Microsemi (MSCC) 10-K 12 Nov 15 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Nov. 04, 2015	Mar. 27, 2015
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 27, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	MSCC
Entity Registrant Name	MICROSEMI CORP
Entity Central Index Key	310,568
Current Fiscal Year End Date	--09-27
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		96,204,392,000
Entity Public Float			$ 3,341,000

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 27, 2015	Sep. 28, 2014
Current assets:
Cash and cash equivalents	$ 256.4	$ 162.2
Accounts receivable, net of allowances of $26.0 at September 27, 2015 and $22.2 at September 28, 2014	186.9	191.2
Inventories	227.2	205
Deferred income taxes, net	26.2	27.3
Other current assets	39.9	32.9
Total current assets	736.6	618.6
Property and equipment, net	152.7	148.7
Goodwill	1,139.3	885.6
Intangible assets, net	357.8	351.9
Deferred income taxes, net	26.8	23.5
Other assets	36.9	28.1
TOTAL ASSETS	2,450.1	2,056.4
Current liabilities:
Accounts payable	82.3	75.5
Accrued liabilities	86.8	85.7
Current maturity of credit facility	32.5	0
Total current liabilities	201.6	161.2
Credit facility	953.9	693.4
Deferred income taxes	41.1	39.3
Other long-term liabilities	$ 46.3	$ 46.9
Commitments and contingencies (Note 13)
Stockholders' equity:
Preferred stock, $1.00 par value; authorized 1 shares; none issued	$ 0	$ 0
Common stock, $0.20 par value; 250.0 authorized, 95.1 issued and outstanding at September 27, 2015 and 95.6 issued and outstanding at September 28, 2014	19	19.1
Capital in excess of par value of common stock	808.1	799.1
Retained earnings	383.2	298.6
Accumulated other comprehensive income (loss)	(3.1)	(1.2)
Total stockholders' equity	1,207.2	1,115.6
Total liabilities and stockholders' equity	$ 2,450.1	$ 2,056.4

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Sep. 27, 2015	Sep. 28, 2014
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 26	$ 22.2
Preferred stock, par value	$ 1	$ 1
Preferred stock, authorized	1	1
Preferred stock, issued	0	0
Common stock, par value	$ 0.20	$ 0.20
Common stock, authorized	250,000	250,000
Common stock, issued	95,100	95,600
Common stock, outstanding	95,100	95,600

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Income Statement [Abstract]
Net sales	$ 1,245.6	$ 1,138.3	$ 975.9
Cost of sales	561.3	526.8	418.7
Gross profit	684.3	611.5	557.2
Operating expenses:
Selling, general and administrative	249.5	241	202.5
Research and development costs	200.3	192	170.6
Amortization of intangible assets	96.5	92.8	84.8
Restructuring and severance charges	15.4	31.5	9.9
Total operating expenses	561.7	557.3	467.8
Operating income	122.6	54.2	89.4
Interest Income (Expense), Net	(27.3)	(27.8)	(30.2)
Other income (expenses):
Other, net	1.6	(2.5)	(3.1)
Total other expense	(25.7)	(30.3)	(33.3)
Income (loss) before income taxes	96.9	23.9	56.1
Income Tax Expense (Benefit)	12.3	0.8	12.4
Net income (loss)	$ 84.6	$ 23.1	$ 43.7
Earnings (loss) per share:
Basic	$ 0.90	$ 0.25	$ 0.49
Diluted	$ 0.88	$ 0.24	$ 0.48
Weighted-average common shares outstanding:
Basic	94.2	92.9	89.5
Diluted	95.9	94.5	91.3
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Translation adjustment	$ (1.6)	$ (0.5)	$ 0.9
Unrealized actuarial loss on pension benefits	(0.3)	(0.7)	(0.2)
Other comprehensive income (loss)	(1.9)	(1.2)	0.7
Total comprehensive income (loss)	$ 82.7	$ 21.9	$ 44.4

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ 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. 30, 2012		90.3
Balance at Sep. 30, 2012	$ 928.1	$ 18.1	$ 678.9	$ 231.8	$ (0.7)
Proceeds from exercise of stock options (in shares)		1.9
Proceeds from exercise of stock options	25.3	$ 0.4	24.9
Tax withholding on restricted stock units	(0.9)		(0.9)
Grants and cancellations of restricted share awards (in shares)		1.6
Grants and cancellations of restricted share awards	0	$ 0.3	(0.3)
Issuance of stock awards related to acquisition	0		0
Stock-based compensation expense	35.2
Stock-based compensation	35.2
Other comprehensive income, net of tax	0.7				0.7
Net income	43.7			43.7
Balance (in shares) at Sep. 29, 2013		93.8
Balance at Sep. 29, 2013	1,032.1	$ 18.8	737.8	275.5	0
Proceeds from exercise of stock options (in shares)		1.5
Proceeds from exercise of stock options	19.2	$ 0.2	19
Tax withholding on restricted stock units	(1.5)		(1.5)
Grants and cancellations of restricted share awards (in shares)		0.3
Grants and cancellations of restricted share awards	0	$ 0.1	(0.1)
Stock-based compensation expense	43.9
Stock-based compensation	43.9
Other comprehensive income, net of tax	(1.2)				(1.2)
Net income	23.1			23.1
Balance (in shares) at Sep. 28, 2014		95.6
Balance at Sep. 28, 2014	1,115.6	$ 19.1	799.1	298.6	(1.2)
Proceeds from exercise of stock options (in shares)		2.1
Proceeds from exercise of stock options	48.4	$ 0.4	48
Tax withholding on restricted stock units	(18.1)		(18.1)
Grants and cancellations of restricted share awards (in shares)		0.1
Grants and cancellations of restricted share awards	0	$ 0	0
Issuance of stock awards related to acquisition	3.8		3.8
Stock-based compensation expense	49.8
Stock-based compensation	49.8
Other comprehensive income, net of tax	$ (1.9)				(1.9)
Repurchase of outstanding common stock (in shares)	(2.7)	(2.7)
Repurchase of outstanding common stock	$ (75)	$ (0.5)	(74.5)
Net income	84.6			84.6
Balance (in shares) at Sep. 27, 2015		95.1
Balance at Sep. 27, 2015	$ 1,207.2	$ 19	$ 808.1	$ 383.2	$ (3.1)

Consolidated Statement of Cash

Consolidated Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Cash flows from operating activities:
Net income (loss)	$ 84.6	$ 23.1	$ 43.7
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	132.7	125.7	113.7
Provision for doubtful accounts	(0.2)	0.1	(0.4)
Amortization of deferred financing costs	1.6	1.3	3.5
Loss on disposition or impairment of assets	(1.1)	9.8	0
Deferred income taxes	(8)	(21.5)	(9.7)
Valuation allowance on deferred income taxes	13.3	17.6	18.8
Stock based compensation expense	49.8	43.9	35.2
Change in assets and liabilities (net of acquisitions):
Accounts receivable	13.8	5.2	(8.5)
Inventories	11.1	10.3	(2.9)
Other current assets	(2.5)	9.2	(2.2)
Other assets	(7.6)	(1.8)	2.4
Accounts payable	(2.9)	(5.5)	(6.4)
Accrued liabilities	(12.9)	(13.5)	(17.2)
Other long-term liabilities	(2.4)	2.8	(5)
Net cash provided by operating activities	269.3	206.7	165
Cash flows from investing activities:
Purchases of property and equipment	(44.1)	(39.4)	(37.3)
Proceeds from the divestiture or sale of assets	0.6	41	0
Proceeds from the sale of investment	4.2	0	0
Payments for acquisitions, net of cash acquired	(363.9)	(337.6)	0
Net cash used in investing activities	(403.2)	(336)	(37.3)
Cash flows from financing activities:
Repayments of credit facility	(142.7)	(178)	(100)
Credit facility issuance costs	(8.7)	(1.5)	(0.6)
Proceeds from credit facility	425	289.5	277.5
Extinguishment of debt	0	(89.5)	(277.5)
Payments for Repurchase of Common Stock	(75)	0	0
Settlement to terminate capital lease	0	(3)	0
Stock settled tax withholdings	18.1	1.5	0.9
Exercise proceeds from stock awards	47.6	19.1	25.9
Net cash (used in) provided by financing activities	228.1	35.1	(75.6)
Net increase (decrease) in cash and cash equivalents	94.2	(94.2)	52.1
Cash and cash equivalents at beginning of year	162.2	256.4	204.3
Cash and cash equivalents at end of year	256.4	162.2	256.4
Supplemental disclosure of cash flow information Cash paid during the year for:
Interest	27.4	29.2	30.9
Income taxes	$ 3.3	$ 3.9	$ 2.8

Description of business and sum

Description of business and summary of significant accounting policies	12 Months Ended
	Sep. 27, 2015
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 one of the industry's most comprehensive portfolios of semiconductor technology. Our products include high-performance and radiation-hardened analog mixed-signal ICs); field programmable gate arrays; system on chip solutions and application-specific ICs; power management products; timing and synchronization devices and precise time solutions, setting the world's standard for time; voice processing devices; radio frequency solutions; discrete components; 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 we serve include Aerospace, Communications, Defense & Security, and Industrial. Today, Microsemi products are found in applications such as: communications infrastructure systems, both wireless and wired LAN systems, implantable pacemakers and defibrillators, missile systems, military and commercial satellites and aircrafts, oil field equipment and airport security systems. Fiscal Year We report results of operations on the basis of fifty-two and fifty-three week periods. The fiscal years ended on September 27, 2015 , September 28, 2014 , and September 29, 2013 consisted of fifty-two weeks. In referencing a year, we are referring to the fiscal year ended on the Sunday generally 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 September 27, 2015 Investment in marketable securities $ 1.7 $ 1.7 $ — $ — September 28, 2014 Investment in marketable securities $ 4.1 $ 4.1 $ — $ — Interest rate swap liabilities 0.1 — 0.1 — 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 2015 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. 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. 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 or 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 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. Fiscal years 2007 to 2014 generally remain subject to examination by federal and most state tax authorities. In significant foreign jurisdictions, the 2011 to 2014 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. We are currently undergoing an Internal Revenue Service examination as well as certain state examinations. There have been no significant proposed adjustments to date. As of September 27, 2015 , the IRS has raised questions primarily related to transfer pricing. Management believes the Company's position is appropriate and 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 the Company's tax audits are resolved in a manner not consistent with management's expectations, the Company would be required to adjust its provision for income tax in the period such resolution occurs. While the Company believes its reported results are accurate, any significant adjustments could have a material adverse effect on the Company's results of operations, cash flows and financial position if not resolved within 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 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 renminbi. 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 2015 , 2014 and 2013 were calculated as follows (amounts in millions, except per share data): Fiscal Years 2015 2014 2013 BASIC Net income $ 84.6 $ 23.1 $ 43.7 Weighted-average common shares outstanding 94.2 92.9 89.5 Basic earnings per share $ 0.90 $ 0.25 $ 0.49 DILUTED Net income $ 84.6 $ 23.1 $ 43.7 Weighted-average common shares outstanding for basic 94.2 92.9 89.5 Dilutive effect of stock awards 1.7 1.6 1.8 Weighted-average common shares outstanding on a diluted basis 95.9 94.5 91.3 Diluted earnings per share $ 0.88 $ 0.24 $ 0.48 For 2015 , 2014 and 2013 , 0.2 million , 2.8 million and 1.8 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 27% of total net sales in 2015 were in the Defense & Security end market, with a very significant amount of these sales to customers whose principal sales are to the U.S. Government or to subcontractors whose material sales are to the U.S. Government. 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 from international markets represent a significant portion of total net sales. Our net sales to international customers represented 51% of consolidated net sales for 2015 and 47% of consolidated net sales for each of 2014 and 2013 . 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 In February 2013, the FASB issued ASU 2013-04, the objective of which is to provide guidance for the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date. The guidance in the update requires that these arrangements be recorded as the sum of the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. ASU 2013-04 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this ASU did not impact our consolidated financial position, results of operations or cash flows. In July 2013, the FASB issued ASU 2013-11 which requires that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward, with certain exceptions. ASU 2013-11 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this ASU did not impact our consolidated financial position, results of operations or cash flows. In April 2014, the FASB issued ASU 2014-08 which changes the threshold for reporting discontinued operations and adds additional disclosures. The guidance in this ASU updates the definition of discontinued operations to include the disposal of a component or group of components that is disposed of or is classified as held for sale and represents a strategic shift that has (or will have) a major effect on an entity's operations and financial results. ASU 2014-08 is effective prospectively for all disposals of components of an entity that occur with annual periods beginning on or after December 15, 2014, and interim periods therein, with early adoption permitted. We elected to early adopt this ASU and adoption did not impact our consolidated financial position, results of operations or cash flows. In May 2014, the FASB issued 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 issued ASU 2015-14 which delays the effective date of ASU 2014-09 by one year. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and can be adopted either retrospectively to each prior reporting period presented or as a cumulative-effect adjustment as of the date of adoption, with early application permitted as of the original effective date. We are currently assessing the adoption and impact of this ASU on our consolidated financial position and results of operations. In June 2014, the FASB issued ASU 2014-12 which provides guidance on how to account for shared-based payment awards where the terms of the award provide that a performance target that affects vesting could be achieved after the requisite service period. The ASU requires that a performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. ASU 2014-12 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015, and early adoption is permitted. We are currently assessing the impact of this ASU on our consolidated financial position and results of operations. In August 2014, the FASB issued ASU 2014-15 which provides guidance on management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern within one year after the date that the financial statements are issued (or within one year after the date that the financial statements are available to be issued when applicable) and to provide related footnote disclosures. ASU 2014-15 is effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. We are currently assessing the impact of this ASU on our consolidated financial position and results of operations, however, we do not anticipate that adoption of this ASU will impact our consolidated financial position and results of operations. In January 2015, the FASB issued ASU 2015-01 which eliminates from generally accepted accounting principles the concept of extraordinary items. If an event or transaction meets the criteria for extraordinary classification, it is segregated from the results of ordinary operations and is shown as a separate item in the income statement, net of tax. ASU 2015-01 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. We elected to early adopt this ASU and adoption did not impact our consolidated financial position, results of operations or cash flows. In April 2015, the FASB issued ASU 2015-03 whose objective is to simplify the presentation of debt issuance costs by requiring that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of debt liability, consistent with debt discounts and premiums. In August 2015, the FASB issued ASU 2015-15 which clarifies the presentation and subsequent measurement of debt issuance costs associated with lines of credit. These costs may be presented as an asset and amortized ratably over the term of the line of credit arrangement, regardless of whether there were any outstanding borrowings on the line-of-credit agreement. ASU 2015-03 and ASU 2015-15 are effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. We elected to early adopt these ASUs and the adoption resulted in a reclassification of $4.7 million in debt issuance costs from "other assets" to "credit facility" in the consolidated balance sheet as of September 28, 2014. In April 2015, the FASB issued ASU 2015-05 which adds guidance to Subtopic 350-40, Intangibles - Goodwill and Other - Internal-Use Software, which will help entities evaluate when a cloud computing arrangement includes the sale or license of software. ASU 2015-05 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted. We elected to early adopt this ASU retrospectively and adoption did not impact our consolidated financial position, results of operations or cash flows. In July 2015, the FASB issued ASU 2015-11 whose objective is to simplify the subsequent measurement of inventory by using only the lower of cost or net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. ASU 2015-11 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2016. We are currently assessing the adoption and impact of this ASU on our consolidated financial position and results of operations. In September 2015, the FASB issued ASU 2015-16 whose objective is to simplify the accounting for measurement-period adjustments from a business combination. GAAP currently requires that during the measurement period, the acquirer retrospectively adjust provisional amounts recognized at the acquisition date with a corresponding adjustment to goodwill. The acquirer must revise comparative information for prior periods presented in financial statements as needed. ASU 2015-16 eliminates the requirement to retrospectively account for those adjustments. ASU 2015-16 is effective for annual periods beginning after December 15, 2016. We elected to early adopt this ASU retrospectively and adoption did not impact our consolidated financial position, results of operations or cash flows.

Acquisitions

Acquisitions	12 Months Ended
	Sep. 27, 2015
Business Combinations [Abstract]
Acquisitions	Note 2 Acquisitions In April 2015, we acquired Vitesse Semiconductor Corporation ("Vitesse"), which designs and markets a diverse portfolio of high-performance semiconductors, application software, and integrated turnkey systems solutions for carrier, enterprise and Internet of Things ("IoT") networks worldwide. Vitesse products enable the fastest-growing network infrastructure markets including mobile access/IP edge, cloud access and industrial-IoT networking. The consideration for this acquisition was $383.2 million for all the equity interests of Vitesse. We recorded Vitesse'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 preliminary allocation is as follows (amounts in millions): Cash and cash equivalents $ 16.2 Accounts receivable 9.4 Inventories 33.8 Other current assets 4.7 Property and equipment 2.4 Deferred income taxes, net 5.6 Other assets 2.3 Identifiable intangible assets 102.4 Goodwill 252.5 Current liabilities (28.1 ) Long term debt (17.7 ) Other non-current liabilities (0.3 ) Total consideration $ 383.2 As of the acquisition date, the gross contractual amount of acquired accounts receivable of $10.0 million was expected to be fully collected. The valuation of identifiable intangible assets and their estimated useful lives are as follows (dollar amounts in millions): Asset Amount Weighted Average Useful Life (Years) Completed technology $ 87.0 7 Customer relationships 14.4 9 Other 1.0 1 $ 102.4 Valuation methodology The fair value of completed technology was estimated by performing a discounted cash flow analysis using the income approach. This method includes discounting the projected cash flows associated with Vitesse's current products over their expected life. Projected cash flows attributable to the completed technology were discounted to their present value at a rate commensurate with the perceived risk. The valuation of customer relationships was based on the income approach, also taking into account the profit margin a market participant distributor would obtain in selling Vitesse products. The useful lives of customer relationships are estimated based upon customer turnover data and management estimates. Other identifiable intangible assets consisted of backlog and tradename. 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 Vitesse 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. 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 utilized the straight line method of amortization for completed technology, customer relationships and trade name. In November 2013, we acquired Symmetricom, Inc. for consideration of $312.7 million . We acquired Symmetricom for its world-leading source of highly precise timekeeping technologies and solutions that enable next generation data, voice, mobile and video networks and services. In July 2014, we acquired Mingoa, Ltd., a provider of semiconductor IP for hardware accelerated Ethernet OAM and embedded tests and in September 2014, we acquired Centellax, Inc., a supplier of high-speed analog and RF semiconductor products for the optical communications and Ethernet datacom markets. The consideration for these acquisitions was $51.5 million . We acquired all the equity interests of each of these companies. Supplemental pro forma data (unaudited) 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 2014 . The supplemental pro forma data reports actual operating results, adjusted to include the pro forma effect and timing of the impact in cost of goods sold from manufacturing profit in acquired inventory, amortization expense of identified intangible assets, incremental interest expense and the related tax effects of the acquisition. 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 acquisitions into existing operations, engineering groups, sales distribution networks and management structure. Related to our acquisition of Vitesse, products acquired with the Vitesse acquisition amounted to approximately 3% of consolidated net sales for 2015 . The supplemental pro forma information 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. Supplemental pro forma data is as follows (amounts in millions, except per share data): 2015 2014 Net sales $ 1,294.8 $ 1,289.0 Net income (loss) $ 71.8 $ (26.2 ) Earnings per share: Basic $ 0.76 $ (0.28 ) Diluted $ 0.75 $ (0.28 )

Inventories

Inventories	12 Months Ended
	Sep. 27, 2015
Inventory Disclosure [Abstract]
Inventories	Note 3 Inventories Inventories are summarized as follows (amounts in millions): September 27, September 28, Raw materials $ 56.5 $ 55.3 Work in progress 111.7 94.0 Finished goods 59.0 55.7 $ 227.2 $ 205.0 We periodically evaluate the profitability of our various offerings. Should the actual or expected profitability fall below an acceptable threshold, we may decide to stop offering a product, in part to reallocate manufacturing, operations, engineering, sales and support resources to products we expect will generate greater returns. During 2014, our evaluation led us to selectively exit product offerings we believe will continue to lag our overall profitability goals. This resulted in an inventory write-off of $7.9 million . We believe for many of these products, market dynamics dictate price is the primary differentiator rather than our value-added core competencies of power, reliability, security and performance.

Property and Equipment

Property and Equipment	12 Months Ended
	Sep. 27, 2015
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 September 27, September 28, Buildings 20-40 years $ 43.0 $ 40.1 Machinery and equipment 3-10 years 429.1 339.8 Furniture and fixtures 5-10 years 9.8 9.9 Leasehold improvements Shorter of asset life or life of lease 54.1 47.0 536.0 436.8 Accumulated depreciation (393.8 ) (303.8 ) Land 1.9 2.1 Construction in progress 8.6 13.6 $ 152.7 $ 148.7 Depreciation expense was $36.2 million , $32.9 million and $28.8 million in 2015 , 2014 and 2013 , respectively.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, Net	12 Months Ended
	Sep. 27, 2015
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 (amounts in millions): September 27, 2015 September 28, 2014 Life (in years) Gross Carrying Value Accumulated Amortization Gross Carrying Value Accumulated Amortization Amortizable intangible assets Completed technology $ 489.7 $ (251.7 ) $ 402.7 $ (201.3 ) 2 to 15 Customer relationships 316.2 (197.1 ) 301.8 (152.5 ) 4 to 15 Backlog, trade name and other 18.8 (18.1 ) 17.9 (16.7 ) 1 to 5 $ 824.7 $ (466.9 ) $ 722.4 $ (370.5 ) Non-amortizable intangible assets Goodwill $ 1,139.3 $ 885.6 A reconciliation of our goodwill for the years ended September 27, 2015 and September 28, 2014 is as follows (amounts in millions): September 27, 2015 September 28, 2014 Beginning balance $ 885.6 $ 790.2 Additions from acquisitions 253.7 95.4 Ending balance $ 1,139.3 $ 885.6 Amortization of intangible assets included in operating expenses for each of the three fiscal years in the period ended September 27, 2015 is as follows (amounts in millions): 2015 2014 2013 Completed technology $ 50.4 $ 43.9 $ 39.0 Customer relationships 44.6 45.0 42.6 Backlog, trade name and other 1.5 3.9 3.2 $ 96.5 $ 92.8 $ 84.8 Estimated amortization expense in each of the five succeeding years and thereafter is as follows (amounts in millions): 2016 2017 2018 2019 2020 Thereafter $ 100.8 $ 96.6 $ 53.2 $ 30.8 $ 25.6 $ 50.8

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Sep. 27, 2015
Accounts Payable and Accrued Liabilities, Current [Abstract]
Accrued Liabilities	Note 6 Accrued Liabilities Accrued liabilities consisted of the following components (amounts in millions): September 27, September 28, Payroll, bonus and employee benefits $ 33.3 $ 34.3 Deferred revenue 9.7 11.4 Outside services 9.2 9.6 Warranties 6.4 6.9 Commissions 3.8 4.0 Licenses 6.0 1.1 Leases and rent 2.6 0.7 Restructuring and severance 2.5 8.4 Customer deposits 2.2 1.1 Property and sales taxes 1.3 1.1 Income taxes 1.4 1.0 Other 8.4 6.1 $ 86.8 $ 85.7

Income Taxes

Income Taxes	12 Months Ended
	Sep. 27, 2015
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 September 27, 2015 (amounts in millions): 2015 2014 2013 Domestic $ (14.9 ) $ (62.7 ) $ (38.7 ) Foreign 111.8 86.6 94.8 Total $ 96.9 $ 23.9 $ 56.1 The provision for income taxes consisted of the following components for each of the three fiscal years in the period ended September 27, 2015 (amounts in millions): 2015 2014 2013 Current: Federal $ — $ — $ 0.8 State 0.2 0.3 0.8 Foreign 4.2 3.9 3.1 Deferred: Federal 4.6 (6.5 ) 2.3 State — (0.2 ) 1.4 Foreign 3.3 3.3 4.0 $ 12.3 $ 0.8 $ 12.4 We recorded a provision for income taxes of $12.3 million on pretax income of $96.9 million in 2015 compared to a provision for income taxes of $0.8 million on pre-tax income of $23.9 million in 2014, and a provision for income taxes of $12.4 million on pretax income of $56.1 million in 2013. 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 amortization of indefinite lived assets for tax purposes, with an offset in 2014 by the 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 2015 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 it is more likely than not the tax benefits will not be realized in the future. During 2015 and 2014, we increased the valuation allowance by $31.6 million and $8.9 million , respectively. During 2015, this increase was primarily related to continued losses in various jurisdictions and an increase due to deferred tax assets of Vitesse that were not more likely that not realizable as of the acquisition date. During 2014, this increase was primarily related to continued losses in various jurisdictions, which is partially offset by a reduction in Microsemi valuation allowance as a result of net deferred tax liabilities of companies acquired during 2014. We have federal and state net operating losses ("NOLs") of $366.4 million and $253.1 million , respectively, that begin expiring in 2018 and 2016, respectively. Of the total NOL carryforward, $51.6 million related to the excess tax benefit from employee stock compensation and stockholders' equity will increase by $51.6 million if and when such excess tax benefits are ultimately realized. We have foreign NOLs of $283.7 million that begin expiring in 2016. We have federal and state research and experimentation credits of $52.3 million and $91.9 million , respectively, that begin expiring in 2017 and 2016, respectively. We have foreign research and experimentation credits of $81.9 million that begin expiring in 2017 and incentive deductions of $16.2 million that carry forward indefinitely. We have federal foreign tax credits of $4.7 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 $8.9 million that began expiring in 2015. The utilization of NOLs and credits acquired through an acquisition may be subject to limitations due to change in control. No provision has been made for future income taxes on undistributed earnings of foreign operations (except for 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 2015 and 2014, these undistributed earnings aggregated $471.2 million and $430.4 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 September 27, 2015 (amounts in millions): 2015 2014 2013 Tax computed at federal statutory rate $ 33.9 $ 8.4 $ 19.6 State taxes, net of federal impact (2.1 ) (1.1 ) (1.6 ) Foreign income taxed at different rates (33.1 ) (24.7 ) (20.5 ) Tax credits and incentives (5.1 ) (2.8 ) (5.4 ) Stock award compensation 1.3 1.2 0.2 Unrecognized tax benefits 3.7 1.4 (0.4 ) U.S. tax on foreign income 1.3 4.1 1.4 Income tax return to provision — (0.2 ) (0.9 ) Non-deductible permanent items 0.9 0.9 0.2 Pre-acquisition loss carry forwards — (11.4 ) — Expiration of tax attributes — 2.9 — Foreign declared dividend (0.5 ) 3.6 — Withholding taxes (0.3 ) 0.3 0.7 Other differences, net (1.0 ) 0.6 0.3 Valuation allowance 13.3 17.6 18.8 $ 12.3 $ 0.8 $ 12.4 The tax effected deferred tax assets (liabilities) are comprised of the following components (amounts in millions): September 27, September 28, 2014 Accounts receivable, net $ 1.9 $ 1.2 Inventories 17.5 14.5 Accrued employee benefit expenses 8.4 8.8 Net operating losses 164.6 149.6 Tax credits and incentives 153.5 144.2 Accrued other expenses 9.7 11.4 Deferred equity compensation 18.9 16.7 Property and equipment, net 13.8 3.1 Other assets 11.4 11.8 Total deferred tax assets 399.7 361.3 Intangible assets (137.1 ) (127.2 ) Foreign declared dividend — (3.6 ) Total deferred tax liabilities (137.1 ) (130.8 ) Less valuation allowance (250.6 ) (218.9 ) $ 12.0 $ 11.6 A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (amounts in millions): September 27, September 28, September 29, 2013 Beginning gross unrecognized tax benefits $ 97.7 $ 69.6 $ 58.0 Additions based on tax positions related to the current year 3.5 2.4 3.2 Additions based on current year acquisitions 16.2 28.9 — Additions based on tax positions of prior years 4.8 0.4 12.9 Reductions based on tax positions of prior years — — (2.8 ) Reductions for lapses and settlements (0.4 ) (3.6 ) (1.7 ) Ending gross unrecognized tax benefit $ 121.8 $ 97.7 $ 69.6 We recognize interest and penalties accrued related to unrecognized tax benefits in tax expense. During the years ended September 27, 2015 , September 28, 2014 , and September 29, 2013 , we recognized $0.7 million , $0.7 million and $0.1 million , respectively. The cumulative interest and penalties at September 27, 2015 and September 28, 2014 were $7.4 million and $6.6 million , respectively. Unrecognized tax benefits of $62.5 million (including interest) at September 27, 2015 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 $28.3 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 2014 generally remain subject to examination by federal and most state tax authorities. In significant foreign jurisdictions, the 2011 to 2014 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. We are currently undergoing an Internal Revenue Service examination as well as certain state examinations. There have been no significant proposed adjustments to date. As of September 27, 2015 , the IRS has raised questions primarily related to transfer pricing. Management believes the Company's position is appropriate and 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 the Company's tax audits are resolved in a manner not consistent with management's expectations, the Company would be required to adjust its provision for income tax in the period such resolution occurs. While the Company believes its reported results are accurate, any significant adjustments could have a material adverse effect on the Company's results of operations, cash flows and financial position if not resolved within expectations.

Credit Agreement

Credit Agreement	12 Months Ended
	Sep. 27, 2015
Debt Disclosure [Abstract]
Credit Agreement	Note 8 Credit Agreement Credit Agreement On March 31, 2015, we entered into Amendment No. 6 to our existing Amended and Restated Credit Agreement dated as of October 13, 2011 (such Amended and Restated Credit Agreement as further amended and supplemented prior to March 31, 2015, the "Existing Credit Agreement"; and as amended by Amendment No. 6, the “Amended Credit Agreement"), with Bank of America, N.A., as administrative agent and collateral agent. Pursuant to the Existing Credit Agreement, certain lenders provided first lien credit facilities, consisting of a term loan facility and a revolving credit facility. Amendment No. 6 provided for, among other things, (1) certain amendments to the provisions relating to incremental credit facilities to (i) permit up to $325.0 million of incremental term loan facilities to be in the form of term A loans, and (ii) permit the incremental revolving commitment capacity to be increased by the amount of all prior voluntary terminations of revolving commitments, (2) an amendment to the definition of "change of control" in the Existing Credit Agreement to remove the "continuing director" prong (clause (b)) from such defined term, and (3) certain amendments related to the acquisition of Vitesse. In connection with Amendment No. 6, Bank of America, N.A., replaced Royal Bank of Canada as administrative agent and as collateral agent under the Amended Credit Agreement. On April 28, 2015, we entered into an Incremental Joinder Agreement with respect to an incremental term A loan of $325.0 million and incremental revolving commitments of $225.0 million under our Amended Credit Agreement (as supplemented by the Incremental Joinder Agreement, the "Credit Agreement"). The term A loan and incremental revolving commitments each mature in August 2019. Beginning with the quarter ending September 27, 2015, and each quarter thereafter, we are required to make quarterly principal payments of $8.1 million on term A loan borrowings. The incremental term A loan and incremental revolving commitments initially bear interest at an interest rate margin of 2.00% for Eurodollar Rate loans and 1.00% for Base Rate loans, and the incremental revolving commitments are subject to an undrawn commitment fee of 0.35% . The interest rate margins and commitment fee are subject to step-downs based on our Consolidated Leverage Ratio (as defined in the Credit Agreement). On April 28, 2015, we borrowed $325.0 million of incremental term A loan and $100.0 million under incremental revolving commitments to fund the acquisition of Vitesse, to repay a portion of term B loan principal, and for general corporate purposes. Our term B loan facility matures in February 2020 and as of September 27, 2015 , there are no scheduled principal repayments until the maturity date. The Credit Agreement stipulates an annual principal payment of a percentage of Excess Cash Flow ("ECF") (as defined in the Credit Agreement). The first ECF application date was measured as of the end of fiscal year 2015 and the ECF percentage will be 50% if the Consolidated Leverage Ratio as of the last day of the fiscal year is equal to or greater than 3.00 to 1.00 and 0% otherwise. Under our Credit Agreement, we may borrow under a "Base Rate" which approximates the prime rate plus an applicable margin or "Eurodollar Rate" which approximates LIBOR plus an applicable margin. For term B loans, Eurodollar Rate loans are also subject to a Eurodollar Floor. At September 27, 2015 , the principal amounts outstanding were Eurodollar Rate loans and interest rate information as of September 27, 2015 , were as follows (amounts in millions, except percentages): Principal Outstanding Base Rate Base Rate Margin Eurodollar Rate Margin Eurodollar Floor Applicable Rate Revolving and swingline loans $ 100.0 3.25 % 1.00 % 2.00 % — % 2.15 % Term A loan $ 325.0 3.25 % 1.00 % 2.00 % — % 2.15 % Term B loan $ 573.0 3.25 % 1.50 % 2.50 % 0.75 % 3.25 % Debt issuance costs recorded as a reduction to principal outstanding in the consolidated balance sheets were $4.7 million as of September 28, 2014 and $11.7 million as of September 27, 2015 . The fair value of our outstanding loans was $995.9 million at September 27, 2015 and $693.0 million at September 28, 2014 . We classify this valuation as a Level 2 fair value measurement and determined the fair value based on a mid-market valuation reported to us by a participant in the credit facility. Our Credit Agreement includes financial covenants requiring a maximum 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 September 27, 2015 . Interest Rate Swap Agreement In connection with our Credit Agreement in 2011, we entered into interest rate swap agreements for the purpose of minimizing the variability of cash flows in the interest rate payments of our variable rate borrowings. The cash flows received under the interest rate swap agreements are expected to offset the change in cash flows associated with LIBOR rate borrowings between the effective and maturity dates of the swaps. Our last interest rate swap agreement expired in January 2015 . We classified our interest rate swap balance as a Level 2 fair value measurement. We determined the fair value of our interest rate swap agreements based on mid-market valuations reported to us by the counterparty to the swap agreements. We reflect the change in fair value of the swaps through other income (expense), net and recorded income of $0.6 million in 2014 and income of $1.3 million in 2013.

Other Long-Term Liabilities

Other Long-Term Liabilities	12 Months Ended
	Sep. 27, 2015
Other Liabilities Disclosure [Abstract]
Other Long-Term Liabilities	Note 9 Other Long-Term Liabilities Other long-term liabilities consisted of (amounts in millions): September 27, September 28, Unrecognized tax benefits $ 19.8 $ 17.4 Deferred rent 11.2 13.7 Pension and retirement 8.9 8.9 Restructuring 3.4 3.8 Other 3.0 3.1 Total $ 46.3 $ 46.9

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Sep. 27, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Note 10 Stock-Based Compensation Stock Based Compensation In February 2014, our stockholders approved an amendment to the Microsemi Corporation 2008 Performance Incentive Plan (the "2008 Plan"). The amendment a) increased the share limit by an additional 4.8 million shares so that the amended aggregate share limit for the 2008 Plan is 33.3 million shares; b) 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 2019. The 2008 Plan's termination date of December 5, 2021 remained unchanged, as did the number of shares counted against the share limit for every one share issued in connection with a full-value award, which remained 2.41 . 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 that are 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 that are 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 $49.8 million in 2015 , $43.9 million in 2014 and $35.2 million in 2013 . At September 27, 2015 , unamortized compensation expense related to unvested stock awards was $56.3 million . The weighted average period over which compensation expense related to these grants will be recognized is 1.4 years . Remaining share-units available for grant, assuming the issuance of performance units at target, at September 27, 2015 , September 28, 2014 and September 29, 2013 under the 2008 Plan were 11.7 million , 14.1 million and 12.2 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 30, 2012 2.7 Granted 1.9 $ 20.39 Vested (1.4 ) Forfeited (0.1 ) 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 In connection with the acquisition Vitesse in 2015, we assumed restricted shares and converted them to Microsemi awards in accordance with the merger agreement. Performance Stock Units 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. Monte Carlo valuation inputs included grant date, performance period, our historical volatility, peer group volatility and risk free interest rate.Vesting of performance units issued in 2013, 2014 and 2015 contain a market condition and the Monte Carlo simulation incorporates estimates of the potential outcomes of the market condition on the fair value date of each award. Performance stock units granted in 2013 are eligible to vest based on our achievement of net sales and earnings per share (subject to certain adjustments) levels for 2013, 2014 and 2015. For these performance stock units, 25% of each performance-based award opportunity will be subject to the net sales metric for the performance period and 75% will be subject to the earnings per share metric for the performance period. The maximum percentage is further adjusted by our total shareholder return relative to a peer group selected by the Compensation Committee, up to a maximum of 125% . Performance units granted in 2014 and 2015 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 the 2014 grants include our fiscal years 2014, 2015 and 2016 and the performance period for the 2015 grants include our fiscal years 2015, 2016 and 2017. A 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 grant, the maximum adjustment is 150% . Activity and price information related to performance units are as follows (quantity reported at target and in millions): Quantity Outstanding at September 30, 2012 0.4 Granted 0.4 Vested (0.2 ) 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 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 30, 2012 7.0 $ 20.26 $ 21.6 2.5 Exercised (1.9 ) $ 14.16 $ 17.0 Forfeited (0.4 ) $ 24.33 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 Exercisable at September 27, 2015 0.6 $ 19.13 $ 7.5 3.6 Exercisable and expected to vest after September 27, 2015 0.7 $ 19.60 $ 9.1 4.0 In connection with the acquisition Symmetricom 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 September 27, 2015 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 0.4 $ 14.18 0.4 $ 14.39 Greater than $20.00 0.2 $ 27.36 0.3 $ 25.91 0.6 $ 19.13 0.7 $ 19.60 Weighted-average fair value and weighted-average assumptions used in the calculation of compensation expense for assumed grants in 2014 and 2015 are as follows. There were no stock options or stock appreciation rights granted or assumed in 2013. Fair Value Risk Free Rate Expected Dividend Yield Expected Life (Years) Expected Volatility September 28, 2014 $ 20.08 0.5 % — % 2.7 31.0 % September 27, 2015 $ 24.18 0.1 % — % 0.7 36.6 %

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Sep. 27, 2015
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 2015 , employer contributions were $3.7 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 a pension plan in Germany related to an acquisition in 2012 that covers 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 this plan. The 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. As of September 27, 2015 , the fair value of plan assets was $4.3 million and benefit obligations were $6.7 million . During 2014, we recorded an unrealized actuarial loss on pension benefits of $0.3 million in other comprehensive income due to a reduction in the discount rate assumption used to determine benefit obligations from 3.2% to 2.1% . There are no employer contributions expected in the next twelve months.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Sep. 27, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 13 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): 2016 2017 2018 2019 2020 Thereafter $ 19.8 $ 17.1 $ 15.1 $ 13.5 $ 12.2 $ 10.6 Lease expense charged to income was $21.5 million in 2015 , $23.5 million in 2014 and $20.2 million in 2013 . Contingencies We are generally self-insured for losses and liabilities related to workers’ compensation and employer’s liability insurance. Accrued workers’ compensation liability was $2.3 million and $1.9 million at September 27, 2015 and September 28, 2014 , 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.

Stock Repurchase Program

Stock Repurchase Program	12 Months Ended
	Sep. 27, 2015
Equity [Abstract]
Stock Repurchase Program	Note 12 Stock Repurchase Program On September 9, 2014, Microsemi Corporation's Board of Directors authorized the repurchase of up to $100.0 million of the Company's common stock before September 30, 2016. On July 21, 2015, Microsemi Corporation's Board of Directors authorized a new stock repurchase program for the repurchase of up to an additional $100.0 million of the Company's common stock before July 31, 2017. Repurchases under either authorization may be made in the open market or through privately negotiated transactions and may also be made under a Rule 10b5-1 plan. The number of shares to repurchase and the timing of such repurchases will be based on several factors, including the price of the Company's common stock, potential alternate and general market and business conditions. During the twelve months ended September 27, 2015 , under the September 9, 2014 authorization, the Company repurchased 2.7 million shares for $75.0 million at an average price of $28.03 under the program. Repurchased shares were retired and returned to authorized shares. Under the existing board authorizations, $125.0 million of common stock may still be repurchased.

Restructuring and Severance Cha

Restructuring and Severance Charges	12 Months Ended
	Sep. 27, 2015
Restructuring and Related Activities [Abstract]
Restructuring and Severance Charges	Note 14 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 28, 2014 $ 4.1 $ 8.2 $ — $ 12.3 Assumed from acquisition 0.1 — — 0.1 Provisions 10.6 2.6 3.9 17.1 Reversal of prior provision (0.6 ) (1.1 ) — (1.7 ) Cash expenditures (11.3 ) (5.9 ) (2.2 ) (19.5 ) Other non-cash settlement — (0.6 ) (1.6 ) (2.2 ) Balance at September 27, 2015 $ 2.9 $ 3.2 $ 0.1 $ 6.2 We recorded net provisions for employee severance of $10.0 million for 2015, of which $2.9 million related to actions following our acquisition of Vitesse. Employee severance covered approximately 250 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 $2.6 million for 2015, primarily for the fair value at the cease-use date of operating lease liabilities for space we have exited. Facilities consisted of manufacturing sites, as well as sales, engineering and administrative space. We recorded a $1.1 million reversal of prior provision related to a facility lease termination that was settled at an amount less than estimated. We recorded provisions for other associated costs for restructuring of $3.9 million for 2015, which consisted of facility and equipment impairments and facility relocation costs.

Segment Information

Segment Information	12 Months Ended
	Sep. 27, 2015
Segment Reporting [Abstract]
Segment Information	Note 15 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, Communications, Defense & Security, 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): 2015 2014 2013 United States $ 610.0 $ 604.4 $ 514.6 Europe 189.8 163.7 142.3 Asia 399.7 338.4 292.6 Other 46.1 31.8 26.4 Total $ 1,245.6 $ 1,138.3 $ 975.9 Aerospace $ 191.4 $ 169.6 $ 187.0 Communications 451.7 407.6 278.1 Defense & Security 335.8 302.7 306.3 Industrial 266.7 258.4 204.5 Total $ 1,245.6 $ 1,138.3 $ 975.9 As a percentage of consolidated net sales, customers with a ship-to location in Hong Kong totaled 12% in 2015 and there were no countries outside the United States exceeding 10% in 2014 and 2013. 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): 2015 2014 2013 United States $ 117.6 $ 117.9 $ 100.7 Europe 13.9 12.2 12.6 Asia 18.9 16.8 10.2 Other 2.3 1.8 1.7 Total $ 152.7 $ 148.7 $ 125.2

Unaudited Selected Quarterly Fi

Unaudited Selected Quarterly Financial Data	12 Months Ended
	Sep. 27, 2015
Quarterly Financial Information Disclosure [Abstract]
Unaudited Selected Quarterly Financial Data	Note 16 Unaudited Selected Quarterly Financial Data Selected quarterly financial data are as follows (amounts in millions, except earnings per share): Quarters ended in fiscal year 2015 September 27, June 28, March 29, December 28, Net sales $ 328.8 $ 317.1 $ 296.2 $ 303.5 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 Quarters ended in fiscal year 2014 September 28, June 29, March 30, December 29, Net sales $ 303.3 $ 292.3 $ 287.0 $ 255.7 Gross profit $ 171.0 $ 153.6 $ 148.6 $ 138.3 Net income (loss) $ 32.8 $ (4.3 ) $ (6.8 ) $ 1.4 Basic earnings (loss) per share $ 0.35 $ (0.05 ) $ (0.07 ) $ 0.02 Diluted earnings (loss) per share $ 0.34 $ (0.05 ) $ (0.07 ) $ 0.02

Subsequent Event

Subsequent Event	12 Months Ended
	Sep. 27, 2015
Subsequent Events [Abstract]
Subsequent Event	Note 17 Subsequent Event On October 30, 2015, we announced a proposal to acquire PMC-Sierra, Inc. ("PMC") in a cash and stock transaction. Under the terms of our proposal, PMC shareholders would receive $9.04 in cash and 0.0771 x of a Microsemi common share for each PMC common share held at the close of the transaction. The implied enterprise value is $2.3 billion , net of PMC’s net cash balance as of September 27, 2015. On November 1, 2015, PMC announced its board of directors had determined our proposal was not superior to an existing arrangement between PMC and Skyworks Solutions, Inc. ("Skyworks"). On November 2, 2015, we issued a press release reiterating the benefits of our proposal. On November 10, 2015, we issued a press release announcing that we had been informed that PMC's board of directors had deemed our reiterated proposal, which we submitted on November 9, 2015, a "Superior Proposal" under the terms of PMC's existing agreement with Skyworks, and that PMC has given written notice to Skyworks of its intent to approve or recommend the Microsemi proposal. As a result, PMC will be entitled to approve or recommend the Microsemi proposal if Skyworks does not make, within three business days following the receipt of the notice, a proposal that would cause the proposal received from Microsemi to no longer constitute a "Superior Proposal."

VALUATION AND QUALIFYING ACCOUN

VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Sep. 27, 2015
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 Tax valuation allowance September 29, 2013 $ 196.1 $ 18.8 $ (4.8 ) $ — $ 210.1 September 28, 2014 $ 210.1 $ 17.6 $ (8.8 ) $ — $ 218.9 September 27, 2015 $ 218.9 $ 13.3 $ 18.4 $ — $ 250.6

Description of business and s25

Description of business and summary of significant accounting policies (Policies)	12 Months Ended
	Sep. 27, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Fiscal Year	We report results of operations on the basis of fifty-two and fifty-three week periods. The fiscal years ended on September 27, 2015 , September 28, 2014 , and September 29, 2013 consisted of fifty-two weeks. In referencing a year, we are referring to the fiscal year ended on the Sunday generally 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.
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. 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 or 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 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. Fiscal years 2007 to 2014 generally remain subject to examination by federal and most state tax authorities. In significant foreign jurisdictions, the 2011 to 2014 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. We are currently undergoing an Internal Revenue Service examination as well as certain state examinations. There have been no significant proposed adjustments to date.
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 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 renminbi.
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 27% of total net sales in 2015 were in the Defense & Security end market, with a very significant amount of these sales to customers whose principal sales are to the U.S. Government or to subcontractors whose material sales are to the U.S. Government. 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 from international markets represent a significant portion of total net sales. Our net sales to international customers represented 51% of consolidated net sales for 2015 and 47% of consolidated net sales for each of 2014 and 2013 . 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	In February 2013, the FASB issued ASU 2013-04, the objective of which is to provide guidance for the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date. The guidance in the update requires that these arrangements be recorded as the sum of the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. ASU 2013-04 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this ASU did not impact our consolidated financial position, results of operations or cash flows. In July 2013, the FASB issued ASU 2013-11 which requires that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward, with certain exceptions. ASU 2013-11 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this ASU did not impact our consolidated financial position, results of operations or cash flows. In April 2014, the FASB issued ASU 2014-08 which changes the threshold for reporting discontinued operations and adds additional disclosures. The guidance in this ASU updates the definition of discontinued operations to include the disposal of a component or group of components that is disposed of or is classified as held for sale and represents a strategic shift that has (or will have) a major effect on an entity's operations and financial results. ASU 2014-08 is effective prospectively for all disposals of components of an entity that occur with annual periods beginning on or after December 15, 2014, and interim periods therein, with early adoption permitted. We elected to early adopt this ASU and adoption did not impact our consolidated financial position, results of operations or cash flows. In May 2014, the FASB issued 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 issued ASU 2015-14 which delays the effective date of ASU 2014-09 by one year. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and can be adopted either retrospectively to each prior reporting period presented or as a cumulative-effect adjustment as of the date of adoption, with early application permitted as of the original effective date. We are currently assessing the adoption and impact of this ASU on our consolidated financial position and results of operations. In June 2014, the FASB issued ASU 2014-12 which provides guidance on how to account for shared-based payment awards where the terms of the award provide that a performance target that affects vesting could be achieved after the requisite service period. The ASU requires that a performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. ASU 2014-12 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015, and early adoption is permitted. We are currently assessing the impact of this ASU on our consolidated financial position and results of operations. In August 2014, the FASB issued ASU 2014-15 which provides guidance on management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern within one year after the date that the financial statements are issued (or within one year after the date that the financial statements are available to be issued when applicable) and to provide related footnote disclosures. ASU 2014-15 is effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. We are currently assessing the impact of this ASU on our consolidated financial position and results of operations, however, we do not anticipate that adoption of this ASU will impact our consolidated financial position and results of operations. In January 2015, the FASB issued ASU 2015-01 which eliminates from generally accepted accounting principles the concept of extraordinary items. If an event or transaction meets the criteria for extraordinary classification, it is segregated from the results of ordinary operations and is shown as a separate item in the income statement, net of tax. ASU 2015-01 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. We elected to early adopt this ASU and adoption did not impact our consolidated financial position, results of operations or cash flows. In April 2015, the FASB issued ASU 2015-03 whose objective is to simplify the presentation of debt issuance costs by requiring that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of debt liability, consistent with debt discounts and premiums. In August 2015, the FASB issued ASU 2015-15 which clarifies the presentation and subsequent measurement of debt issuance costs associated with lines of credit. These costs may be presented as an asset and amortized ratably over the term of the line of credit arrangement, regardless of whether there were any outstanding borrowings on the line-of-credit agreement. ASU 2015-03 and ASU 2015-15 are effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. We elected to early adopt these ASUs and the adoption resulted in a reclassification of $4.7 million in debt issuance costs from "other assets" to "credit facility" in the consolidated balance sheet as of September 28, 2014. In April 2015, the FASB issued ASU 2015-05 which adds guidance to Subtopic 350-40, Intangibles - Goodwill and Other - Internal-Use Software, which will help entities evaluate when a cloud computing arrangement includes the sale or license of software. ASU 2015-05 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted. We elected to early adopt this ASU retrospectively and adoption did not impact our consolidated financial position, results of operations or cash flows. In July 2015, the FASB issued ASU 2015-11 whose objective is to simplify the subsequent measurement of inventory by using only the lower of cost or net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. ASU 2015-11 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2016. We are currently assessing the adoption and impact of this ASU on our consolidated financial position and results of operations. In September 2015, the FASB issued ASU 2015-16 whose objective is to simplify the accounting for measurement-period adjustments from a business combination. GAAP currently requires that during the measurement period, the acquirer retrospectively adjust provisional amounts recognized at the acquisition date with a corresponding adjustment to goodwill. The acquirer must revise comparative information for prior periods presented in financial statements as needed. ASU 2015-16 eliminates the requirement to retrospectively account for those adjustments. ASU 2015-16 is effective for annual periods beginning after December 15, 2016. We elected to early adopt this ASU retrospectively and adoption did not impact our consolidated financial position, results of operations or cash flows.

Description of business and s26

Description of business and summary of significant accounting policies (Tables)	12 Months Ended
	Sep. 27, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Earnings Per Share	Earnings per share for 2015 , 2014 and 2013 were calculated as follows (amounts in millions, except per share data): Fiscal Years 2015 2014 2013 BASIC Net income $ 84.6 $ 23.1 $ 43.7 Weighted-average common shares outstanding 94.2 92.9 89.5 Basic earnings per share $ 0.90 $ 0.25 $ 0.49 DILUTED Net income $ 84.6 $ 23.1 $ 43.7 Weighted-average common shares outstanding for basic 94.2 92.9 89.5 Dilutive effect of stock awards 1.7 1.6 1.8 Weighted-average common shares outstanding on a diluted basis 95.9 94.5 91.3 Diluted earnings per share $ 0.88 $ 0.24 $ 0.48

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Sep. 27, 2015
Business Combinations [Abstract]
Schedule of Business Acquisitions by Acquisition, Contingent Consideration	We recorded Vitesse'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 preliminary allocation is as follows (amounts in millions): Cash and cash equivalents $ 16.2 Accounts receivable 9.4 Inventories 33.8 Other current assets 4.7 Property and equipment 2.4 Deferred income taxes, net 5.6 Other assets 2.3 Identifiable intangible assets 102.4 Goodwill 252.5 Current liabilities (28.1 ) Long term debt (17.7 ) Other non-current liabilities (0.3 ) Total consideration $ 383.2
Schedule of Acquired Finite-Lived Intangible Assets by Major Class	The valuation of identifiable intangible assets and their estimated useful lives are as follows (dollar amounts in millions): Asset Amount Weighted Average Useful Life (Years) Completed technology $ 87.0 7 Customer relationships 14.4 9 Other 1.0 1 $ 102.4
Business Acquisition, Pro Forma Information	Supplemental pro forma data is as follows (amounts in millions, except per share data): 2015 2014 Net sales $ 1,294.8 $ 1,289.0 Net income (loss) $ 71.8 $ (26.2 ) Earnings per share: Basic $ 0.76 $ (0.28 ) Diluted $ 0.75 $ (0.28 )

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Sep. 27, 2015
Inventory Disclosure [Abstract]
Inventories	Inventories are summarized as follows (amounts in millions): September 27, September 28, Raw materials $ 56.5 $ 55.3 Work in progress 111.7 94.0 Finished goods 59.0 55.7 $ 227.2 $ 205.0

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Sep. 27, 2015
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 September 27, September 28, Buildings 20-40 years $ 43.0 $ 40.1 Machinery and equipment 3-10 years 429.1 339.8 Furniture and fixtures 5-10 years 9.8 9.9 Leasehold improvements Shorter of asset life or life of lease 54.1 47.0 536.0 436.8 Accumulated depreciation (393.8 ) (303.8 ) Land 1.9 2.1 Construction in progress 8.6 13.6 $ 152.7 $ 148.7

Goodwill and Intangible Asset30

Goodwill and Intangible Assets, Net (Tables)	12 Months Ended
	Sep. 27, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and intangible assets, net consisted of the following components (amounts in millions): September 27, 2015 September 28, 2014 Life (in years) Gross Carrying Value Accumulated Amortization Gross Carrying Value Accumulated Amortization Amortizable intangible assets Completed technology $ 489.7 $ (251.7 ) $ 402.7 $ (201.3 ) 2 to 15 Customer relationships 316.2 (197.1 ) 301.8 (152.5 ) 4 to 15 Backlog, trade name and other 18.8 (18.1 ) 17.9 (16.7 ) 1 to 5 $ 824.7 $ (466.9 ) $ 722.4 $ (370.5 ) Non-amortizable intangible assets Goodwill $ 1,139.3 $ 885.6
Reconciliation of Goodwill	A reconciliation of our goodwill for the years ended September 27, 2015 and September 28, 2014 is as follows (amounts in millions): September 27, 2015 September 28, 2014 Beginning balance $ 885.6 $ 790.2 Additions from acquisitions 253.7 95.4 Ending balance $ 1,139.3 $ 885.6
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 September 27, 2015 is as follows (amounts in millions): 2015 2014 2013 Completed technology $ 50.4 $ 43.9 $ 39.0 Customer relationships 44.6 45.0 42.6 Backlog, trade name and other 1.5 3.9 3.2 $ 96.5 $ 92.8 $ 84.8
Estimated Amortization Expense	Estimated amortization expense in each of the five succeeding years and thereafter is as follows (amounts in millions): 2016 2017 2018 2019 2020 Thereafter $ 100.8 $ 96.6 $ 53.2 $ 30.8 $ 25.6 $ 50.8

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Sep. 27, 2015
Accounts Payable and Accrued Liabilities, Current [Abstract]
Components of Accrued Liabilities	Accrued liabilities consisted of the following components (amounts in millions): September 27, September 28, Payroll, bonus and employee benefits $ 33.3 $ 34.3 Deferred revenue 9.7 11.4 Outside services 9.2 9.6 Warranties 6.4 6.9 Commissions 3.8 4.0 Licenses 6.0 1.1 Leases and rent 2.6 0.7 Restructuring and severance 2.5 8.4 Customer deposits 2.2 1.1 Property and sales taxes 1.3 1.1 Income taxes 1.4 1.0 Other 8.4 6.1 $ 86.8 $ 85.7

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Sep. 27, 2015
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 September 27, 2015 (amounts in millions): 2015 2014 2013 Domestic $ (14.9 ) $ (62.7 ) $ (38.7 ) Foreign 111.8 86.6 94.8 Total $ 96.9 $ 23.9 $ 56.1
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 September 27, 2015 (amounts in millions): 2015 2014 2013 Current: Federal $ — $ — $ 0.8 State 0.2 0.3 0.8 Foreign 4.2 3.9 3.1 Deferred: Federal 4.6 (6.5 ) 2.3 State — (0.2 ) 1.4 Foreign 3.3 3.3 4.0 $ 12.3 $ 0.8 $ 12.4
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 September 27, 2015 (amounts in millions): 2015 2014 2013 Tax computed at federal statutory rate $ 33.9 $ 8.4 $ 19.6 State taxes, net of federal impact (2.1 ) (1.1 ) (1.6 ) Foreign income taxed at different rates (33.1 ) (24.7 ) (20.5 ) Tax credits and incentives (5.1 ) (2.8 ) (5.4 ) Stock award compensation 1.3 1.2 0.2 Unrecognized tax benefits 3.7 1.4 (0.4 ) U.S. tax on foreign income 1.3 4.1 1.4 Income tax return to provision — (0.2 ) (0.9 ) Non-deductible permanent items 0.9 0.9 0.2 Pre-acquisition loss carry forwards — (11.4 ) — Expiration of tax attributes — 2.9 — Foreign declared dividend (0.5 ) 3.6 — Withholding taxes (0.3 ) 0.3 0.7 Other differences, net (1.0 ) 0.6 0.3 Valuation allowance 13.3 17.6 18.8 $ 12.3 $ 0.8 $ 12.4
Components of Deferred Tax Assets (Liabilities)	The tax effected deferred tax assets (liabilities) are comprised of the following components (amounts in millions): September 27, September 28, 2014 Accounts receivable, net $ 1.9 $ 1.2 Inventories 17.5 14.5 Accrued employee benefit expenses 8.4 8.8 Net operating losses 164.6 149.6 Tax credits and incentives 153.5 144.2 Accrued other expenses 9.7 11.4 Deferred equity compensation 18.9 16.7 Property and equipment, net 13.8 3.1 Other assets 11.4 11.8 Total deferred tax assets 399.7 361.3 Intangible assets (137.1 ) (127.2 ) Foreign declared dividend — (3.6 ) Total deferred tax liabilities (137.1 ) (130.8 ) Less valuation allowance (250.6 ) (218.9 ) $ 12.0 $ 11.6
Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (amounts in millions): September 27, September 28, September 29, 2013 Beginning gross unrecognized tax benefits $ 97.7 $ 69.6 $ 58.0 Additions based on tax positions related to the current year 3.5 2.4 3.2 Additions based on current year acquisitions 16.2 28.9 — Additions based on tax positions of prior years 4.8 0.4 12.9 Reductions based on tax positions of prior years — — (2.8 ) Reductions for lapses and settlements (0.4 ) (3.6 ) (1.7 ) Ending gross unrecognized tax benefit $ 121.8 $ 97.7 $ 69.6

Credit Agreement (Tables)

Credit Agreement (Tables)	12 Months Ended
	Sep. 27, 2015
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments and Interest Rates	At September 27, 2015 , the principal amounts outstanding were Eurodollar Rate loans and interest rate information as of September 27, 2015 , were as follows (amounts in millions, except percentages): Principal Outstanding Base Rate Base Rate Margin Eurodollar Rate Margin Eurodollar Floor Applicable Rate Revolving and swingline loans $ 100.0 3.25 % 1.00 % 2.00 % — % 2.15 % Term A loan $ 325.0 3.25 % 1.00 % 2.00 % — % 2.15 % Term B loan $ 573.0 3.25 % 1.50 % 2.50 % 0.75 % 3.25 %

Other Long-Term Liabilities (Ta

Other Long-Term Liabilities (Tables)	12 Months Ended
	Sep. 27, 2015
Other Liabilities Disclosure [Abstract]
Other Long-Term Liabilities	Other long-term liabilities consisted of (amounts in millions): September 27, September 28, Unrecognized tax benefits $ 19.8 $ 17.4 Deferred rent 11.2 13.7 Pension and retirement 8.9 8.9 Restructuring 3.4 3.8 Other 3.0 3.1 Total $ 46.3 $ 46.9

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Sep. 27, 2015
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 30, 2012 2.7 Granted 1.9 $ 20.39 Vested (1.4 ) Forfeited (0.1 ) 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
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 30, 2012 0.4 Granted 0.4 Vested (0.2 ) 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
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 30, 2012 7.0 $ 20.26 $ 21.6 2.5 Exercised (1.9 ) $ 14.16 $ 17.0 Forfeited (0.4 ) $ 24.33 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 Exercisable at September 27, 2015 0.6 $ 19.13 $ 7.5 3.6 Exercisable and expected to vest after September 27, 2015 0.7 $ 19.60 $ 9.1 4.0
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 September 27, 2015 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 0.4 $ 14.18 0.4 $ 14.39 Greater than $20.00 0.2 $ 27.36 0.3 $ 25.91 0.6 $ 19.13 0.7 $ 19.60
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	Weighted-average fair value and weighted-average assumptions used in the calculation of compensation expense for assumed grants in 2014 and 2015 are as follows. There were no stock options or stock appreciation rights granted or assumed in 2013. Fair Value Risk Free Rate Expected Dividend Yield Expected Life (Years) Expected Volatility September 28, 2014 $ 20.08 0.5 % — % 2.7 31.0 % September 27, 2015 $ 24.18 0.1 % — % 0.7 36.6 %

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Sep. 27, 2015
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): 2016 2017 2018 2019 2020 Thereafter $ 19.8 $ 17.1 $ 15.1 $ 13.5 $ 12.2 $ 10.6

Restructuring and Severance C37

Restructuring and Severance Charges (Tables)	12 Months Ended
	Sep. 27, 2015
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 28, 2014 $ 4.1 $ 8.2 $ — $ 12.3 Assumed from acquisition 0.1 — — 0.1 Provisions 10.6 2.6 3.9 17.1 Reversal of prior provision (0.6 ) (1.1 ) — (1.7 ) Cash expenditures (11.3 ) (5.9 ) (2.2 ) (19.5 ) Other non-cash settlement — (0.6 ) (1.6 ) (2.2 ) Balance at September 27, 2015 $ 2.9 $ 3.2 $ 0.1 $ 6.2

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Sep. 27, 2015
Segment Reporting [Abstract]
Net Sales, End Market and Long Lived Assets by Geographic Area	Net sales based on a customer's ship-to location and by estimated end market are as follows (amounts in millions): 2015 2014 2013 United States $ 610.0 $ 604.4 $ 514.6 Europe 189.8 163.7 142.3 Asia 399.7 338.4 292.6 Other 46.1 31.8 26.4 Total $ 1,245.6 $ 1,138.3 $ 975.9 Aerospace $ 191.4 $ 169.6 $ 187.0 Communications 451.7 407.6 278.1 Defense & Security 335.8 302.7 306.3 Industrial 266.7 258.4 204.5 Total $ 1,245.6 $ 1,138.3 $ 975.9 Property and equipment, net by geographic area are as follows (amounts in millions): 2015 2014 2013 United States $ 117.6 $ 117.9 $ 100.7 Europe 13.9 12.2 12.6 Asia 18.9 16.8 10.2 Other 2.3 1.8 1.7 Total $ 152.7 $ 148.7 $ 125.2

Unaudited Selected Quarterly 39

Unaudited Selected Quarterly Financial Data (Tables)	12 Months Ended
	Sep. 27, 2015
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	Selected quarterly financial data are as follows (amounts in millions, except earnings per share): Quarters ended in fiscal year 2015 September 27, June 28, March 29, December 28, Net sales $ 328.8 $ 317.1 $ 296.2 $ 303.5 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 Quarters ended in fiscal year 2014 September 28, June 29, March 30, December 29, Net sales $ 303.3 $ 292.3 $ 287.0 $ 255.7 Gross profit $ 171.0 $ 153.6 $ 148.6 $ 138.3 Net income (loss) $ 32.8 $ (4.3 ) $ (6.8 ) $ 1.4 Basic earnings (loss) per share $ 0.35 $ (0.05 ) $ (0.07 ) $ 0.02 Diluted earnings (loss) per share $ 0.34 $ (0.05 ) $ (0.07 ) $ 0.02

Description of business and s40

Description of business and summary of significant accounting policies - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Sep. 28, 2014	Jun. 29, 2014	Mar. 30, 2014	Dec. 29, 2013	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Basis of Presentation [Line Items]
Stock awards excluded from computation of diluted EPS									0.2	2.8	1.8
Net income	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ 32.8	$ (4.3)	$ (6.8)	$ 1.4	$ 84.6	$ 23.1	$ 43.7
Debt Issuance Cost									$ 11.7	$ 4.7
International
Basis of Presentation [Line Items]
Percentage of net sales from international market									51.00%		47.00%
Defense And Security
Basis of Presentation [Line Items]
Concentration of credit risk in major customer									27.00%
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									2,014
Foreign Country | Minimum
Basis of Presentation [Line Items]
Open tax years by major tax jurisdiction									2,011
Foreign Country | Maximum
Basis of Presentation [Line Items]
Open tax years by major tax jurisdiction									2,014

Description of business and s41

Description of business and summary of significant accounting policies - Fair Value Measurements Using (Detail) - USD ($) $ in Millions	Sep. 27, 2015	Sep. 28, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liabilities		$ 0.1
Fair Value, Inputs, Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liabilities		0
Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liabilities		0.1
Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liabilities		0
Measured on a recurring basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	$ 1.7	4.1
Measured on a recurring basis | Fair Value, Inputs, Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	1.7	4.1
Measured on a recurring basis | Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	0	0
Measured on a recurring basis | Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities, Current	$ 0	$ 0

Description of business and s42

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
	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Sep. 28, 2014	Jun. 29, 2014	Mar. 30, 2014	Dec. 29, 2013	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
BASIC
Net income (loss)	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ 32.8	$ (4.3)	$ (6.8)	$ 1.4	$ 84.6	$ 23.1	$ 43.7
Weighted-average common shares outstanding									94.2	92.9	89.5
Basic earnings (loss) per share	$ 0.27	$ 0.16	$ 0.26	$ 0.21	$ 0.35	$ (0.05)	$ (0.07)	$ 0.02	$ 0.90	$ 0.25	$ 0.49
DILUTED
Net income (loss)	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ 32.8	$ (4.3)	$ (6.8)	$ 1.4	$ 84.6	$ 23.1	$ 43.7
Weighted-average common shares outstanding									94.2	92.9	89.5
Dilutive effect of stock awards									1.7	1.6	1.8
Weighted-average common shares outstanding on a diluted basis									95.9	94.5	91.3
Diluted earnings (loss) per share	$ 0.26	$ 0.15	$ 0.26	$ 0.21	$ 0.34	$ (0.05)	$ (0.07)	$ 0.02	$ 0.88	$ 0.24	$ 0.48

Acquisitions (Detail)

Acquisitions (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended									9 Months Ended	12 Months Ended
	Nov. 30, 2013	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Sep. 28, 2014	Sep. 28, 2014	Jun. 29, 2014	Mar. 30, 2014	Dec. 29, 2013	Jun. 30, 2013	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Business Acquisition [Line Items]
Goodwill		$ 1,139.3				$ 885.6	$ 885.6					$ 1,139.3	$ 885.6	$ 790.2
Net sales		$ 328.8	$ 317.1	$ 296.2	$ 303.5		$ 303.3	$ 292.3	$ 287	$ 255.7		1,245.6	$ 1,138.3	$ 975.9
Vitesse
Business Acquisition [Line Items]
Cash consideration	$ 383.2
Cash and cash equivalents	16.2
Accounts receivable	9.4
Inventories	33.8
Other current assets	4.7
Property and equipment	2.4
Deferred income taxes, net	5.6
Other assets	2.3
Identifiable intangible assets	102.4
Goodwill	252.5
Current liabilities	(28.1)
Long term debt	(17.7)
Other non-current liabilities	(0.3)
Gross contractual amount of acquired receivables	10
Asset Amount	102.4
Net sales												0
Business Acquisition, Pro Forma Information [Abstract]
Net sales											$ 1,289	1,294.8
Net income (loss)											$ (26.2)	$ 71.8
Basic (usd per share)											$ (0.28)	$ 0.76
Diluted (usd per share)											$ (0.28)	$ 0.75
Symmetricom [Member]
Business Acquisition [Line Items]
Cash consideration	312.7
Mingoa and Centellax [Member]
Business Acquisition [Line Items]
Cash consideration						$ 51.5
Completed technology | Vitesse
Business Acquisition [Line Items]
Identifiable intangible assets	87
Asset Amount	$ 87
Useful life of intangible asset	7 years
Customer relationships | Vitesse
Business Acquisition [Line Items]
Identifiable intangible assets	$ 14.4
Asset Amount	$ 14.4
Useful life of intangible asset	9 years
Other | Vitesse
Business Acquisition [Line Items]
Identifiable intangible assets	$ 1
Asset Amount	$ 1
Useful life of intangible asset	1 year

Inventories (Detail)

Inventories (Detail) - USD ($) $ in Millions	3 Months Ended
	Jun. 28, 2015	Sep. 27, 2015	Sep. 28, 2014
Inventory Disclosure [Abstract]
Inventory Write-down	$ 7.9
Raw materials		$ 56.5	$ 55.3
Work in progress		111.7	94
Finished goods		59	55.7
Total		$ 227.2	$ 205

Property and Equipment (Detail)

Property and Equipment (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 536	$ 436.8
Accumulated depreciation	(393.8)	(303.8)
Land	1.9	2.1
Construction in progress	8.6	13.6
Property and equipment, net	$ 152.7	148.7	$ 125.2
Property plant and equipment useful life	Shorter of asset life or life of lease
Depreciation expense	$ 36.2	32.9	$ 28.8
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	43	40.1
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	429.1	339.8
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	9.8	9.9
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 54.1	$ 47
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 Asset46

Goodwill and Intangible Assets, Net - Goodwill and Intangible Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	$ 824.7	$ 722.4
Accumulated Amortization	(466.9)	(370.5)
Goodwill	1,139.3	885.6	$ 790.2
Completed technology
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	489.7	402.7
Accumulated Amortization	(251.7)	(201.3)
Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	316.2	301.8
Accumulated Amortization	(197.1)	(152.5)
Backlog, trade name and other
Goodwill and Intangible Assets Disclosure [Line Items]
Gross Carrying Value	18.8	17.9
Accumulated Amortization	$ (18.1)	$ (16.7)
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

Goodwill and Intangible Asset47

Goodwill and Intangible Assets, Net - Reconciliation of Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Beginning balance	$ 885.6	$ 790.2
Additions from acquisitions	253.7	95.4
Ending balance	$ 1,139.3	$ 885.6

Goodwill and Intangible Asset48

Goodwill and Intangible Assets, Net - Amortization of Intangible Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	$ 96.5	$ 92.8	$ 84.8
Completed technology
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	50.4	43.9	39
Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	44.6	45	42.6
Backlog, trade name and other
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization of intangible assets	$ 1.5	$ 3.9	$ 3.2

Goodwill and Intangible Asset49

Goodwill and Intangible Assets, Net - Estimated Amortization Expense (Detail) $ in Millions	Sep. 27, 2015USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,016	$ 100.8
2,017	96.6
2,018	53.2
2,019	30.8
2,020	25.6
Thereafter	$ 50.8

Accrued Liabilities (Detail)

Accrued Liabilities (Detail) - USD ($) $ in Millions	Sep. 27, 2015	Sep. 28, 2014
Accounts Payable and Accrued Liabilities, Current [Abstract]
Payroll, bonus, and employee benefits	$ 33.3	$ 34.3
Deferred revenue	9.7	11.4
Outside services	9.2	9.6
Warranties	6.4	6.9
Commissions	3.8	4
Licenses	6	1.1
Accrued Rent, Current	2.6	0.7
Restructuring and severance	2.5	8.4
Customer Deposits, Current	2.2	1.1
Property and sales tax	1.3	1.1
Income taxes	1.4	1
Other	8.4	6.1
Total	$ 86.8	$ 85.7

Income Taxes - Pretax Income (L

Income Taxes - Pretax Income (Loss) (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Disclosure - Pretax Income (Loss) [Abstract]
Domestic	$ (14.9)	$ (62.7)	$ (38.7)
Foreign	111.8	86.6	94.8
Income (loss) before income taxes	$ 96.9	$ 23.9	$ 56.1

Income Taxes - Provision for In

Income Taxes - Provision for Income Taxes (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Income Tax Disclosure [Abstract]
Federal	$ 0	$ 0	$ 0.8
State	0.2	0.3	0.8
Foreign	4.2	3.9	3.1
Federal	4.6	(6.5)	2.3
State	0	(0.2)	1.4
Foreign	3.3	3.3	4
Income Tax Expense (Benefit)	$ 12.3	$ 0.8	$ 12.4

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Income Taxes [Line Items]
Income Tax Expense (Benefit)	$ 12.3	$ 0.8	$ 12.4
Income (loss) before income taxes	96.9	23.9	56.1
Increase in valuation allowance	(31.6)	8.9
Excess tax benefit from employee stock compensation	51.6
Estimated increase in equity from excess tax benefit	51.6
Tax credits that carryforward indefinitely	8.9
Undistributed earnings of foreign operations	471.2	430.4
Unrecognized tax benefit, interest and penalties	0.7	0.7	$ 0.1
Unrecognized tax benefit, cumulative interest and penalties	7.4	$ 6.6
Unrecognized tax benefit that would impact effective tax rate	62.5
within the next twelve months
Income Taxes [Line Items]
Anticipated decrease in unrecognized tax benefits	28.3
Internal Revenue Service (IRS)
Income Taxes [Line Items]
Net operating losses carryforward, subject to expiration	366.4
Research and experimentation credits	52.3
Federal foreign tax credits	4.7
State and Local Jurisdiction
Income Taxes [Line Items]
Net operating losses carryforward, subject to expiration	253.1
Research and experimentation credits	91.9
Foreign Country
Income Taxes [Line Items]
Net operating losses carryforward, not subject to expiration	283.7
Research and experimentation credits	81.9
Tax credit related to incentive deductions	$ 16.2
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	2,011
Maximum | Internal Revenue Service (IRS)
Income Taxes [Line Items]
Open tax years by major tax jurisdiction	2,014
Maximum | Foreign Country
Income Taxes [Line Items]
Open tax years by major tax jurisdiction	2,014

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
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Income Tax Disclosure [Abstract]
Tax computed at federal statutory rate	$ 33.9	$ 8.4	$ 19.6
State taxes, net of federal impact	(2.1)	(1.1)	(1.6)
Foreign income taxed at different rates	(33.1)	(24.7)	(20.5)
Tax credits	(5.1)	(2.8)	(5.4)
Stock award compensation	1.3	1.2	0.2
Unrecognized tax benefits	3.7	1.4	(0.4)
U.S. tax on foreign income	1.3	4.1	1.4
Income tax return to provision	0	(0.2)	(0.9)
Non-deductible permanent items	0.9	0.9	0.2
Pre-acquisition loss carryforwards	0	(11.4)	0
Effective Income Tax Reconciliation, Prior Year Adjustments On Deferred Taxes	0	2.9	0
Effective Income Tax Reconciliation, Deduction, Foreign Declared Dividends, Amount	(0.5)	3.6	0
Withholding taxes	(0.3)	0.3	0.7
Other differences, net	(1)	0.6	0.3
Valuation allowance	13.3	17.6	18.8
Income Tax Expense (Benefit)	$ 12.3	$ 0.8	$ 12.4

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Income Tax Disclosure [Abstract]
Accounts receivable, net	$ 1.9	$ 1.2
Inventories	17.5	14.5
Accrued employee benefit expenses	8.4	8.8
Net operating losses	164.6	149.6
Tax credits	153.5	144.2
Accrued other expenses	9.7	11.4
Deferred equity compensation	18.9	16.7
Property and equipment, net	(13.8)	(3.1)
Other assets	11.4	11.8
Total deferred tax assets	399.7	361.3
Intangible assets	(137.1)	(127.2)
Deferred Tax Liabilities, Foreign Declared Dividend	0	(3.6)
Effective Income Tax Reconciliation, Deduction, Foreign Declared Dividends, Amount	(0.5)	3.6	$ 0
Total deferred tax liabilities	(137.1)	(130.8)
Less valuation allowance	(250.6)	(218.9)
Deferred Tax Assets (Liabilities), Net, Total	$ 12	$ 11.6

Income Taxes - Reconciliation56

Income Taxes - Reconciliation of the Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning gross unrecognized tax benefits	$ 97.7	$ 69.6	$ 58
Additions based on tax positions related to the current year	3.5	2.4	3.2
Additions based on current year acquisitions	16.2	28.9	0
Additions based on tax positions of prior years	4.8	0.4	12.9
Unrecognized Tax Benefits, Decreases Resulting from Prior Period Tax Positions	0	0	(2.8)
Reductions for lapses and settlements	(0.4)	(3.6)	(1.7)
Ending gross unrecognized tax benefit	$ 121.8	$ 97.7	$ 69.6

Credit Agreement (Detail)

Credit Agreement (Detail) $ in Millions	Apr. 28, 2015USD ($)	Apr. 15, 2015USD ($)	Sep. 27, 2015USD ($)	Sep. 28, 2014USD ($)	Mar. 31, 2015USD ($)
Line of Credit Facility [Line Items]
Debt Issuance Cost			$ 11.7	$ 4.7
Interest Rate Swap
Line of Credit Facility [Line Items]
Derivative Instruments, Gain Recognized in Income			(0.6)	(1.3)
Derivative, Gain on Derivative			0.6	1.3
Revolving Credit Facility
Line of Credit Facility [Line Items]
Borrowed under term loan facility	$ 100
Incremental Term Loan Facility
Line of Credit Facility [Line Items]
Borrowed under term loan facility	325		573
Line of Credit Facility, Maximum Borrowing Capacity	$ 325				$ 325
Debt Instrument, Periodic Payment, Principal		$ 8.1
Loans payable
Line of Credit Facility [Line Items]
Fair value outstanding term loan			$ 995.9	$ 693
Minimum
Line of Credit Facility [Line Items]
Excess Cash Flow Percentage			0.00%
Consolidated Leverage Ratio			1
Maximum
Line of Credit Facility [Line Items]
Excess Cash Flow Percentage			50.00%
Consolidated Leverage Ratio			3
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 225
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			3.25%
Basis spread on variable rate			1.00%
Base Rate | Term Loan | Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			3.25%
Base Rate | Incremental Term Loan Facility | Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			3.25%
Basis spread on variable rate	1.00%		1.50%
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			2.00%
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	2.00%		2.50%
Applicable Rate | Revolving Loans And Swingline [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate During Period			2.15%
Applicable Rate | Term Loan
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate During Period			2.15%
Applicable Rate | Incremental Term Loan Facility
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate During Period			3.25%

Other Long-Term Liabilities (De

Other Long-Term Liabilities (Detail) - USD ($) $ in Millions	Sep. 27, 2015	Sep. 28, 2014
Other Liabilities Disclosure [Abstract]
Unrecognized tax benefits	$ 19.8	$ 17.4
Deferred rent	11.2	13.7
Pension and retirement	8.9	8.9
Restructuring	3.4	3.8
Other	3	3.1
Total	$ 46.3	$ 46.9

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Detail) shares in Millions, $ in Millions	12 Months Ended
	Sep. 27, 2015USD ($)shares	Sep. 28, 2014USD ($)shares	Sep. 29, 2013USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $	$ 49.8	$ 43.9	$ 35.2
Unamortized compensation expense related to unvested options and restricted stock awards, net of forfeitures | $	$ 56.3
Compensation expense related to nonvested restricted stock options, recognition periods	1 year 5 months
Common stock for delivery under awards that have been and may be granted	11.7	14.1	12.2
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
Shares limit in common stock	33.3
Plan expiration date	Dec. 5, 2021
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-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Awards Activity and Price (Detail) - Restricted Stock Award - $ / shares shares in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Restricted Stock Awards
Outstanding and Nonvested, Balance	3.1	3.1	2.7
Assumed from acquisition	0.3
Granted	1.3	1.6	1.9
Vested	(1.5)	(1.4)	(1.4)
Canceled	(0.2)	(0.2)	(0.1)
Outstanding and Nonvested, Balance	3	3.1	3.1
Weighted- Average Grant Price
Granted	$ 29.37	$ 24.67	$ 20.39
Assumed from acquisition	$ 33.01

Stock-Based Compensation - Perf

Stock-Based Compensation - Performance Shares (Details) - Performance stock units - shares shares in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 30, 2012	Jun. 29, 2014	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage relative to net sales	25.00%		70.00%	40.00%
Vesting percentage relative to earnings per share	75.00%		30.00%	60.00%
Performance Based Compensation, Shares Awarded as a Percentage of Grants, Peer Group Based		125.00%	150.00%		125.00%
Performance Based Compensation Percentage			225.00%	200.00%
Performance Units
Outstanding and Nonvested, Balance	0.4	0.6	0.7	0.6	0.4
Granted			0.3	0.4	0.4
Vested			(0.3)	(0.3)	(0.2)
Outstanding and Nonvested, Balance			0.7	0.7	0.6

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
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013	Sep. 30, 2012
Stock Options
Outstanding Beginning Balance	2.7	4.7	7
Assumed from acquisition	0.2	0.6
Exercised	(2.1)	(1.2)	(1.9)
Forfeited	(0.1)	(1.4)	(0.4)
Outstanding Ending Balance	0.7	2.7	4.7	7
Exercisable stock options	0.6
Exercisable and expected to vest stock options	0.7
Weighted average Exercise Price
Outstanding Beginning Balance	$ 22.70	$ 22.49	$ 20.26
Assumed from acquisition	24.18	20.08
Exercised	23.83	16.39	14.16
Forfeited	23.90	26.55	24.33
Outstanding Ending Balance	19.60	$ 22.70	$ 22.49	$ 20.26
Exercisable stock options, Weighted Average Exercise Price	19.13
Exercisable and expected to vest stock options, Weighted Average Exercise Price	$ 19.60
Intrinsic Value
Outstanding, Intrinsic Value	$ 9.1	$ 7.4	$ 14.7	$ 21.6
Exercised, Intrinsic Value	15.8	$ 17	$ 17
Exercisable stock options, Intrinsic Value	7.5
Exercisable and expected to vest stock options, Intrinsic Value	$ 9.1
Weighted Average Remaining Life
Outstanding, Weighted Average Remaining Life	4 years	2 years	1 year 7 months 31 days	2 years 6 months
Exercisable stock options, Weighted Average Remaining Life	3 years 6 months 30 days
Exercisable and expected to vest stock options, Weighted Average Remaining Life	4 years

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	Sep. 27, 2015$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable stock options, Quantity | shares	0.6
Exercisable stock options, Weighted Average Exercise Price	$ 19.13
Outstanding stock options, Quantity | shares	0.7
Outstanding stock options, Weighted Average Exercise Price	$ 19.60
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	0.4
Exercisable stock options, Weighted Average Exercise Price	$ 14.18
Outstanding stock options, Quantity | shares	0.4
Outstanding stock options, Weighted Average Exercise Price	$ 14.39
Greater than $20.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable stock options, Quantity | shares	0.2
Exercisable stock options, Weighted Average Exercise Price	$ 27.36
Outstanding stock options, Quantity | shares	0.3
Outstanding stock options, Weighted Average Exercise Price	$ 25.91

Stock-Based Compensation - Awar

Stock-Based Compensation - Awards Granted, Weighted-Average Exercise Price, Weighted-Average Fair Value and Weighted-Average Assumptions Used in the Calculation of Compensation Expense (Detail) - Employee Stock Option And Stock Appreciation Rights - $ / shares	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per award	$ 24.18	$ 20.08
Risk free rate	0.10%	0.50%
Expected dividend yield	0.00%	0.00%
Expected life	8 months	2 years 8 months 6 days
Expected volatility	36.60%	31.00%

Employee Benefit Plans (Details

Employee Benefit Plans (Details)	12 Months Ended
	Sep. 27, 2015USD ($)Year	Sep. 28, 2014USD ($)	Sep. 29, 2013USD ($)
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	$ 3,700,000
Fair value of plan assets	4,300,000
Benefit obligations	(6,700,000)
Unrealized actuarial loss on pension benefits	(300,000)	$ (700,000)	$ (200,000)
Assumptions used calculating benefit obligation, discount rate		2.10%	3.20%
Estimated future employer contributions in the next twelve months	$ 0

Stock Repurchase Program (Detai

Stock Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions	12 Months Ended
	Sep. 27, 2015	Jul. 21, 2015	Sep. 09, 2014
Equity [Abstract]
Stock repurchase program, authorized amount		$ 100,000,000	$ 100,000,000
Repurchase of outstanding common stock (in shares)	2.7
Repurchase of outstanding common stock	$ 75,000,000
Stock repurchased during period, average cost per share	$ 28.03
Stock repurchase program, remaining authorized repurchase amount	$ 125,000,000

Commitments and Contingencies -

Commitments and Contingencies - Aggregate Undiscounted Future Minimum Rental Payments (Detail) $ in Millions	Sep. 27, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 19.8
2,017	17.1
2,018	15.1
2,019	13.5
2,020	12.2
Thereafter	$ 10.6

Commitments and Contingencies68

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 1998	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Commitments and Contingencies Disclosure [Abstract]
Lease expense		$ 21.5	$ 23.5	$ 20.2
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		$ 2.3	$ 1.9
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 C69

Restructuring and Severance Charges - Additional Information (Detail) Person in Thousands, $ in Millions	12 Months Ended
	Sep. 27, 2015USD ($)Person	Sep. 28, 2014USD ($)	Sep. 29, 2013USD ($)
Schedule of Status of Facilities by Location [Line Items]
Recorded severance accruals	$ 3.4	$ 3.8
Restructuring and severance charges	15.4	31.5	$ 9.9
Employee Severance
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Reversal of Prior Provision	10
Restructuring, Settlement and Impairment Provisions	$ 10.6
Number of employees | Person	250
Contract Termination Costs
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Settlement and Impairment Provisions	$ 2.6
Restructuring Reserve, Accrual Adjustment	(1.1)
Other Associated Costs
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Settlement and Impairment Provisions	3.9
Other Facilities
Schedule of Status of Facilities by Location [Line Items]
Restructuring, Settlement and Impairment Provisions	17.1
Restructuring Reserve, Accrual Adjustment	(1.7)
Payments for Restructuring	19.5
Restructuring Reserve, Settled without Cash	2.2
Recorded severance accruals	6.2	12.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restructuring Liabilities	0.1
Other Facilities | Employee Severance
Schedule of Status of Facilities by Location [Line Items]
Restructuring Reserve, Accrual Adjustment	(0.6)
Payments for Restructuring	11.3
Restructuring Reserve, Settled without Cash	0
Recorded severance accruals	2.9	4.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restructuring Liabilities	0.1
Other Facilities | Contract Termination Costs
Schedule of Status of Facilities by Location [Line Items]
Payments for Restructuring	5.9
Restructuring Reserve, Settled without Cash	0.6
Recorded severance accruals	3.2	8.2
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
Payments for Restructuring	2.2
Restructuring Reserve, Settled without Cash	1.6
Recorded severance accruals	0.1	$ 0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restructuring Liabilities	0
Vitesse | Employee Severance
Schedule of Status of Facilities by Location [Line Items]
Restructuring and severance charges	$ 2.9

Restructuring and Severance C70

Restructuring and Severance Charges - Restructuring Activities and Accrued Liabilities in the Consolidated Balance Sheets (Detail) $ in Millions	12 Months Ended
	Sep. 27, 2015USD ($)
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 3.8
Ending Balance	3.4
Employee Severance
Restructuring Cost and Reserve [Line Items]
Provisions	(10.6)
Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Provisions	(2.6)
Other Associated Costs
Restructuring Cost and Reserve [Line Items]
Provisions	(3.9)
Other Facilities
Restructuring Cost and Reserve [Line Items]
Beginning Balance	12.3
Provisions	(17.1)
Cash expenditures	(19.5)
Other non-cash settlement	(2.2)
Ending Balance	6.2
Other Facilities | Employee Severance
Restructuring Cost and Reserve [Line Items]
Beginning Balance	4.1
Cash expenditures	(11.3)
Other non-cash settlement	0
Ending Balance	2.9
Other Facilities | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Beginning Balance	8.2
Cash expenditures	(5.9)
Other non-cash settlement	(0.6)
Ending Balance	3.2
Other Facilities | Other Associated Costs
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Cash expenditures	(2.2)
Other non-cash settlement	(1.6)
Ending Balance	$ 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
	Sep. 27, 2015USD ($)	Jun. 28, 2015USD ($)	Mar. 29, 2015USD ($)	Dec. 28, 2014USD ($)	Sep. 28, 2014USD ($)	Jun. 29, 2014USD ($)	Mar. 30, 2014USD ($)	Dec. 29, 2013USD ($)	Sep. 27, 2015USD ($)segment	Sep. 28, 2014USD ($)	Sep. 29, 2013USD ($)
Segment Reporting Disclosure [Line Items]
Number of Reportable Segments | segment									1
Net Sales	$ 328.8	$ 317.1	$ 296.2	$ 303.5	$ 303.3	$ 292.3	$ 287	$ 255.7	$ 1,245.6	$ 1,138.3	$ 975.9
Aerospace
Segment Reporting Disclosure [Line Items]
Net Sales									191.4	169.6	187
Communication
Segment Reporting Disclosure [Line Items]
Net Sales									$ 451.7	407.6	278.1
Defense And Security
Segment Reporting Disclosure [Line Items]
Concentration of credit risk in major customer									27.00%
Net Sales									$ 335.8	302.7	306.3
Industrial
Segment Reporting Disclosure [Line Items]
Net Sales									266.7	258.4	204.5
United States
Segment Reporting Disclosure [Line Items]
Net Sales									610	604.4	514.6
Europe
Segment Reporting Disclosure [Line Items]
Net Sales									$ 189.8	$ 163.7	$ 142.3
Asia
Segment Reporting Disclosure [Line Items]
Concentration of credit risk in major customer									12.00%	0.00%	0.00%
Net Sales									$ 399.7	$ 338.4	$ 292.6
Other Geographical [Member]
Segment Reporting Disclosure [Line Items]
Net Sales									$ 46.1	$ 31.8	$ 26.4

Segment Information - Long Live

Segment Information - Long Lived Assets by Geographic Area (Detail) - USD ($) $ in Millions	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 152.7	$ 148.7	$ 125.2
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	117.6	117.9	100.7
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	13.9	12.2	12.6
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	18.9	16.8	10.2
Other Geographic Area [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 2.3	$ 1.8	$ 1.7

Unaudited Selected Quarterly 73

Unaudited Selected Quarterly Financial Data - Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Sep. 28, 2014	Jun. 29, 2014	Mar. 30, 2014	Dec. 29, 2013	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Quarterly Financial Information Disclosure [Abstract]
Net Sales	$ 328.8	$ 317.1	$ 296.2	$ 303.5	$ 303.3	$ 292.3	$ 287	$ 255.7	$ 1,245.6	$ 1,138.3	$ 975.9
Gross profit	174.8	172.1	169.3	168.1	171	153.6	148.6	138.3	684.3	611.5	557.2
Net income (loss)	$ 25.3	$ 14.7	$ 24.9	$ 19.7	$ 32.8	$ (4.3)	$ (6.8)	$ 1.4	$ 84.6	$ 23.1	$ 43.7
Basic earnings (loss) per share	$ 0.27	$ 0.16	$ 0.26	$ 0.21	$ 0.35	$ (0.05)	$ (0.07)	$ 0.02	$ 0.90	$ 0.25	$ 0.49
Diluted earnings (loss) per share	$ 0.26	$ 0.15	$ 0.26	$ 0.21	$ 0.34	$ (0.05)	$ (0.07)	$ 0.02	$ 0.88	$ 0.24	$ 0.48

Subsequent Event (Details)

Subsequent Event (Details) - Subsequent event $ / shares in Units, $ in Billions	Oct. 30, 2015USD ($)$ / shares
Subsequent Event [Line Items]
Proposed consideration in acquisition, cash dividend per share | $ / shares	$ 9.04
Proposed consideration in acquisition, multiple per share	0.0771
Proposed acquisition, implied enterprise value of acquiree	$ 2.3

VALUATION AND QUALIFYING ACCO75

VALUATION AND QUALIFYING ACCOUNTS (Detail) - Tax Valuation Allowance - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 218.9	$ 210.1	$ 196.1
Charged to costs and expenses	13.3	17.6	18.8
Charged to other accounts	18.4	(8.8)	(4.8)
Deductions- recoveries and write-offs	0	0	0
Balance at end of period	$ 250.6	$ 218.9	$ 210.1