchanged by a participant or withheld by the Company to pay the exercise price of a stock option or stock appreciation right granted under the 2008 Plan, as well as any shares exchanged or withheld to satisfy the tax withholding obligations related to any such award, will not be available for subsequent awards under the 2008 Plan. Tax withholding obligations are established at the statutory minimum requirements for any shares exchanged or withheld. Awards authorized by the 2008 Plan include options, stock appreciation rights, restricted stock, stock bonuses, stock units, performance share awards, and other cash or share-based awards. The shares issued under the 2008 Plan may be newly issued or shares held by Microsemi as treasury stock. The maximum term of a stock option grant or a stock appreciation right granted under the 2008 Plan is 6 years . Stock-based compensation expense was $101.1 million in 2016 , of which, $23.1 million was recorded in restructuring expense. Stock-based compensation expense was $49.8 million and $43.9 million in 2015 and 2014 , respectively. At October 2, 2016 , unamortized compensation expense related to unvested stock awards was $102.3 million . The weighted average period over which compensation expense related to these grants will be recognized is 1.5 years . Remaining share-units available for grant, assuming the issuance of performance units at target, at October 2, 2016 , September 27, 2015 and September 28, 2014 under the 2008 Plan were 12.3 million , 11.7 million and 14.1 million , respectively. Restricted Shares Compensation expense for restricted shares was calculated based on the closing price of our common stock on the date of grant and the restricted shares are subject to forfeiture if a participant does not meet length of service requirements. Restricted stock awards granted to employees typically vest over a three year period and awards granted to non-employee directors vest in accordance with our director compensation policy. Activity and price information related to restricted stock awards are as follows (quantity in millions): Quantity Weighted-Average Grant Price Outstanding at September 29, 2013 3.1 Granted 1.6 $ 24.67 Vested (1.4 ) Forfeited (0.2 ) Outstanding at September 28, 2014 3.1 Assumed from acquisition 0.3 $ 33.01 Granted 1.3 $ 29.37 Vested (1.5 ) Forfeited (0.2 ) Outstanding at September 27, 2015 3.0 Assumed from acquisition 1.9 $ 29.77 Granted 1.3 $ 32.15 Vested (2.1 ) Forfeited (0.5 ) Outstanding at October 2, 2016 3.6 In connection with the acquisition of Vitesse in 2015 and PMC in 2016, we assumed restricted shares and converted them to Microsemi awards in accordance with the merger agreements. Stock Units with Performance and Market Conditions Compensation expense for performance stock units with performance and market conditions was calculated based upon expected achievement of the performance metrics specified in the grant and the closing price of our common stock on the date of grant, or when a grant contains a market condition, the grant date fair value using a Monte Carlo simulation which incorporates estimates of the potential outcomes of the market condition on the fair value date of each award. Performance units with performance and market conditions are eligible to vest based on our rate of growth for net sales and earnings per share (subject to certain adjustments) relative to the growth rates for that metric over the relevant performance period for a peer group of companies. The performance period for each grant is over three fiscal years and portion of the performance units may vest based on performance after each fiscal year of the performance period. For the 2014 grants, 40% of each performance-based award opportunity will be subject to the net sales metric for the performance period and 60% will be subject to the earnings per share metric for the performance period. The maximum percentage for a particular metric is 200% of the "target" number of units subject to the award related to that metric. For the 2015 grant, 70% of each performance-based award opportunity will be subject to the net sales metric for the performance period and 30% will be subject to the earnings per share metric for the performance period. The maximum percentage for a particular metric is 225% of the "target" number of units subject to the award related to that metric. The maximum percentage is further adjusted by our total shareholder return relative to a peer group selected by the Compensation Committee. For the 2014 grant, the maximum adjustment is 125% and for the 2015 and 2016 grant, the maximum adjustment is 120% . Stock Units with Market Conditions In July 2016, the Compensation Committee (the “Committee”) of the Board of Directors of the Company approved a long-term incentive equity award for our chief executive officer consisting of 1,000,000 restricted stock units awarded under the Company’s 2008 Plan. Under the award agreement, the vesting of the RSUs is contingent on the Company’s stock price achieving specified levels during the five -year period after the date of grant of the award (the “performance period”) as follows: Stock Price Level Percentage of Total Award That Vests $50.00 25% $60.00 50% $70.00 25% For a stock price level to be considered achieved, the closing price of the Company’s common stock (together with any dividends paid on a share of the Company’s stock after the grant date of the award) must equal or exceed that level for a period of at least 20 consecutive trading days. A stock price level will also be considered achieved if, during the performance period, a change in control of the Company occurs after which the Company does not survive as a public company (a “Sale of the Company”) and the per-share price of the Company’s common stock in the Sale of the Company (together with any dividends paid on a share of the Company’s stock after the grant date of the award) equals or exceeds that level. In each case, the vesting of the award is subject to Mr. Peterson’s continued employment with the Company through the date the applicable stock price level is met. The award is also eligible to vest in connection with certain “acceleration events” as described below. If, during the first year of the performance period, an acceleration event occurs and the award has not yet vested as to at least 160,000 RSUs, the award will accelerate on the event to the extent necessary so that 160,000 RSUs are vested on the event. If an acceleration event occurs during the performance period but after the first year of the performance period and the award has not yet vested as to at least 320,000 RSUs, the award will generally accelerate on the occurrence of the event to the extent necessary so that 320,000 RSUs are vested upon such event. If, however, an acceleration event occurs during the performance period but after the first year of the performance period, and the award has not yet vested as to at least 500,000 RSUs and the average closing price of the Company’s common stock for the period of 20 consecutive trading days ending with the date of the acceleration event (or, in the case of an acceleration event that is a Sale of the Company, the per-share sale price of the Company’s stock, and in each case together with any dividends paid on a share of the Company’s stock after the grant date) equals or exceeds $ 50.00 , the award will accelerate on occurrence of the event to the extent necessary so that 500,000 RSUs are vested upon such event. For these purposes, an “acceleration event” is either a change in control of the Company (whether or not the transaction constitutes a Sale of the Company) or a termination of our chief executive officer's employment by the Company without cause, by our chief executive officer for good reason or as a result of our chief executive officer's death or disability (as such terms are defined in the award agreement). In no event will the award vest as to more than 100% of the RSUs subject to the award (with the RSUs under the award being subject in each case to customary adjustments for stock splits and similar events). Activity and price information related to performance units are as follows (quantity reported at target and in millions): Quantity Outstanding at September 29, 2013 0.6 Granted 0.4 Vested (0.3 ) Outstanding at September 28, 2014 0.7 Granted 0.3 Vested (0.3 ) Outstanding at September 27, 2015 0.7 Granted 1.5 Vested (0.5 ) Outstanding at October 2, 2016 1.7 Stock Options and Stock Appreciation Rights Compensation expense for stock options and stock appreciation rights was calculated based on the grant or assumption date using the Black-Scholes pricing model. All stock appreciation rights we have granted or assumed are stock-settled. Stock options and stock appreciation rights are granted at exercise prices equal to the closing price of our common stock on the date of grant. Assumed stock options and stock appreciation rights are granted at exercise prices determined in accordance with the applicable merger agreement. Expected life and forfeiture rates were estimated based primarily on historical data that were stratified between members of the Board of Directors, executive employees and all other recipients. Expected volatility was estimated based on historical volatility using equally weighted daily price observations over a period approximately equal to the expected life of each option. The risk free interest rate is based on the implied yield currently available on U.S. Treasury securities with an equivalent remaining term. No dividends are expected to be paid. Activity and price information related to stock options and stock appreciation rights are as follows (quantity and intrinsic value in millions): Quantity Weighted-Average Exercise Price Intrinsic Value Weighted Average Remaining Life (Years) Outstanding at September 29, 2013 4.7 $ 22.49 $ 14.7 1.7 Assumed from acquisition 0.6 $ 20.08 Exercised (1.2 ) $ 16.39 $ 17.0 Forfeited (1.4 ) $ 26.55 Outstanding at September 28, 2014 2.7 $ 22.70 $ 7.4 2.0 Assumed from acquisition 0.2 $ 24.18 Exercised (2.1 ) $ 23.83 $ 15.8 Forfeited (0.1 ) $ 23.90 Outstanding at September 27, 2015 0.7 $ 19.60 $ 9.1 4.0 Exercised (0.2 ) $ 21.16 Forfeited — $ 21.44 Outstanding at October 2, 2016 0.5 $ 18.75 $ 10.7 3.5 Exercisable at October 2, 2016 0.4 $ 18.24 $ 9.8 3.3 Exercisable and expected to vest after October 2, 2016 0.5 $ 18.75 $ 10.7 3.5 In connection with the acquisitions Symmetricom, Inc. in 2014 and Vitesse in 2015, we assumed stock options and converted them to Microsemi awards in accordance with their respective merger agreements. Quantity and weighted-average exercise prices related to stock options and stock appreciation rights outstanding as of October 2, 2016 and stratified by exercise price are as follows (quantity in millions): Exercisable Outstanding Exercise Price Quantity Weighted-Average Exercise Price Quantity Weighted-Average Exercise Price Less than or equal to $20.00 0.3 $ 14.08 0.3 $ 14.17 Greater than $20.00 0.1 $ 25.87 0.2 $ 25.60 0.4 $ 18.24 0.5 $ 18.75

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Oct. 02, 2016
Postemployment Benefits [Abstract]
Employee Benefit Plans	Note 11 Employee Benefit Plans We sponsor 401(k) savings plans whereby participating employees may elect to contribute up to 50% of their eligible wages up to the statutory contribution limit. Employees 50 years of age and older may contribute a further 75% of their eligible wages up to the statutory contribution limit. During 2016 , employer contributions were $4.4 million . In certain entities outside the United States, we provide defined-benefit and defined contribution plans, many in accordance with local regulations. We typically deposit employer contributions with third party trustees, insurance trust funds, or government-managed accounts. We assumed pension plans in Germany related to an acquisition in 2012 and an acquisition in 2016 that covers certain German employees with over ten years of active service and provides benefits based on length of service and final pensionable earnings. There are no segregated pension fund assets under either of the plans assumed. The 2012 pension liability is insured and we have pledged the insurance contracts to the pensioners. Accordingly, the contracts are now considered to be a plan asset. As the plan assets are insurance contracts, the Company does not control the investment strategy and thus cannot influence the return on investments. The insurance payments are guaranteed by the insurer and should the insurer default on its obligation, the security fund for insurance companies in Germany would assume the contracts. The 2016 pension liability is not insured. As of October 2, 2016 , the fair value of the pension plan assets from the 2012 acquisition was $4.1 million and the fair value of the pension plan benefit obligations from 2012 and 2016 acquisitions were $6.9 million and $4.2 million , respectively. During 2016, we recorded an unrealized actuarial loss on pension benefits of $3.9 million in other comprehensive income due to a reduction in the discount rate assumption used to determine benefit obligations from 2.1% to 1.0% and 2.8% to 1.6% from the 2012 and 2016 acquisitions respectively. There are no employer contributions expected in the next twelve months.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Oct. 02, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 12 Commitments and Contingencies Operating Leases We occupy premises and lease equipment under operating lease agreements expiring through 2029. The aggregate undiscounted future minimum rental payments under these leases are as follows (amounts in millions): 2017 2018 2019 2020 2021 Thereafter $ 26.4 $ 24.0 $ 20.7 $ 17.8 $ 11.5 $ 16.7 Lease expense charged to income was $23.7 million in 2016 , $21.5 million in 2015 and $23.5 million in 2014 . Contingencies We are generally self-insured for losses and liabilities related to workers’ compensation and employer’s liability insurance. Accrued workers’ compensation liability was $1.7 million and $2.3 million at October 2, 2016 and September 27, 2015 , respectively. Our self-insurance accruals are based on estimates and, while we believe the amounts accrued are adequate, the ultimate claims may be in excess of the amounts provided. We are involved in pending litigation, administrative and similar matters arising out of the normal conduct of our business, including litigation relating to acquisitions, employment matters, commercial transactions, contracts, environmental matters and matters related to compliance with governmental regulations. The ultimate aggregate amount of monetary liability or financial impact with respect to these matters is subject to many uncertainties and is therefore not predictable with assurance. In the opinion of management, the final outcome of these matters, if they are adverse, will not have a material adverse effect on our financial position, results of operations or cash flows. However, there can be no assurance with respect to such result, and monetary liability, financial impact or other sanctions imposed on us from these matters could differ materially from those projected.

Restructuring and Severance Cha

Restructuring and Severance Charges	12 Months Ended
	Oct. 02, 2016
Restructuring and Related Activities [Abstract]
Restructuring and Severance Charges	Note 13 Restructuring and Severance Charges The following table reflects the related restructuring activities and the accrued liabilities at the dates below (amounts in millions): Employee Severance Contract Termination Costs Other Associated Costs Total Balance at September 27, 2015 $ 2.9 $ 3.2 $ 0.1 $ 6.2 Assumed from acquisition 2.9 — 0.1 3.0 Provisions 55.4 5.1 4.2 64.7 Reversal of prior provision (3.4 ) (0.3 ) (0.2 ) (3.9 ) Cash expenditures (32.4 ) (2.9 ) (0.9 ) (36.2 ) Other non-cash settlement (22.9 ) (0.5 ) (2.9 ) (26.3 ) Balance at October 2, 2016 $ 2.5 $ 4.6 $ 0.4 $ 7.5 We recorded net provisions for employee severance of $52.0 million for 2016 , of which $45.6 million directly related to the acquisition and integration of PMC. The non-cash settlement of employee severance relates to the acceleration of restricted stock awards in connection with the acquisition of PMC. Employee severance covered individuals in engineering, manufacturing, administration and sales and is expected to be paid within the next twelve months. We recorded provisions for contract termination costs of $5.1 million for 2016 , primarily for the fair value at the cease-use date of operating lease liabilities for space we have exited. Facilities consisted primarily of sales, engineering and administrative space, as well as manufacturing space. We recorded a $0.3 million reversal of prior provision related to a facility lease termination that was settled at an amount less than estimated. We recorded net provisions for other associated costs for restructuring of $4.0 million for 2016 , which consisted of facility and equipment impairments and facility relocation costs.

Segment Information

Segment Information	12 Months Ended
	Oct. 02, 2016
Segment Reporting [Abstract]
Segment Information	Note 14 Segment Information We manage our business on the basis of one reportable segment, as a manufacturer of semiconductors in different geographic areas, including the United States, Europe and Asia. We derive revenue from sales of our high-performance analog/mixed-signal ICs and power and high-reliability individual component semiconductors. These products include individual components as well as IC solutions that enhance customer designs by improving performance, reliability and battery optimization, reducing size or protecting circuits. The principal markets we serve include Aerospace & Defense, Communications, Data Center, and Industrial. We evaluate sales by end-market based on our understanding of end market uses of our products. Net sales based on a customer's ship-to location and by estimated end market are as follows (amounts in millions): 2016 2015 2014 United States $ 628.2 $ 610.0 $ 604.4 Europe 222.8 189.8 163.7 Asia 749.2 399.7 338.4 Other 54.8 46.1 31.8 Total $ 1,655.0 $ 1,245.6 $ 1,138.3 Aerospace & Defense $ 495.4 $ 527.2 $ 472.3 Communications 618.0 439.8 401.0 Data Center 276.9 11.9 6.6 Industrial 264.7 266.7 258.4 Total $ 1,655.0 $ 1,245.6 $ 1,138.3 As a percentage of consolidated net sales, customers with a ship-to location in Hong Kong totaled 18% in 2016 and 12% in 2015. There were no countries outside the United States exceeding 10% in 2014. The geographic location of distributors and third-party manufacturing service providers may be different from the geographic location of the ultimate end users. We believe a substantial portion of the products billed to these customers are ultimately shipped to end markets in the United States and Europe. Property and equipment, net by geographic area are as follows (amounts in millions): 2016 2015 2014 United States $ 119.2 $ 117.6 $ 117.9 Europe 16.4 13.9 12.2 Asia 22.6 18.9 16.8 Other 16.7 2.3 1.8 Total $ 174.9 $ 152.7 $ 148.7

Unaudited Selected Quarterly Fi

Unaudited Selected Quarterly Financial Data	12 Months Ended
	Oct. 02, 2016
Quarterly Financial Information Disclosure [Abstract]
Unaudited Selected Quarterly Financial Data	Note 15 Unaudited Selected Quarterly Financial Data Selected quarterly financial data are as follows (amounts in millions, except earnings (loss) per share): Quarters ended in fiscal year 2016 October 2, July 3, April 3, January 3, Net sales $ 450.1 $ 431.4 $ 444.3 $ 329.2 Cost of sales (excluding amortization of intangible assets) $ 168.3 $ 164.5 $ 243.7 $ 141.4 Gross profit $ 281.8 $ 266.9 $ 200.6 $ 187.8 Net income (loss) $ 40.5 $ 115.2 $ (212.0 ) $ 23.7 Basic earnings (loss) per share $ 0.36 $ 1.03 $ (1.93 ) $ 0.25 Diluted earnings (loss) per share $ 0.35 $ 1.00 $ (1.93 ) $ 0.25 Quarters ended in fiscal year 2015 September 27, June 28, March 29, December 28, Net sales $ 328.8 $ 317.1 $ 296.2 $ 303.5 Cost of sales (excluding amortization of intangible assets) $ 154.0 $ 145.0 $ 126.9 $ 135.4 Gross profit $ 174.8 $ 172.1 $ 169.3 $ 168.1 Net income $ 25.3 $ 14.7 $ 24.9 $ 19.7 Basic earnings per share $ 0.27 $ 0.16 $ 0.26 $ 0.21 Diluted earnings per share $ 0.26 $ 0.15 $ 0.26 $ 0.21

VALUATION AND QUALIFYING ACCOUN

VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Oct. 02, 2016
Valuation and Qualifying Accounts [Abstract]
VALUATION AND QUALIFYING ACCOUNTS	SCHEDULE II — VALUATION AND QUALIFYING ACCOUNTS (amounts in millions) Column A Column B Column C Column D Column E Column F Classification Balance at Charged Charged Deductions- Balance Accounts receivable allowance September 28, 2014 $ 17.8 $ 3.1 $ 1.3 $ — $ 22.2 September 27, 2015 $ 22.2 $ 3.1 $ 0.7 $ — $ 26.0 October 2, 2016 $ 26.0 $ 9.0 $ 6.7 $ — $ 41.7 Tax valuation allowance September 28, 2014 $ 210.1 $ 17.6 $ (8.8 ) $ — $ 218.9 September 27, 2015 $ 218.9 $ 13.3 $ 18.4 $ — $ 250.6 October 2, 2016 $ 250.6 $ 35.3 $ 170.5 $ — $ 456.4

Description of business and s23

Description of business and summary of significant accounting policies (Policies)	12 Months Ended
	Oct. 02, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principles of Consolidation and Presentation of Financial Information	The consolidated financial statements include the accounts of Microsemi and our subsidiaries. All intercompany transactions and balances have been eliminated.
Use of Estimates	The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the respective reporting periods. Actual results could differ from those estimates.
Cash and Cash Equivalents	We consider all short-term, highly liquid investments with an original maturity of three months or less to be cash equivalents.
Accounts Receivable and Allowance for Doubtful Accounts	Trade accounts receivable are recorded at the invoiced amount and do not bear interest. The accounts receivable amount shown in the balance sheet are trade accounts receivable balances at the respective dates, net of allowance for doubtful accounts. The allowance for doubtful accounts is our best estimate of the amount of probable credit losses in our existing accounts receivable. We determine the allowance based in part on our historical write-off experience and specific review of account balances due. Past due balances are reviewed individually for collectability. All other balances are reviewed on a pooled basis by the age of the receivable. Account balances are charged off against the allowance when we determine it is probable the receivable will not be recovered. We review our allowance for doubtful accounts quarterly. We do not have any off-balance-sheet credit exposure related to our customers. To date, our allowance for doubtful accounts has generally been within management’s estimates.
Inventories	Inventories are stated at the lower of cost, as determined using the first-in, first-out method, or market. Costs include materials, labor and manufacturing overhead. We evaluate the carrying value of our inventories taking into account such factors as historical and anticipated future sales compared with quantities on hand and the price we expect to obtain for our products in their respective markets. We also evaluate the composition of our inventories to identify any slow-moving, excess or obsolete products. Additionally, inventory write-downs are made based upon such judgments for any inventories that are identified as having a net realizable value less than their cost, which is further reduced by related selling expenses. The net realizable value of our inventories for ongoing operations has generally been within management’s estimates. We have recorded inventory write-downs for discontinued product lines that did not meet gross margin targets, products that are being migrated to newer generations, products that service the large capital spending end markets for which demand has declined, and products related to facility closures.
Fair Value of Financial Assets and Liabilities	Accounting Standards Codification ("ASC") 825 permits entities to elect the fair value option for certain financial assets and financial liabilities. For financial assets or financial liabilities for which an entity elects the fair value option, ASC 825 requires the entity record the financial asset or financial liability at fair value rather than at historical cost with changes in fair value recorded in the income statement. ASC 825-25 requires upfront costs and fees related to items for which the fair value option is elected shall be recognized in earnings as incurred and not deferred. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. ASC 820 establishes a hierarchy for ranking the quality and reliability of the information used to determine fair values and includes the following classifications: Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data.
Property and Equipment	Property and equipment are stated at lower of cost or realizable values. Depreciation is computed on the straight-line method over the estimated useful lives of the assets. Leasehold improvements are amortized over the shorter of the lease terms or the estimated useful lives. Maintenance and repairs are charged to expense as incurred and the costs of additions and betterments that increase the useful lives of the assets are capitalized.
Long-Lived Assets	We assess the impairment of long-lived assets whenever events or changes in circumstances indicate their carrying value may not be recoverable from the undiscounted estimated future cash flows expected to result from their use. We are required to make judgments and assumptions in identifying those events or changes in circumstances that may trigger impairment. Some of the factors we consider include: • Significant decrease in the market value of an asset. • Significant changes in the extent or manner for which the asset is being used or in its physical condition including manufacturing plant closures. • A significant change, delay or departure in our business strategy related to the asset. • Significant negative changes in the business climate, industry or economic conditions. • Current period operating losses or negative cash flow combined with a history of similar losses or a forecast indicates continuing losses associated with the use of an asset. If events or circumstances indicate the carrying amount of a long-lived asset or asset group may not be recoverable and the expected undiscounted future cash flows attributable to the asset group are less than the carrying value, an impairment loss equal to the excess of the carrying value of the assets within the asset group over their fair value is recorded. The appropriate asset group is determined based on the lowest level of largely independent cash inflows and outflows for the related assets. Depending on the nature of the primary assets in the asset group, fair value is estimated using one of several approaches including replacement cost, appraised values, market quotes or estimated expected future cash flows using a discount rate commensurate with the risk involved.
Goodwill and Intangible Assets	We account for goodwill on an impairment-only approach and amortize intangible assets with definite useful lives over the benefit period, which approximates straight-line expense over the respective useful lives. We assess qualitative factors to determine whether it is more likely than not an indefinite-lived intangible asset such as goodwill is impaired as the basis for determining whether a quantitative impairment test is required. We assess definite-lived intangible assets for impairment whenever events or changes in circumstances indicate the carrying value of an asset may not be fully recoverable. Whenever we determine there has been an impairment of goodwill or other intangible assets with indefinite lives, we will record an impairment charge against earnings. We operate as one reporting unit and an impairment charge would equal the excess of the carrying value of goodwill in our one reporting unit over its then fair value. The identification of intangible assets and determination of the fair value and useful lives are subjective in nature and often involve the use of significant estimates and assumptions. The judgments made in determining the estimated useful lives assigned to each class of assets can significantly affect net income.
Revenue Recognition, Sales Returns and Allowances	We primarily recognize revenue from customers, including distributors, when title and risk of loss have passed to the customer provided that: 1) evidence of an arrangement exists; 2) delivery has occurred; 3) the fee is fixed or determinable; and 4) collectability is reasonably assured. For substantially all sales, revenue is recognized, net of estimated returns and discounts, at the time the product is shipped. We enter into distribution agreements that permit rights to limited stock rotations, returns, price protection, and volume purchase and other discounts. We provide an estimated allowance for these rights and record a corresponding reduction in revenue. Our estimated allowance is based on several factors including past history and notification from customers of pending activity. Actual activity under such rights have been within management’s expectations. We also derive a portion of our revenue from fixed-price contracts. Revenue for these contracts is recorded under a percentage of completion method, which is based on the ratio of total costs incurred to date to estimated total costs at completion. Actual costs have been within management’s expectations. Gross profit expected to be realized on fixed-price contracts is based on periodic estimates of total revenues and costs for each contract. Losses on contracts are accrued when estimated total costs are expected to exceed total revenues. Occasionally, we will enter into contracts on a cost plus fee basis. We recognize revenue based on reimbursements for actual expenses plus the contractually agreed upon fee with the customer.
Research and Development	We expense the cost of research and development as incurred. Research and development expenses principally comprise payroll and related costs, supplies, and the cost of prototypes.
Restructuring Charges	We recognize a liability for restructuring costs when the liability is incurred. The restructuring accruals are based upon management estimates at the time they are recorded and can change depending upon changes in facts and circumstances subsequent to the date the original liability is recorded. The main components of our restructuring charges are workforce reductions and elimination of excess facilities. Workforce-related charges are accrued when it is determined a liability exists, which is generally when individuals have been notified of their expected termination dates and expected severance payments and when formal severance plans exist, when the severance payments are probable and reasonably estimable. The elimination of excess facilities results in charges for lease termination fees, future contractual commitments to pay lease charges net of estimated sublease income, facility remediation costs and moving costs to remove property and equipment from the facilities. We recognize charges for elimination of excess facilities when we have vacated the premises or ceased use of a functionally separate portion of the facility.
Stock-Based Compensation	Compensation expense for stock options and stock appreciation rights was calculated based on the on the service period of the grant and the grant date or assumption date fair value using the Black-Scholes pricing model. All stock appreciation rights we have granted or assumed are stock-settled. Stock options and stock appreciation rights are granted at exercise prices equal to the closing price of our common stock on the date of grant. Assumed stock options and stock appreciation rights are granted at exercise prices determined in accordance with the acquisition agreement. Expected life and forfeiture rates were estimated based primarily on historical data that were stratified between members of the Board of Directors, executive employees and all other recipients. Expected volatility was estimated based on historical volatility using equally weighted daily price observations over a period approximately equal to the expected life of each option. The risk free interest rate is based on the implied yield currently available on U.S. Treasury securities with an equivalent remaining term. No dividends are expected to be paid. Compensation expense for restricted shares was calculated based on the service period of the grant and the closing price of our common stock on the date of grant. Restricted shares are subject to forfeiture if a participant does not meet length of service requirements. Restricted stock awards granted to employees typically vest over a three year period and awards granted to non-employee directors vest in accordance with our director compensation policy. Compensation expense for performance stock units was calculated based upon expected achievement of the performance metrics specified in the grant and the closing price of our common stock on the date of grant, or when a grant contains a market condition, the grant date fair value using a Monte Carlo simulation. The Monte Carlo simulation incorporates estimates of the potential outcomes of the market condition on the grant date fair value of each award.
Accounting For Income Taxes	We account for income taxes under the asset and liability method, whereby 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. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. We evaluate the need to establish a valuation allowance for deferred tax assets based upon the amount of existing temporary differences, the period in which they are expected to be recovered and expected levels of taxable income. A valuation allowance to reduce deferred tax assets are established when it is more likely than not some or all of the deferred tax assets will not be realized. We recognize uncertain tax positions when they meet a more-likely-than-not threshold. We recognize potential accrued interest and penalties related to unrecognized tax benefits as income tax expense. We file U.S. federal, state, and foreign income tax returns in jurisdictions with varying statutes of limitations. We establish liabilities for possible assessments by tax authorities resulting from known tax exposures including, but not limited to, international tax issues and certain tax credits. While we believe our reported results are appropriate, any significant adjustments could have a material adverse effect on our results of operations, cash flows and financial position if not resolved within management expectations.
Segment Information	We use the management approach for segment disclosure, which designates the internal organization that is used by management for making operating decisions and assessing performance as the source of our reportable segments. We manage our business on the basis of one reportable segment, as a manufacturer of semiconductors in different geographic areas, including the United States, Europe and Asia.
Foreign Currency	All of our significant subsidiaries outside the United States use the United States dollar ("USD") as their functional currency. We have one subsidiary in China that uses the Chinese renminbi ("RMB") as its functional currency. For subsidiaries that use USD as the functional currency, assets and liabilities are remeasured to USD at the exchange rate in effect at the balance sheet date except for non-monetary assets and capital accounts which are measured at historical rates; revenues, expenses, gains and losses are remeasured at rates of exchange that approximate the rates in effect at the transaction date. For subsidiaries that use the local currency as the functional currency, all assets and liabilities are translated to USD using exchange rates in effect at the end of the period. Resulting translation gains or losses are recognized as a component of other comprehensive income. We also conduct a relatively small portion of our business in a number of foreign currencies, principally the European Union Euro, Canadian Dollar, British Pound, Israeli Shekel and Chinese RMB.
Earnings Per Share	Basic earnings per share have been computed based upon the weighted-average number of common shares outstanding during the respective periods. Diluted earnings per share have been computed, when the result is dilutive, using the treasury stock method for stock awards outstanding during the respective periods.
Concentration of Credit Risk and Foreign Sales	Concentrations of credit risk exist because we rely on a number of customers whose principal sales are to the U.S. Government. Approximately 30% of total net sales in 2016 were in the Aerospace & Defense end market and while we service defense markets outside of the United States, a portion of sales in this end market correlate to sales to U.S. government agencies, customers whose principal sales are to the U.S. government agencies or to subcontractors whose material sales are to the U.S. government agencies. We, as a subcontractor, sell our products to higher-tier subcontractors or to prime contractors based upon purchase orders that usually do not contain all of the conditions included in the prime contract with the U.S. Government. However, these sales are usually subject to termination and/or price renegotiations by virtue of their reference to a U.S. Government prime contract. Therefore, we believe all of our product sales that ultimately are sold to the U.S. Government may be subject to termination, at the convenience of the U.S. Government or to price renegotiations under the Renegotiation Act. In addition, the shutdown of non-essential U.S. Government services in October 2013 and any future government shutdowns may significantly increase the risk of contract terminations or renegotiations. At least one of our contracts has been terminated in the past due to the termination of the underlying government contract. There can be no assurance we will not have contract termination or price renegotiation in the future, and any such termination or renegotiation could have a material adverse impact upon our revenues and results of operations. In addition, net sales to international markets represent a significant portion of total net sales. Our net sales to international customers represented 62% , 51% and 47% of consolidated net sales for 2016 , 2015 and 2014 , respectively. These sales were principally to customers in Europe and Asia. We maintain reserves for potential credit losses and such losses have been within management’s expectations.
Recently Issued Accounting Standards	Recently Adopted Accounting Pronouncement In November 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-17, Balance Sheet Classification of Deferred Taxes, which requires all deferred tax assets and liabilities, as well as related valuation allowances, to be classified as noncurrent rather than as current and non-current based on the classification of the related assets and liabilities. The guidance is effective for annual and interim reporting periods beginning after December 15, 2016, and may be applied either prospectively or retrospectively. Early adoption is permitted. We elected to early adopt the provisions of this update at the beginning of our fourth quarter of fiscal 2016 and accordingly has classified deferred tax assets and liabilities, together with the corresponding valuation allowance as noncurrent in the consolidated balance sheet. We adopted the provisions of this update retrospectively and therefore reclassified and reduced $26.2 million of current deferred income tax assets, increased $8.1 million of noncurrent deferred income tax assets and reduced $18.1 million of noncurrent deferred income tax liabilities in our fiscal year 2015 comparative consolidated balance sheet. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. Several aspects of the accounting for share-based payment award transactions are simplified, including: (a) income tax consequences; (b) classification of awards as either equity or liabilities; (c) classification on the statement of cash flows; and (d) classification of related deferred tax balances as non-current. The amendments in this update are effective for annual periods beginning after December 16, 2016, and interim periods within those fiscal years. Early adoption is permitted. We elected to early adopt this ASU during our fiscal year 2016 and adoption did not impact our consolidated balance sheets, results of operations or cash flows. In August 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. The standard provides guidance for eight targeted changes with respect to how cash receipts and cash payments are classified in the statements of cash flows, with the objective of reducing diversity in practice. The standard is effective for financial statements issued for fiscal years beginning after December 15, 2017 (The Company's fiscal quarter of fiscal 2019), with early adoption permitted. We elected to early adopt this new guidance and accordingly have classified cash payments made during the second quarter of our fiscal year 2016 related to debt extinguishment amounting to approximately $61.3 million as cash flows used in financing activities that was previously reported in our quarterly consolidated financial statements as cash flows used in operating activities. The early adoption this ASU did not impact our prior period consolidated statements of cash flows. Recently Issued Accounting Standards not yet Adopted In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2014-09 which provides guidance on how an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the Entity expects to be entitled in exchange for those goods or services and on accounting for costs to obtain or fulfill a contract with a customer. The ASU also requires expanded disclosure regarding the nature, amount, timing and uncertainty of revenue that is recognized. In July 2015, the FASB decided to delay the effective date of this ASU by one year. This ASU, as amended, will be effective for the Company beginning in the first quarter of fiscal 2019 and can be adopted either full retrospective or modified retrospective with the cumulative effect recognized as of the date of adoption. Early adoption is permitted, but no earlier than fiscal 2018. We expect to adopt this ASU on a modified retrospective basis in the first quarter of fiscal 2019, and we are currently assessing the impact of this ASU on our consolidated financial statements. The FASB since issued additional updates of its new standard on revenue recognition issued in May 2014. In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606) - Principal versus Agent Considerations, which clarifies the implementation guidance for principal versus agent considerations in ASU 2014-09. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606) - Identifying Performance Obligations and Licensing, which amends the guidance in ASU 2014-09 related to identifying performance obligations and accounting for licenses of intellectual property. We are currently assessing the adoption and impact of these ASUs on our consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which modified lease accounting for both lessees and lessors to increase transparency and comparability by recognizing lease assets and lease liabilities by lessees for those leases classified as operating leases under previous accounting standards and disclosing key information about leasing arrangements. This ASU will be effective for the Company beginning in the first quarter of fiscal 2020 on a modified retrospective basis. Early adoption is permitted. We are currently evaluating the impact of adopting the new lease standard on our consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments -Credit Loses (Topic 326): Measurement of Credit Losses on Financial Instruments. The ASU requires measurement and recognition of expected credit losses for financial assets held based on historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. The ASU will be effective for the Company beginning in the first quarter of fiscal 2021 on a modified retrospective basis and early adoption in fiscal 2020 is permitted. We are currently assessing the timing of adoption and impact of these ASUs on our consolidated financial statements.

Description of business and s24

Description of business and summary of significant accounting policies (Tables)	12 Months Ended
	Oct. 02, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Fair Value, Assets Measured on Recurring Basis	The following financial assets and liabilities were measured at fair value on a recurring basis using the type of inputs indicated below and are as follows (amounts in millions): Fair Value Measurements Using: Total Level 1 Inputs Level 2 Inputs Level 3 Inputs October 2, 2016 Investment in marketable securities $ 1.3 $ 1.3 $ — $ — September 27, 2015 Investment in marketable securities $ 1.7 $ 1.7 $ — $ —
Earnings Per Share	Earnings per share for 2016 , 2015 and 2014 were calculated as follows (amounts in millions, except per share data): Fiscal Years 2016 2015 2014 Basic Net (loss) income $ (32.6 ) $ 84.6 $ 23.1 Weighted-average common shares outstanding 107.0 94.2 92.9 Basic (loss) earnings per share $ (0.31 ) $ 0.90 $ 0.25 Diluted Net (loss) income $ (32.6 ) $ 84.6 $ 23.1 Weighted-average common shares outstanding for basic 107.0 94.2 92.9 Dilutive effect of stock awards — 1.7 1.6 Weighted-average common shares outstanding on a diluted basis 107.0 95.9 94.5 Diluted (loss) earnings per share $ (0.31 ) $ 0.88 $ 0.24

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Oct. 02, 2016
Business Combinations [Abstract]
Schedule of Business Acquisitions by Acquisition, Contingent Consideration	A summary of the consideration for PMC is as follows (amounts in millions): Cash consideration $ 1,994.4 Share consideration 474.5 Assumption of equity awards 15.7 Accrued cash consideration 0.3 Total consideration $ 2,484.9
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	We recorded PMC's tangible and intangible assets and liabilities based on their estimated fair values as of the Acquisition Date and allocated the remaining purchase consideration to goodwill. The allocation is as follows (amounts in millions): Cash and cash equivalents $ 313.0 Accounts receivable 53.3 Inventories 98.2 Other current assets 15.8 Property and equipment 38.0 Other assets 19.7 Identifiable intangible assets 747.6 Goodwill 1,472.3 Deferred income taxes, net (87.3 ) Current liabilities (121.6 ) Other non-current liabilities (64.1 ) Total consideration $ 2,484.9
Schedule of Acquired Finite-Lived Intangible Assets by Major Class	The valuation of identifiable intangible assets and their estimated useful lives are as follows (amounts in millions): Asset Amount Weighted Average Useful Life (Years) Completed technology $ 447.0 6 In-process research and development 241.0 Customer relationships 52.0 9 Other 7.6 1 $ 747.6
Business Acquisition, Pro Forma Information	Supplemental pro forma data is as follows (amounts in millions): 2016 2015 Net sales $ 1,804.5 $ 1,773.9 Net income (loss) $ 82.3 $ (168.0 ) Earnings (loss) per share: Basic $ 0.74 $ (1.52 ) Diluted $ 0.72 $ (1.52 )

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Oct. 02, 2016
Inventory Disclosure [Abstract]
Inventories	Inventories consisted of the following components (amounts in millions): October 2, September 27, Raw materials $ 32.8 $ 56.5 Work in progress 112.8 111.7 Finished goods 67.5 59.0 $ 213.1 $ 227.2

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Oct. 02, 2016
Property, Plant and Equipment [Abstract]
Components of Property Plant and Equipment	Property and equipment consisted of the following components (dollar amounts in millions): Asset Life October 2, September 27, Buildings 20-40 years $ 37.2 $ 43.0 Machinery and equipment 3-10 years 439.3 429.1 Furniture and fixtures 5-10 years 8.9 9.8 Leasehold improvements Shorter of asset life or life of lease 62.6 54.1 548.0 536.0 Accumulated depreciation (382.2 ) (393.8 ) Land 1.5 1.9 Construction in progress 7.6 8.6 $ 174.9 $ 152.7

Goodwill and Intangible Asset28

Goodwill and Intangible Assets, Net (Tables)	12 Months Ended
	Oct. 02, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and intangible assets, net consisted of the following components (dollar amounts in millions): October 2, 2016 September 27, 2015 Life (in years) Gross Accumulated Gross Accumulated Amortizable intangible assets Completed technology $ 907.7 $ (335.1 ) $ 489.7 $ (251.7 ) 2 to 15 Customer relationships 338.0 (219.2 ) 316.2 (197.1 ) 4 to 15 Backlog, trade name and other 24.9 (22.7 ) 18.8 (18.1 ) 1 to 5 $ 1,270.6 $ (577.0 ) $ 824.7 $ (466.9 ) Non-amortizable intangible assets Goodwill $ 2,479.4 $ 1,139.3 In-process research and development $ 241.0 $ —
Reconciliation of Goodwill	A reconciliation of our goodwill for the years ended October 2, 2016 and September 27, 2015 is as follows (amounts in millions): October 2, 2016 September 27, 2015 Beginning balance $ 1,139.3 $ 885.6 Additions from acquisitions 1,472.3 253.7 Reductions from divestitures (125.0 ) — Carrying value of goodwill classified as assets held for sale (7.2 ) — Ending balance $ 2,479.4 $ 1,139.3
Finite-lived Intangible Assets Amortization Expense	Amortization of intangible assets included in operating expenses for each of the three fiscal years in the period ended October 2, 2016 is as follows (amounts in millions): 2016 2015 2014 Completed technology $ 108.7 $ 50.4 $ 43.9 Customer relationships 46.5 44.6 45.0 Backlog, trade name and other 6.0 1.5 3.9 $ 161.2 $ 96.5 $ 92.8
Estimated Amortization Expense	Estimated amortization expense in each of the five succeeding years and thereafter is as follows (amounts in millions): 2017 2018 2019 2020 2021 Thereafter $ 174.3 $ 130.7 $ 111.1 $ 105.8 $ 105.8 $ 65.7

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Oct. 02, 2016
Accounts Payable and Accrued Liabilities, Current [Abstract]
Components of Accrued Liabilities	Accrued liabilities consisted of the following components (amounts in millions): October 2, September 27, Payroll, bonus and employee benefits $ 53.8 $ 33.3 Interest 31.2 — Licenses 26.0 6.0 Deferred revenue 15.1 9.7 Outside services 12.8 9.2 Warranties 7.5 6.4 Restructuring and severance 4.6 2.5 Commissions 4.3 3.8 Property and sales taxes 2.4 1.3 Leases and rent 2.5 2.6 Customer deposits 1.1 2.2 Other 4.8 9.8 $ 166.1 $ 86.8

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Oct. 02, 2016
Income Tax Disclosure [Abstract]
Pretax Income (Loss)	Pretax income (loss) was generated from the following sources for each of the three fiscal years in the period ended October 2, 2016 (amounts in millions): 2016 2015 2014 Domestic $ (112.5 ) $ (14.9 ) $ (62.7 ) Foreign 87.1 111.8 86.6 Total $ (25.4 ) $ 96.9 $ 23.9
Provision (Benefit) of Income Taxes	The provision for income taxes consisted of the following components for each of the three fiscal years in the period ended October 2, 2016 (amounts in millions): 2016 2015 2014 Current: State 0.2 0.2 0.3 Foreign 4.3 4.2 3.9 Deferred: Federal 4.1 4.6 (6.5 ) State 0.2 — (0.2 ) Foreign (1.6 ) 3.3 3.3 $ 7.2 $ 12.3 $ 0.8
Reconciliation of income Tax Computed at the Federal Statutary Rate	The following is a reconciliation of income tax computed at the federal statutory rate to our actual tax expense for each of the three fiscal years in the period ended October 2, 2016 (amounts in millions): 2016 2015 2014 Tax computed at federal statutory rate $ (8.9 ) $ 33.9 $ 8.4 State taxes, net of federal impact 0.5 (2.1 ) (1.1 ) Foreign income taxed at different rates (7.0 ) (33.1 ) (24.7 ) Tax credits and incentives (10.7 ) (5.1 ) (2.8 ) Stock award compensation (4.6 ) 1.3 1.2 Unrecognized tax benefits 30.6 3.7 1.4 Sale/transfer of assets (45.6 ) — — U.S. tax on foreign income 2.0 1.3 4.1 Non-deductible permanent items 6.2 0.9 0.9 Pre-acquisition loss carry forwards — — (11.4 ) Expiration of tax attributes 5.0 — 2.9 Investment in foreign subsidiaries 2.7 (0.5 ) 3.6 Withholding taxes 1.1 (0.3 ) 0.3 Other differences, net 0.6 (1.0 ) 0.4 Valuation allowance 35.3 13.3 17.6 $ 7.2 $ 12.3 $ 0.8
Components of Deferred Tax Assets (Liabilities)	The tax effected deferred tax assets (liabilities) are comprised of the following components (amounts in millions): October 2, September 27, 2015 Accounts receivable, net $ 2.1 $ 1.9 Inventories 18.8 17.5 Accrued employee benefit expenses 10.0 8.4 Net operating losses 216.1 164.6 Tax credits and incentives 238.0 153.5 Accrued other expenses 10.3 9.7 Deferred equity compensation 20.0 18.9 Property and equipment, net 4.4 13.8 Debt issuance costs 20.9 0.3 Other assets 12.3 11.1 Total deferred tax assets 552.9 399.7 Intangible assets (176.8 ) (137.1 ) Investment in foreign subsidiaries (2.5 ) — Total deferred tax liabilities (179.3 ) (137.1 ) Less valuation allowance (456.4 ) (250.6 ) $ (82.8 ) $ 12.0
Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (amounts in millions): October 2, September 27, September 28, 2014 Beginning gross unrecognized tax benefits $ 121.8 $ 97.7 $ 69.6 Additions based on tax positions related to the current year 33.1 3.5 2.4 Additions based on current year acquisitions 132.6 16.2 28.9 Additions based on tax positions of prior years 36.3 4.8 0.4 Reductions for lapses and settlements (4.8 ) (0.4 ) (3.6 ) Ending gross unrecognized tax benefit $ 319.0 $ 121.8 $ 97.7

Debt (Tables)

Debt (Tables)	12 Months Ended
	Oct. 02, 2016
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments and Interest Rates	T

Other Long-Term Liabilities (Ta

Other Long-Term Liabilities (Tables)	12 Months Ended
	Oct. 02, 2016
Other Liabilities Disclosure [Abstract]
Other Long-Term Liabilities	Other long-term liabilities consisted of (amounts in millions): October 2, September 27, Unrecognized tax benefits $ 70.6 $ 19.8 Deferred rent 17.2 11.2 Pension and retirement 14.2 8.9 Restructuring 4.2 3.4 Other 9.6 3.0 Total $ 115.8 $ 46.3

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Oct. 02, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity	Activity and price information related to restricted stock awards are as follows (quantity in millions): Quantity Weighted-Average Grant Price Outstanding at September 29, 2013 3.1 Granted 1.6 $ 24.67 Vested (1.4 ) Forfeited (0.2 ) Outstanding at September 28, 2014 3.1 Assumed from acquisition 0.3 $ 33.01 Granted 1.3 $ 29.37 Vested (1.5 ) Forfeited (0.2 ) Outstanding at September 27, 2015 3.0 Assumed from acquisition 1.9 $ 29.77 Granted 1.3 $ 32.15 Vested (2.1 ) Forfeited (0.5 ) Outstanding at October 2, 2016 3.6
Schedule of Performance Incentive Plan Vesting Levels	Under the award agreement, the vesting of the RSUs is contingent on the Company’s stock price achieving specified levels during the five -year period after the date of grant of the award (the “performance period”) as follows: Stock Price Level Percentage of Total Award That Vests $50.00 25% $60.00 50% $70.00 25%
Schedule of Nonvested Performance-based Units Activity	Activity and price information related to performance units are as follows (quantity reported at target and in millions): Quantity Outstanding at September 29, 2013 0.6 Granted 0.4 Vested (0.3 ) Outstanding at September 28, 2014 0.7 Granted 0.3 Vested (0.3 ) Outstanding at September 27, 2015 0.7 Granted 1.5 Vested (0.5 ) Outstanding at October 2, 2016 1.7
Activity and Price Information Related to Stock Options and Stock Appreciation Rights	Activity and price information related to stock options and stock appreciation rights are as follows (quantity and intrinsic value in millions): Quantity Weighted-Average Exercise Price Intrinsic Value Weighted Average Remaining Life (Years) Outstanding at September 29, 2013 4.7 $ 22.49 $ 14.7 1.7 Assumed from acquisition 0.6 $ 20.08 Exercised (1.2 ) $ 16.39 $ 17.0 Forfeited (1.4 ) $ 26.55 Outstanding at September 28, 2014 2.7 $ 22.70 $ 7.4 2.0 Assumed from acquisition 0.2 $ 24.18 Exercised (2.1 ) $ 23.83 $ 15.8 Forfeited (0.1 ) $ 23.90 Outstanding at September 27, 2015 0.7 $ 19.60 $ 9.1 4.0 Exercised (0.2 ) $ 21.16 Forfeited — $ 21.44 Outstanding at October 2, 2016 0.5 $ 18.75 $ 10.7 3.5 Exercisable at October 2, 2016 0.4 $ 18.24 $ 9.8 3.3 Exercisable and expected to vest after October 2, 2016 0.5 $ 18.75 $ 10.7 3.5
Schedule Of Additional Information About Stock Options and Stock Appreciation Rights Outstanding	Quantity and weighted-average exercise prices related to stock options and stock appreciation rights outstanding as of October 2, 2016 and stratified by exercise price are as follows (quantity in millions): Exercisable Outstanding Exercise Price Quantity Weighted-Average Exercise Price Quantity Weighted-Average Exercise Price Less than or equal to $20.00 0.3 $ 14.08 0.3 $ 14.17 Greater than $20.00 0.1 $ 25.87 0.2 $ 25.60 0.4 $ 18.24 0.5 $ 18.75

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Oct. 02, 2016
Commitments and Contingencies Disclosure [Abstract]
Aggregate Undiscounted Future Minimum Rental Payments	The aggregate undiscounted future minimum rental payments under these leases are as follows (amounts in millions): 2017 2018 2019 2020 2021 Thereafter $ 26.4 $ 24.0 $ 20.7 $ 17.8 $ 11.5 $ 16.7

Restructuring and Severance C35

Restructuring and Severance Charges (Tables)	12 Months Ended
	Oct. 02, 2016
Restructuring and Related Activities [Abstract]
Reflects the restructuring activities and the accrued liabilities	The following table reflects the related restructuring activities and the accrued liabilities at the dates below (amounts in millions): Employee Severance Contract Termination Costs Other Associated Costs Total Balance at September 27, 2015 $ 2.9 $ 3.2 $ 0.1 $ 6.2 Assumed from acquisition 2.9 — 0.1 3.0 Provisions 55.4 5.1 4.2 64.7 Reversal of prior provision (3.4 ) (0.3 ) (0.2 ) (3.9 ) Cash expenditures (32.4 ) (2.9 ) (0.9 ) (36.2 ) Other non-cash settlement (22.9 ) (0.5 ) (2.9 ) (26.3 ) Balance at October 2, 2016 $ 2.5 $ 4.6 $ 0.4 $ 7.5

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Oct. 02, 2016
Segment Reporting [Abstract]
Net Sales, End Market and Long Lived Assets by Geographic Area	Property and equipment, net by geographic area are as follows (amounts in millions): 2016 2015 2014 United States $ 119.2 $ 117.6 $ 117.9 Europe 16.4 13.9 12.2 Asia 22.6 18.9 16.8 Other 16.7 2.3 1.8 Total $ 174.9 $ 152.7 $ 148.7 Net sales based on a customer's ship-to location and by estimated end market are as follows (amounts in millions): 2016 2015 2014 United States $ 628.2 $ 610.0 $ 604.4 Europe 222.8 189.8 163.7 Asia 749.2 399.7 338.4 Other 54.8 46.1 31.8 Total $ 1,655.0 $ 1,245.6 $ 1,138.3 Aerospace & Defense $ 495.4 $ 527.2 $ 472.3 Communications 618.0 439.8 401.0 Data Center 276.9 11.9 6.6 Industrial 264.7 266.7 258.4 Total $ 1,655.0 $ 1,245.6 $ 1,138.3

Unaudited Selected Quarterly 37

Unaudited Selected Quarterly Financial Data (Tables)	12 Months Ended
	Oct. 02, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	Selected quarterly financial data are as follows (amounts in millions, except earnings (loss) per share): Quarters ended in fiscal year 2016 October 2, July 3, April 3, January 3, Net sales $ 450.1 $ 431.4 $ 444.3 $ 329.2 Cost of sales (excluding amortization of intangible assets) $ 168.3 $ 164.5 $ 243.7 $ 141.4 Gross profit $ 281.8 $ 266.9 $ 200.6 $ 187.8 Net income (loss) $ 40.5 $ 115.2 $ (212.0 ) $ 23.7 Basic earnings (loss) per share $ 0.36 $ 1.03 $ (1.93 ) $ 0.25 Diluted earnings (loss) per share $ 0.35 $ 1.00 $ (1.93 ) $ 0.25 Quarters ended in fiscal year 2015 September 27, June 28, March 29, December 28, Net sales $ 328.8 $ 317.1 $ 296.2 $ 303.5 Cost of sales (excluding amortization of intangible assets) $ 154.0 $ 145.0 $ 126.9 $ 135.4 Gross profit $ 174.8 $ 172.1 $ 169.3 $ 168.1 Net income $ 25.3 $ 14.7 $ 24.9 $ 19.7 Basic earnings per share $ 0.27 $ 0.16 $ 0.26 $ 0.21 Diluted earnings per share $ 0.26 $ 0.15 $ 0.26 $ 0.21

Description of business and s38

Description of business and summary of significant accounting policies - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Jan. 03, 2016	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Basis of Presentation [Line Items]
Document Fiscal Year Focus									2,016
Stock awards excluded from computation of diluted EPS										0.2	2.8
Net income	$ 40.5	$ 115.2	$ (212)	$ 23.7	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ (32.6)	$ 84.6	$ 23.1
Debt Issuance Cost									$ 44	11.7
Deferred Income Taxes and Other Assets, Noncurrent					8.1					8.1
Deferred Income Taxes and Other Tax Liabilities, Noncurrent					$ 18.1					$ 18.1
International
Basis of Presentation [Line Items]
Percentage of net sales from international market									62.00%	51.00%	47.00%
Defense And Security
Basis of Presentation [Line Items]
Concentration of credit risk in major customer									30.00%
Internal Revenue Service (IRS) | Minimum
Basis of Presentation [Line Items]
Open tax years by major tax jurisdiction									2,007
Internal Revenue Service (IRS) | Maximum
Basis of Presentation [Line Items]
Open tax years by major tax jurisdiction									2,015
Foreign Country | Minimum
Basis of Presentation [Line Items]
Open tax years by major tax jurisdiction									2,007
Foreign Country | Maximum
Basis of Presentation [Line Items]
Open tax years by major tax jurisdiction									2,015
Accounting Standards Update 2016-15 | Adjustments for New Accounting Principle, Early Adoption
Basis of Presentation [Line Items]
Debt extinguishment financing activities			$ 61.3
Noncurrent Assets | Accounting Standards Update 2015-17
Basis of Presentation [Line Items]
Deferred tax assets	26.2								$ 26.2
Current Assets | Accounting Standards Update 2015-17
Basis of Presentation [Line Items]
Deferred tax assets	$ (26.2)								$ (26.2)

Description of business and s39

Description of business and summary of significant accounting policies - Fair Value Measurements Using (Detail) - Measured on a recurring basis - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	$ 1.3	$ 1.7
Fair Value, Inputs, Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	1.3	1.7
Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	0	0
Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	$ 0	$ 0

Description of business and s40

Description of business and summary of significant accounting policies - Earning Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Jan. 03, 2016	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Document Fiscal Year Focus									2,016
Stock awards excluded from computation of diluted EPS										0.2	2.8
BASIC
Net income (loss)	$ 40.5	$ 115.2	$ (212)	$ 23.7	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ (32.6)	$ 84.6	$ 23.1
Weighted-average common shares outstanding									107	94.2	92.9
Basic earnings (loss) per share	$ 0.36	$ 1.03	$ (1.93)	$ 0.25	$ 0.27	$ 0.16	$ 0.26	$ 0.21	$ (0.31)	$ 0.90	$ 0.25
DILUTED
Net income (loss)	$ 40.5	$ 115.2	$ (212)	$ 23.7	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ (32.6)	$ 84.6	$ 23.1
Weighted-average common shares outstanding									107	94.2	92.9
Dilutive effect of stock awards									0	1.7	1.6
Weighted-average common shares outstanding on a diluted basis									107	95.9	94.5
Diluted earnings (loss) per share	$ 0.35	$ 1	$ (1.93)	$ 0.25	$ 0.26	$ 0.15	$ 0.26	$ 0.21	$ (0.31)	$ 0.88	$ 0.24

Acquisitions (Detail)

Acquisitions (Detail) $ / shares in Units, shares in Millions

May 02, 2016USD ($)

Apr. 28, 2016USD ($)

Jan. 15, 2016USD ($)projectshares

Oct. 02, 2016USD ($)

Jul. 03, 2016USD ($)

Apr. 03, 2016USD ($)

Jan. 03, 2016USD ($)

Sep. 27, 2015USD ($)

Jun. 28, 2015USD ($)

Mar. 29, 2015USD ($)

Dec. 28, 2014USD ($)

Oct. 02, 2016USD ($)

Jun. 29, 2014USD ($)$ / shares

Oct. 02, 2016USD ($)$ / shares

Sep. 27, 2015USD ($)

Sep. 28, 2014USD ($)

Business Acquisition [Line Items]

Goodwill

$ 2,479,400,000

$ 1,139,300,000

$ 2,479,400,000

$ 2,479,400,000

$ 1,139,300,000

$ 885,600,000

Net sales

450,100,000

$ 431,400,000

$ 444,300,000

$ 329,200,000

328,800,000

$ 317,100,000

$ 296,200,000

$ 303,500,000

1,655,000,000

1,245,600,000

1,138,300,000

Business Acquisition, Pro Forma Information [Abstract]

Proceeds from the divestiture or sale of assets

321,000,000

0

$ 0

Gain on divestiture

$ 125,500,000

Disposal Group, Including Discontinued Operation, Assets, Current

13,900,000

$ 0

13,900,000

13,900,000

$ 0

Disposal Group, Including Discontinued Operation, Consideration

31,400,000

31,400,000

31,400,000

Disposal Group, Including Discontinued Operation, Goodwill

$ 7,200,000

7,200,000

7,200,000

PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Cost of Goods Sold

66,200,000

Payments to Acquire Businesses, Gross

$ 1,994,383,000

Cash consideration

2,484,900,000

Cash and cash equivalents

313,000,000

Accounts receivable

53,300,000

Inventories

98,200,000

Other current assets

15,800,000

Property and equipment

38,000,000

Other assets

19,700,000

Identifiable intangible assets

747,600,000

Goodwill

1,472,300,000

Current liabilities

(121,600,000)

Long term debt

(87,300,000)

Other non-current liabilities

(64,100,000)

Gross contractual amount of acquired receivables

53,300,000

Asset Amount

747,600,000

Initial purchase price accounting adjustment intangible assets

2,000,000

Initial purchase price accounting adjustment intangible assets current liabilities

17,600,000

Initial purchase price accounting adjustment intangible assets, noncurrent liabilities

3,600,000

Initial purchase price accounting adjustment, deferred income taxes

48,000,000

Initial purchase price accounting adjustment intangible assets, consideration transferred

9,500,000

Initial purchase price accounting adjustment goodwill

$ 41,500,000

Business Acquisition, Pro Forma Information [Abstract]

Net sales

1,804,500,000

Net income (loss)

$ 82,300,000

Basic (usd per share) | $ / shares

$ 0.74

Diluted (usd per share) | $ / shares

$ 0.72

Equity Issued in Business Combination, Fair Value Disclosure

15,700,000

Business Combination, Accrued Cash Consideration

300,000

Business Combination, Restructuring

$ 48,600,000

Business Combination, Acquisition Related Costs

$ 41,100,000

Vitesse

Business Acquisition, Pro Forma Information [Abstract]

Net sales

$ 1,773,900,000

Net income (loss)

$ (168,000,000)

Basic (usd per share) | $ / shares

$ (1.52)

Diluted (usd per share) | $ / shares

$ (1.52)

Completed technology | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Identifiable intangible assets

447,000,000

Asset Amount

$ 447,000,000

Useful life of intangible asset

6 years

Customer relationships | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Identifiable intangible assets

$ 52,000,000

Asset Amount

$ 52,000,000

Useful life of intangible asset

9 years

Other | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Identifiable intangible assets

$ 7,600,000

Asset Amount

$ 7,600,000

Useful life of intangible asset

1 year

Common Stock | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares

16

Business Acquisition, Pro Forma Information [Abstract]

Business Acquisition, Equity Interest Issued or Issuable, Value Assigned

$ 474,500,000

In Process Research and Development [Member] | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Fair Value Measurements, Valuation Techniques, Number Of Projects | project

4

Identifiable intangible assets

$ 241,000,000

Asset Amount

$ 241,000,000

Maximum | PMC-SIERRA INC. [Member]

Business Acquisition, Pro Forma Information [Abstract]

Business Acquisition, Net Sales Related to Products From Acquisition

25.00%

Maximum | Completed technology

Business Acquisition [Line Items]

Useful life of intangible asset

15 years

Maximum | Completed technology | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Useful life of intangible asset

8 years

Maximum | Customer relationships

Business Acquisition [Line Items]

Useful life of intangible asset

15 years

Maximum | In Process Research and Development [Member] | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Research And Development In Process, Expected Completion

2 years

Minimum | PMC-SIERRA INC. [Member]

Business Acquisition, Pro Forma Information [Abstract]

Business Acquisition, Net Sales Related to Products From Acquisition

20.00%

Minimum | Completed technology

Business Acquisition [Line Items]

Useful life of intangible asset

2 years

Minimum | Completed technology | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Useful life of intangible asset

5 years

Minimum | Customer relationships

Business Acquisition [Line Items]

Useful life of intangible asset

4 years

Minimum | In Process Research and Development [Member] | PMC-SIERRA INC. [Member]

Business Acquisition [Line Items]

Research And Development In Process, Expected Completion

6 months

Microsemi LLC - RF Integrated Solutions (RF LLC) [Member]

Business Acquisition, Pro Forma Information [Abstract]

Proceeds from the divestiture or sale of assets

$ 300,000,000

Remote Radio Head [Member]

Business Acquisition [Line Items]

Proceeds from Divestiture of Businesses, Net of Cash Divested

$ 21,000,000

Inventories (Detail)

Inventories (Detail) - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 32.8	$ 56.5
Work in progress	112.8	111.7
Finished goods	67.5	59
Total	$ 213.1	$ 227.2

Property and Equipment (Detail)

Property and Equipment (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 548	$ 536
Accumulated depreciation	(382.2)	(393.8)
Land	1.5	1.9
Construction in progress	7.6	8.6
Property and equipment, net	$ 174.9	152.7	$ 148.7
Property plant and equipment useful life	Shorter of asset life or life of lease
Depreciation expense	$ 46.1	36.2	$ 32.9
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	37.2	43
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	439.3	429.1
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	8.9	9.8
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 62.6	$ 54.1
Property plant and equipment useful life	Shorter of asset life or life of lease
Minimum | Buildings
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life	20 years
Minimum | Machinery and equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life	3 years
Minimum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life	5 years
Maximum | Buildings
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life	40 years
Maximum | Machinery and equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life	10 years
Maximum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life	10 years

Goodwill and Intangible Asset44

Goodwill and Intangible Assets, Net - Goodwill and Intangible Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	$ 1,270.6	$ 824.7
Accumulated Amortization	(577)	(466.9)
Goodwill	2,479.4	1,139.3	$ 885.6
Completed technology
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	907.7	489.7
Accumulated Amortization	(335.1)	(251.7)
Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	338	316.2
Accumulated Amortization	(219.2)	(197.1)
Backlog, trade name and other
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	24.9	18.8
Accumulated Amortization	$ (22.7)	(18.1)
Minimum | Completed technology
Goodwill and Intangible Assets Disclosure [Line Items]
Life (years)	2 years
Minimum | Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Life (years)	4 years
Minimum | Backlog, trade name and other
Goodwill and Intangible Assets Disclosure [Line Items]
Life (years)	1 year
Maximum | Completed technology
Goodwill and Intangible Assets Disclosure [Line Items]
Life (years)	15 years
Maximum | Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Life (years)	15 years
Maximum | Backlog, trade name and other
Goodwill and Intangible Assets Disclosure [Line Items]
Life (years)	5 years
In Process Research and Development [Member]
Goodwill and Intangible Assets Disclosure [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 241	$ 0

Goodwill and Intangible Asset45

Goodwill and Intangible Assets, Net - Reconciliation of Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Beginning balance	$ 1,139.3	$ 885.6
Additions from acquisitions	1,472.3	253.7
Reductions from divestitures	(125)	0
Carrying value of goodwill classified as assets held for sale	(7.2)
Ending balance	$ 2,479.4	$ 1,139.3

Goodwill and Intangible Asset46

Goodwill and Intangible Assets, Net - Amortization of Intangible Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	$ 161.2	$ 96.5	$ 92.8
Completed technology
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	108.7	50.4	43.9
Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	46.5	44.6	45
Backlog, trade name and other
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	$ 6	$ 1.5	$ 3.9

Goodwill and Intangible Asset47

Goodwill and Intangible Assets, Net - Estimated Amortization Expense (Detail) $ in Millions	Oct. 02, 2016USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,016	$ 174.3
2,017	130.7
2,018	111.1
2,019	105.8
2,020	105.8
Thereafter	$ 65.7

Accrued Liabilities (Detail)

Accrued Liabilities (Detail) - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Accounts Payable and Accrued Liabilities, Current [Abstract]
Payroll, bonus, and employee benefits	$ 53.8	$ 33.3
Deferred revenue	15.1	9.7
Outside services	12.8	9.2
Warranties	7.5	6.4
Commissions	4.3	3.8
Licenses	26	6
Accrued Rent, Current	2.5	2.6
Restructuring and severance	4.6	2.5
Customer Deposits, Current	1.1	2.2
Property and sales tax	2.4	1.3
Interest	31.2	0
Other	4.8	9.8
Total	$ 166.1	$ 86.8

Income Taxes - Pretax Income (L

Income Taxes - Pretax Income (Loss) (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Disclosure - Pretax Income (Loss) [Abstract]
Domestic	$ (112.5)	$ (14.9)	$ (62.7)
Foreign	87.1	111.8	86.6
Income (loss) before income taxes	$ (25.4)	$ 96.9	$ 23.9

Income Taxes - Provision for In

Income Taxes - Provision for Income Taxes (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Income Tax Disclosure [Abstract]
State	$ 0.2	$ 0.2	$ 0.3
Foreign	4.3	4.2	3.9
Federal	4.1	4.6	(6.5)
State	0.2	0	(0.2)
Foreign	(1.6)	3.3	3.3
Income Tax Expense (Benefit)	$ 7.2	$ 12.3	$ 0.8

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Income Taxes [Line Items]
Income Tax Expense (Benefit)	$ 7.2	$ 12.3	$ 0.8
Income (loss) before income taxes	(25.4)	96.9	23.9
Increase in valuation allowance	(205.9)	31.6
Excess tax benefit from employee stock compensation	213.5
Tax credits that carryforward indefinitely	9
Deferred Tax Assets, Capital Loss Carryforwards	0.6
Undistributed earnings of foreign operations	793.8	471.2
Unrecognized tax benefit, interest and penalties	3.7	0.7	$ 0.7
Unrecognized tax benefit, cumulative interest and penalties	42	$ 7.4
Unrecognized tax benefit that would impact effective tax rate	114.9
within the next twelve months
Income Taxes [Line Items]
Anticipated decrease in unrecognized tax benefits	17.2
Internal Revenue Service (IRS)
Income Taxes [Line Items]
Net operating losses carryforward, subject to expiration	671.7
Research and experimentation credits	125.5
Federal foreign tax credits	38.4
State and Local Jurisdiction
Income Taxes [Line Items]
Net operating losses carryforward, subject to expiration	713.6
Research and experimentation credits	111.2
Foreign Country
Income Taxes [Line Items]
Research and experimentation credits	139.6
Tax credit related to incentive deductions	$ 26.2
Minimum | Internal Revenue Service (IRS)
Income Taxes [Line Items]
Open tax years by major tax jurisdiction	2,007
Minimum | Foreign Country
Income Taxes [Line Items]
Open tax years by major tax jurisdiction	2,007
Maximum | Internal Revenue Service (IRS)
Income Taxes [Line Items]
Open tax years by major tax jurisdiction	2,015
Maximum | Foreign Country
Income Taxes [Line Items]
Open tax years by major tax jurisdiction	2,015

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Tax Computed at the Federal Statutory Rate to Actual Tax Expenses (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Income Tax Disclosure [Abstract]
Tax computed at federal statutory rate	$ (8.9)	$ 33.9	$ 8.4
State taxes, net of federal impact	0.5	(2.1)	(1.1)
Foreign income taxed at different rates	(7)	(33.1)	(24.7)
Tax credits	(10.7)	(5.1)	(2.8)
Stock award compensation	(4.6)	1.3	1.2
Unrecognized tax benefits	30.6	3.7	1.4
Business Combination, Consideration Transferred, Other	(45.6)	0	0
U.S. tax on foreign income	2	1.3	4.1
Non-deductible permanent items	6.2	0.9	0.9
Pre-acquisition loss carryforwards	0	0	(11.4)
Effective Income Tax Reconciliation, Prior Year Adjustments On Deferred Taxes	5	0	2.9
Effective Income Tax Reconciliation, Deduction, Foreign Declared Dividends, Amount	2.7	(0.5)	3.6
Withholding taxes	1.1	(0.3)	0.3
Other differences, net	0.6	(1)	0.4
Valuation allowance	35.3	13.3	17.6
Income Tax Expense (Benefit)	$ 7.2	$ 12.3	$ 0.8

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Income Tax Disclosure [Abstract]
Accounts receivable, net	$ 2.1	$ 1.9
Inventories	18.8	17.5
Accrued employee benefit expenses	10	8.4
Net operating losses	216.1	164.6
Tax credits	238	153.5
Accrued other expenses	10.3	9.7
Deferred equity compensation	20	18.9
Property and equipment, net	(4.4)	(13.8)
Debt issuance costs	20.9	0.3
Other assets	12.3	11.1
Total deferred tax assets	552.9	399.7
Intangible assets	(176.8)	(137.1)
Foreign declared dividend	(2.5)	0
Total deferred tax liabilities	(179.3)	(137.1)
Less valuation allowance	(456.4)	(250.6)
Deferred tax assets (liabilities), net	$ 82.8
Deferred tax assets (liabilities), net		$ 12

Income Taxes - Reconciliation54

Income Taxes - Reconciliation of the Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning gross unrecognized tax benefits	$ 121.8	$ 97.7	$ 69.6
Additions based on tax positions related to the current year	33.1	3.5	2.4
Additions based on current year acquisitions	132.6	16.2	28.9
Additions based on tax positions of prior years	36.3	4.8	0.4
Reductions for lapses and settlements	(4.8)	(0.4)	(3.6)
Ending gross unrecognized tax benefit	$ 319	$ 121.8	$ 97.7

Debt (Detail)

Debt (Detail) - USD ($) $ in Millions	Jan. 15, 2016	Apr. 28, 2015	Jul. 03, 2016	Apr. 03, 2016	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,500
Line of credit, obligation limit as percentage of assets or revenues					5.00%
Line of credit, subsidiary limit to be become a guarantor of consolidated assets					15.00%
Line of credit, subsidiary limit to be become a guarantor of consolidated revenues					15.00%
Debt Financing Fees Including Gain (Loss) On Extinguishment of Debt				$ 112.2	$ 19.1
Debt Financing Fees, Related to Gain (Loss) On Extinguishment Of Debt, Included In Operating Activities					16.1
Payments of Debt Issuance Costs			$ 3		53.8	$ 8.7	$ 1.5
Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term Debt		$ 275
Line of Credit Facility, Maximum Borrowing Capacity	325
Term Loan
Line of Credit Facility [Line Items]
Debt Instrument, Periodic Payment, Principal					2,223.2
Debt Instrument, Face Amount	1,773.2
Debt Instrument, Fair Value Disclosure					1,772.1
Term Loan | Term Loan A Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	450
Debt Instrument, Periodic Payment, Principal					364.3
Term Loan | Term Loan B Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,700
Debt Instrument, Periodic Payment, Principal					699.7
Debt Instrument, Periodic Payment, Percentage Of Original Principal	0.25%
Incremental Term Loan Facility
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 798.5
Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	9.125%
Debt Instrument, Periodic Payment, Principal					2,285.1
Debt Instrument, Face Amount	$ 450
Debt Instrument, Fair Value Disclosure					$ 513
Minimum
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.25%
Maximum
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.35%
Base Rate | Revolving Loans And Swingline [Member] | Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					3.50%
Basis spread on variable rate					1.25%
Base Rate | Term Loan | Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					3.50%
Base Rate | Incremental Term Loan Facility | Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					3.50%
Basis spread on variable rate		1.25%			2.00%
Eurodollar Rate | Revolving Loans And Swingline [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum					0.00%
Eurodollar Rate | Revolving Loans And Swingline [Member] | Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Basis spread on variable rate					2.25%
Eurodollar Rate | Term Loan
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum					0.00%
Eurodollar Rate | Incremental Term Loan Facility
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum					0.75%
Eurodollar Rate | Incremental Term Loan Facility | Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Basis spread on variable rate		2.25%			3.00%
Applicable Rate | Revolving Loans And Swingline [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate During Period					2.77%
Applicable Rate | Term Loan
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate During Period					2.77%
Applicable Rate | Incremental Term Loan Facility
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate During Period					3.75%
Remaining Three Years [Member] | Term Loan | Term Loan A Facility [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Periodic Payment, Percentage Of Original Principal	2.50%
First Two Years Following Closing Date [Member] | Term Loan | Term Loan A Facility [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Periodic Payment, Percentage Of Original Principal	1.25%
Debt Instrument, Payment Term	2 years
Line of Credit [Member]
Line of Credit Facility [Line Items]
Gains (Losses) on Extinguishment of Debt, before Write off of Deferred Debt Issuance Cost				72.3	$ 4.5
Gains (Losses) on Extinguishment of Debt				61.3
Write off of Deferred Debt Issuance Cost				$ 11

Other Long-Term Liabilities (De

Other Long-Term Liabilities (Detail) - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Other Liabilities Disclosure [Abstract]
Unrecognized tax benefits	$ 70.6	$ 19.8
Deferred rent	17.2	11.2
Pension and retirement	14.2	8.9
Restructuring	4.2	3.4
Other	9.6	3
Total	$ 115.8	$ 46.3

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Detail)	1 Months Ended		9 Months Ended	12 Months Ended
	Jul. 31, 2016$ / sharesshares	Feb. 28, 2016USD ($)shares	Jul. 03, 2016	Oct. 02, 2016USD ($)shares	Sep. 27, 2015USD ($)shares	Sep. 28, 2014USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $				$ 101,100,000	$ 49,800,000	$ 43,900,000
Restructuring Costs | $				23,100,000
Unamortized compensation expense related to unvested options and restricted stock awards, net of forfeitures | $				$ 102,300,000
Compensation expense related to nonvested restricted stock options, recognition periods				1 year 6 months
Common stock for delivery under awards that have been and may be granted				12,300,000	11,700,000	14,100,000
Stock Option Plan 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares to the shares limit in common stock		4,800,000
Shares limit in common stock		41,800,000
Full value award of shares issued for every one share		2.41
Maximum term of a stock option grant or a stock appreciation right grant				6 years
Stock Option Plan 2008 | Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Grant Awards Limit, Value | $		$ 400,000
Stock Option Plan 2008 | Board of Directors Chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Grant Awards Limit, Value | $		$ 600,000
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
Restricted Stock Units (RSUs) | 2008 Performance Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units authorized under the plan (in shares)	1,000,000
Award vesting period	5 years
Threshold number of trading days for vesting level achievement	20 days
Percentage of Total Award that Vests (no more than)	100.00%
Restricted Stock Units (RSUs) | 2008 Performance Incentive Plan | Performance Level One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price Level (in dollars per share) | $ / shares	$ 50
Number of accelerated shares vested	160,000
Percentage of Total Award that Vests (no more than)	25.00%
Restricted Stock Units (RSUs) | 2008 Performance Incentive Plan | Performance Level Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price Level (in dollars per share) | $ / shares	$ 60
Number of accelerated shares vested	320,000
Percentage of Total Award that Vests (no more than)	50.00%
Restricted Stock Units (RSUs) | 2008 Performance Incentive Plan | Performance Level Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price Level (in dollars per share) | $ / shares	$ 70
Number of accelerated shares vested	500,000
Percentage of Total Award that Vests (no more than)	25.00%

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Awards Activity and Price (Detail) - $ / shares shares in Millions	1 Months Ended	12 Months Ended
	Feb. 28, 2016	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Restricted Stock Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Restricted Stock Awards
Outstanding and Nonvested, Balance		3	3.1	3.1
Granted		1.3	1.3	1.6
Assumed from acquisition		1.9	0.3
Vested		(2.1)	(1.5)	(1.4)
Canceled		(0.5)	(0.2)	(0.2)
Outstanding and Nonvested, Balance		3.6	3	3.1
Weighted- Average Grant Price
Granted		$ 32.15	$ 29.37	$ 24.67
Assumed from acquisition		$ 29.77	$ 33.01
Stock Option Plan 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares to the shares limit in common stock	4.8

Stock-Based Compensation - Perf

Stock-Based Compensation - Performance Incentive Plan Vesting Levels (Details) - 2008 Performance Incentive Plan - Restricted Stock Units (RSUs)	1 Months Ended
	Jul. 31, 2016$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of Total Award That Vests	100.00%
Performance Level One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price Level (in dollars per share)	$ 50
Percentage of Total Award That Vests	25.00%
Performance Level Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price Level (in dollars per share)	$ 60
Percentage of Total Award That Vests	50.00%
Performance Level Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price Level (in dollars per share)	$ 70
Percentage of Total Award That Vests	25.00%

Stock-Based Compensation - Pe60

Stock-Based Compensation - Performance Shares (Details) - Performance stock units - shares shares in Millions	9 Months Ended		12 Months Ended
	Jul. 03, 2016	Jun. 29, 2014	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Vesting percentage relative to net sales			70.00%	40.00%
Vesting percentage relative to earnings per share			30.00%	60.00%
Performance Based Compensation Percentage			225.00%	200.00%
Performance Based Compensation, Shares Awarded as a Percentage of Grants, Peer Group Based		125.00%	120.00%
Performance Units
Outstanding and Nonvested, Balance	0.7	0.6	0.7	0.7	0.6
Granted			1.5	0.3	0.4
Vested			(0.5)	(0.3)	(0.3)
Outstanding and Nonvested, Balance			1.7	0.7	0.7

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity and Stock Appreciation Rights (Detail) - Employee Stock Option And Stock Appreciation Rights - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014	Sep. 30, 2012	Sep. 29, 2013
Stock Options
Outstanding Beginning Balance	0.7	2.7	4.7
Assumed from acquisition		0.2	0.6
Exercised	(0.2)	(2.1)	(1.2)
Forfeited	0	(0.1)	(1.4)
Outstanding Ending Balance	0.5	0.7	2.7
Exercisable stock options	0.4
Exercisable and expected to vest stock options	0.5
Weighted average Exercise Price
Outstanding Beginning Balance	$ 19.60	$ 22.70	$ 22.49
Assumed from acquisition		24.18	20.08
Exercised	21.16	23.83	16.39
Forfeited	21.44	23.90	26.55
Outstanding Ending Balance	18.75	$ 19.60	$ 22.70
Exercisable stock options, Weighted Average Exercise Price	18.24
Exercisable and expected to vest stock options, Weighted Average Exercise Price	$ 18.75
Intrinsic Value
Outstanding, Intrinsic Value	$ 10.7	$ 9.1	$ 7.4		$ 14.7
Exercised, Intrinsic Value		$ 15.8	$ 17
Exercisable stock options, Intrinsic Value	9.8
Exercisable and expected to vest stock options, Intrinsic Value	$ 10.7
Weighted Average Remaining Life
Outstanding, Weighted Average Remaining Life	3 years 6 months	4 years	2 years	1 year 8 months
Exercisable stock options, Weighted Average Remaining Life	3 years 3 months
Exercisable and expected to vest stock options, Weighted Average Remaining Life	3 years 6 months

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option and Stock Appreciation Right Exercise Price Range (Details) - Employee Stock Option And Stock Appreciation Rights shares in Millions	Oct. 02, 2016$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable stock options, Quantity | shares	0.4
Exercisable stock options, Weighted Average Exercise Price | $ / shares	$ 18.24
Outstanding stock options, Quantity | shares	0.5
Outstanding stock options, Weighted Average Exercise Price | $ / shares	$ 18.75
Less than or equal to $20.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable stock options, Quantity | shares	0.3
Exercisable stock options, Weighted Average Exercise Price | $ / shares	$ 14.08
Outstanding stock options, Quantity | shares	0.3
Outstanding stock options, Weighted Average Exercise Price | $ / shares	$ 14.17
Greater than $20.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable stock options, Quantity | shares	0.1
Exercisable stock options, Weighted Average Exercise Price | $ / shares	$ 25.87
Outstanding stock options, Quantity | shares	0.2
Outstanding stock options, Weighted Average Exercise Price | $ / shares	$ 25.60

Employee Benefit Plans (Details

Employee Benefit Plans (Details)	12 Months Ended
	Oct. 02, 2016USD ($)Year	Sep. 27, 2015USD ($)	Sep. 28, 2014USD ($)	Sep. 30, 2012	Oct. 02, 2011
Postemployment Benefits [Abstract]
Maximum annual contribution per employee, percent	50.00%
Minimum age employee may contribute additional percentage of wages | Year	50
Maximum additional contribution allowed after age 50, percent	75.00%
Employer contributions	$ 4,400,000
Fair value of plan assets	4,100,000
Benefit obligations	4,200,000	$ 6,900,000
Unrealized actuarial loss on pension benefits	$ (3,900,000)	$ (300,000)	$ (700,000)
Discount rate assumption	1.60%	2.80%		1.00%	2.10%
Estimated future employer contributions in the next twelve months	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Aggregate Undiscounted Future Minimum Rental Payments (Detail) $ in Millions	Oct. 02, 2016USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 26.4
2,017	24
2,018	20.7
2,019	17.8
2,020	11.5
Thereafter	$ 16.7

Commitments and Contingencies65

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 1998	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Commitments and Contingencies Disclosure [Abstract]
Lease expense		$ 23.7	$ 21.5	$ 23.5
Description of the contingency loss agreement	In November 1998, we signed an agreement with the three former owners of this facility whereby they have 1) reimbursed us for $0.5 million of past costs, 2) assumed responsibility for 90% of all future clean-up costs, and 3) promised to indemnify and protect us against any and all third-party claims relating to the contamination of the facility
Accrued workers' compensation liabilities		$ 1.7	$ 2.3
Allegations description		The complaint alleges, inter alia, that programmable logic devices manufactured and sold by our subsidiary Microsemi - SoC infringe United States Patent Numbers 5,687,325, 6,260,087 and 6,272,646 assigned to Intellectual Ventures II LLC, and seeks damages and other relief at law or in equity as the court deems appropriate
Defendant action		On August 8, 2011, the defendants filed a motion to stay the litigation pending conclusion of reexamination of the patents-in-suit by the United States Patent & Trademark Office.
Decision by court		The Court has not yet decided the motion to transfer or motion to stay. Discovery has not yet commenced and no trial date has been set.

Restructuring and Severance C66

Restructuring and Severance Charges - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Schedule of Status of Facilities by Location [Line Items]
Recorded severance accruals	$ 4.2	$ 3.4
Restructuring and severance charges	60.7	15.4	$ 31.5
Employee Severance
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Reversal of Prior Provision	52
Restructuring, Settlement and Impairment Provisions	55.4
Contract Termination Costs
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Settlement and Impairment Provisions	5.1
Restructuring Reserve, Accrual Adjustment	(0.3)
Other Associated Costs
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Settlement and Impairment Provisions	4.2	4
Other Facilities
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Settlement and Impairment Provisions	64.7
Restructuring Reserve, Accrual Adjustment	(3.9)
Payments for Restructuring	36.2
Restructuring Reserve, Settled without Cash	26.3
Recorded severance accruals	7.5	6.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restructuring Liabilities	3
Other Facilities | Employee Severance
Schedule of Status of Facilities by Location [Line Items]
Restructuring Reserve, Accrual Adjustment	(3.4)
Payments for Restructuring	32.4
Restructuring Reserve, Settled without Cash	22.9
Recorded severance accruals	2.5	2.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restructuring Liabilities	2.9
Other Facilities | Contract Termination Costs
Schedule of Status of Facilities by Location [Line Items]
Payments for Restructuring	2.9
Restructuring Reserve, Settled without Cash	0.5
Recorded severance accruals	4.6	3.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restructuring Liabilities	0
Other Facilities | Other Associated Costs
Schedule of Status of Facilities by Location [Line Items]
Restructuring Reserve, Accrual Adjustment	(0.2)
Payments for Restructuring	0.9
Restructuring Reserve, Settled without Cash	2.9
Recorded severance accruals	0.4	$ 0.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restructuring Liabilities	0.1
Vitesse | Employee Severance
Schedule of Status of Facilities by Location [Line Items]
Restructuring and severance charges	$ 45.6

Restructuring and Severance C67

Restructuring and Severance Charges - Restructuring Activities and Accrued Liabilities in the Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 3.4
Ending Balance	4.2	$ 3.4
Employee Severance
Restructuring Cost and Reserve [Line Items]
Provisions	(55.4)
Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Provisions	(5.1)
Other Associated Costs
Restructuring Cost and Reserve [Line Items]
Provisions	(4.2)	(4)
Other Facilities
Restructuring Cost and Reserve [Line Items]
Beginning Balance	6.2
Provisions	(64.7)
Cash expenditures	(36.2)
Other non-cash settlement	(26.3)
Ending Balance	7.5	6.2
Other Facilities | Employee Severance
Restructuring Cost and Reserve [Line Items]
Beginning Balance	2.9
Cash expenditures	(32.4)
Other non-cash settlement	(22.9)
Ending Balance	2.5	2.9
Other Facilities | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Beginning Balance	3.2
Cash expenditures	(2.9)
Other non-cash settlement	(0.5)
Ending Balance	4.6	3.2
Other Facilities | Other Associated Costs
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0.1
Cash expenditures	(0.9)
Other non-cash settlement	(2.9)
Ending Balance	$ 0.4	$ 0.1

Segment Information - Net Sales

Segment Information - Net Sales by the Originating Geographic Area and Estimated End Market (Detail) $ in Millions	3 Months Ended								12 Months Ended
	Oct. 02, 2016USD ($)	Jul. 03, 2016USD ($)	Apr. 03, 2016USD ($)	Jan. 03, 2016USD ($)	Sep. 27, 2015USD ($)	Jun. 28, 2015USD ($)	Mar. 29, 2015USD ($)	Dec. 28, 2014USD ($)	Oct. 02, 2016USD ($)segment	Sep. 27, 2015USD ($)	Sep. 28, 2014USD ($)
Segment Reporting Disclosure [Line Items]
Number of Reportable Segments | segment									1
Net Sales	$ 450.1	$ 431.4	$ 444.3	$ 329.2	$ 328.8	$ 317.1	$ 296.2	$ 303.5	$ 1,655	$ 1,245.6	$ 1,138.3
Aerospace
Segment Reporting Disclosure [Line Items]
Net Sales									495.4	527.2	472.3
Communication
Segment Reporting Disclosure [Line Items]
Net Sales									$ 618	439.8	401
Defense And Security
Segment Reporting Disclosure [Line Items]
Concentration of credit risk in major customer									30.00%
Net Sales									$ 276.9	11.9	6.6
Industrial
Segment Reporting Disclosure [Line Items]
Net Sales									264.7	266.7	258.4
United States
Segment Reporting Disclosure [Line Items]
Net Sales									628.2	610	604.4
Europe
Segment Reporting Disclosure [Line Items]
Net Sales									$ 222.8	$ 189.8	$ 163.7
Asia
Segment Reporting Disclosure [Line Items]
Concentration of credit risk in major customer								12.00%	18.00%	12.00%	0.00%
Net Sales									$ 749.2	$ 399.7	$ 338.4
Other Geographical [Member]
Segment Reporting Disclosure [Line Items]
Net Sales									$ 54.8	$ 46.1	$ 31.8

Segment Information - Long Live

Segment Information - Long Lived Assets by Geographic Area (Detail) - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 174.9	$ 152.7	$ 148.7
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	119.2	117.6	117.9
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	16.4	13.9	12.2
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	22.6	18.9	16.8
Other Geographic Area [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 16.7	$ 2.3	$ 1.8

Unaudited Selected Quarterly 70

Unaudited Selected Quarterly Financial Data - Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Jan. 03, 2016	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Quarterly Financial Information Disclosure [Abstract]
Net Sales	$ 450.1	$ 431.4	$ 444.3	$ 329.2	$ 328.8	$ 317.1	$ 296.2	$ 303.5	$ 1,655	$ 1,245.6	$ 1,138.3
Cost of sales	168.3	164.5	243.7	141.4	154	145	126.9	135.4	717.9	561.3	526.8
Gross profit	281.8	266.9	200.6	187.8	174.8	172.1	169.3	168.1	937.1	684.3	611.5
Net income (loss)	$ 40.5	$ 115.2	$ (212)	$ 23.7	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ (32.6)	$ 84.6	$ 23.1
Basic earnings (loss) per share	$ 0.36	$ 1.03	$ (1.93)	$ 0.25	$ 0.27	$ 0.16	$ 0.26	$ 0.21	$ (0.31)	$ 0.90	$ 0.25
Diluted earnings (loss) per share	$ 0.35	$ 1	$ (1.93)	$ 0.25	$ 0.26	$ 0.15	$ 0.26	$ 0.21	$ (0.31)	$ 0.88	$ 0.24

VALUATION AND QUALIFYING ACCO71

VALUATION AND QUALIFYING ACCOUNTS (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Allowance for Doubtful Accounts, Current [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 26	$ 22.2	$ 17.8
Charged to costs and expenses	9	3.1	3.1
Charged to other accounts	6.7	0.7	1.3
Deductions- recoveries and write-offs	0	0	0
Balance at end of period	41.7	26	22.2
Tax Valuation Allowance
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	250.6	218.9	210.1
Charged to costs and expenses	35.3	13.3	17.6
Charged to other accounts	170.5	18.4	(8.8)
Deductions- recoveries and write-offs	0	0	0
Balance at end of period	$ 456.4	$ 250.6	$ 218.9