Document And Entity Information	3 Months Ended	6 Months Ended
Document And Entity Information	Mar. 30, 2012	Mar. 30, 2012	Apr. 27, 2012
Document And Entity Information
Entity Registrant Name	Skyworks Solutions, Inc.
Entity Central Index Key	0000004127
Document Type	10-Q
Document Period End Date		Mar. 30, 2012
Amendment Flag	false
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--09-28
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding			189,651,416

Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 30, 2012	Apr. 01, 2011	Mar. 30, 2012	Apr. 01, 2011
Net revenue	$ 364,690	$ 325,411	$ 758,430	$ 660,531
Cost of goods sold	212,418	184,430	434,308	371,012
Gross profit	152,272	140,981	324,122	289,519
Operating expenses:
Research and development	52,986	39,618	99,927	78,161
Selling, general and administrative	38,270	31,462	73,972	62,068
Arbitration costs	1,967	203	9,174	648
Amortization of intangibles	9,340	1,638	15,652	3,240
Restructuring Charges	5,895	0	6,615	0
Total operating expenses	108,458	72,921	205,340	144,117
Operating income	43,814	68,060	118,782	145,402
Interest expense	(107)	(461)	(588)	(998)
Gain on early retirement of convertible debt	63	0	139	0
Other loss, net	(310)	(114)	(211)	(183)
Income before income taxes	43,460	67,485	118,122	144,221
Provision for income taxes	9,427	17,525	26,963	33,393
Net income	$ 34,033	$ 49,960	$ 91,159	$ 110,828
Earnings per share:
Basic (in dollars per share)	$ 0.18	$ 0.27	$ 0.49	$ 0.61
Diluted (in dollars per share)	$ 0.18	$ 0.26	$ 0.48	$ 0.58
Weighted average shares:
Basic (in shares)	185,206	183,471	184,581	182,088
Diluted (in shares)	191,016	191,961	190,348	190,251

Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 30, 2012	Sep. 30, 2011
Current assets:
Cash and cash equivalents	$ 306,474	$ 410,087
Restricted cash	862	712
Receivables, net of allowance for doubtful accounts of $1,272 and $785, respectively	211,488	177,940
Inventory	196,558	198,183
Other current assets	36,950	29,412
Total current assets	752,332	816,334
Property, plant and equipment, net	252,312	251,365
Goodwill	802,817	663,041
Intangible assets, net	111,103	86,808
Deferred tax assets, net	75,595	60,863
Other assets	13,167	11,978
Total assets	2,007,326	1,890,389
Current liabilities:
Short-term debt	0	26,089
Accounts payable	136,677	115,290
Accrued compensation and benefits	31,350	35,684
Other current liabilities	74,615	70,033
Total current liabilities	242,642	247,096
Other long-term liabilities	44,440	34,198
Total liabilities	287,082	281,294
Commitments and contingencies
Stockholders' equity:
Preferred stock, no par value: 25,000 shares authorized, no shares issued
Common stock, $0.25 par value: 525,000 shares authorized; 200,061 shares issued and 189,527 shares outstanding at March 30, 2012 and 195,407 shares issued and 186,386 shares outstanding at September 20, 2011	47,382	46,597
Additional paid-in capital	1,843,083	1,795,958
Treasury stock, at cost	(158,769)	(130,854)
Accumulated deficit	(10,116)	(101,275)
Accumulated other comprehensive loss	(1,336)	(1,331)
Total stockholders' equity	1,720,244	1,609,095
Total liabilities and stockholders' equity	$ 2,007,326	$ 1,890,389

Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 30, 2012	Sep. 30, 2011
Current assets:
Allowance for doubtful accounts	$ 1,272	$ 785
Stockholders' Equity:
Preferred stock, par value
Preferred stock, shares authorized	25,000	25,000
Preferred stock, shares issued
Common stock, par value	$ 0.25	$ 0.25
Common stock, shares authorized	525,000	525,000
Common stock, shares issued	200,061	195,407
Common stock, shares outstanding	189,527	186,386

Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Mar. 30, 2012	Apr. 01, 2011
Cash flows from operating activities:
Net income	$ 91,159	$ 110,828
Adjustments to reconcile net income to net cash provided by operating activities:
Share-based compensation	35,085	28,145
Depreciation	34,960	27,882
Amortization of intangible assets and other	16,117	3,945
Contribution of common shares to savings and retirement plans	7,958	6,638
Other	455	28
Deferred income taxes	(2,218)	(5,205)
Excess tax benefit from share-based payments	(5,363)	(10,887)
Changes in assets and liabilities net of acquired balances:
Receivables, net	(23,816)	(8,120)
Inventory	16,714	(25,308)
Other current and long-term assets	(4,430)	2,986
Accounts payable	11,338	(18)
Other current and long-term liabilities	11,793	15,721
Net cash provided by operating activities	194,188	157,045
Cash flows from investing activities:
Capital expenditures	(32,197)	(65,280)
Payments for acquisitions, net of cash acquired	(229,628)	(4,456)
Sales and maturities of short term investments	20,900	0
Net cash used in investing activities	(240,925)	(69,736)
Cash flows from financing activities:
Retirement of debt and line of credit	48,047	50,000
Excess tax benefit from share-based payments	5,363	10,887
Change in restricted cash	(150)	5,466
Repurchase of common stock - payroll tax withholdings on equity awards	(15,510)	(18,780)
Repurchase of common stock - share repurchase program	(12,405)	(41,564)
Net proceeds from exercise of stock options	13,873	57,226
Net cash used in financing activities	(56,876)	(36,765)
Net (decrease) increase in cash and cash equivalents	(103,613)	50,544
Cash and cash equivalents at beginning of period	410,087	453,257
Cash and cash equivalents at end of period	306,474	503,801
Supplemental cash flow disclosures:
Income taxes paid	9,115	9,844
Interest paid	$ 157	$ 263

Description Of Business And Basis Of Presentation	6 Months Ended
Description Of Business And Basis Of Presentation	Mar. 30, 2012
Organization, Consolidation and Presentation of Financial Statements [Abstract]
DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION	DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION Skyworks Solutions, Inc. together with its consolidated subsidiaries, (“Skyworks” or the “Company”) is an innovator of high reliability analog and mixed signal semiconductors. Leveraging core technologies, Skyworks offers high performance analog products supporting automotive, broadband, cellular infrastructure, energy management, industrial, medical, military, networking, smartphone and tablet applications. The Company's portfolio includes amplifiers, attenuators, circulators, detectors, diodes, directional couplers, front-end modules, hybrids, infrastructure RF subsystems, isolators, lighting and display solutions, mixers/demodulators, optocouplers, optoisolators, phase shifters, PLLs/synthesizers/VCOs, power dividers/combiners, power management devices, receivers, switches and technical ceramics. The accompanying unaudited interim consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial reporting. Certain information and footnote disclosures, normally included in annual consolidated financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”), have been condensed or omitted pursuant to those rules and regulations. However, in management's opinion, the financial information reflects all adjustments, including those of a normal recurring nature necessary to present fairly the financial position, results of operations, and cash flows of the Company for the periods presented. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the full year. This information should be read in conjunction with the Company's financial statements and notes thereto contained in the Company's Annual Report on Form 10-K for the fiscal year ended September 30, 2011, filed with the SEC on November 28, 2011 (the "2011 10-K"), as amended by Amendment No. 1 to the 2011 10-K, filed with the SEC on January 30, 2012. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, costs, expenses and accumulated other comprehensive loss that are reported in these unaudited consolidated financial statements and accompanying disclosures. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment. Significant judgment is required in determining the recognition and/or disclosure of reserves for and fair value of items such as inventory, income taxes, share-based compensation, loss contingencies, subsequent events, bad debt allowances, contingent consideration, intangible assets associated with business combinations, and overall fair value assessments of assets and liabilities, particularly those classified as level 2 or level 3 in the fair value hierarchy. In addition, significant judgment is required in determining whether a potential indicator of impairment of long-lived assets exists and in estimating future cash flows for any necessary impairment tests. Management's estimates could differ significantly from actual results. The Company has evaluated subsequent events through the date of issuance of these unaudited consolidated financial statements. The Company's fiscal year ends each year on the Friday closest to September 30. Fiscal 2012 consists of 52 weeks and ends on September 28, 2012. Fiscal 2011 consisted of 52 weeks and ended on September 30, 2011. The second quarters of fiscal 2012 and fiscal 2011 each consisted of 13 weeks and ended on March 30, 2012 and April 1, 2011, respectively.

Business Combinations

6 Months Ended

Mar. 30, 2012

Business Combinations [Abstract]

BUSINESS COMBINATIONS

On January 9, 2012, the Company acquired Advanced Analogic Technologies, Incorporated ("AATI"). The Company acquired all of the outstanding shares of AATI in exchange for an aggregated purchase price of $277.3 million, substantially comprised of cash consideration. AATI is an analog semiconductor company focused on enabling energy-efficient power management devices for consumer electronics, computing and communications markets. The acquisition expands the Company's portfolio across new vertical markets with highly complementary analog semiconductor products including battery chargers, DC/DC converters, voltage regulators and LED drivers.

The allocation of the purchase price to the assets and liabilities recognized in the Company’s acquisition of AATI was not finalized at the time of filing this quarterly report on Form 10-Q due to the proximity of the acquisition date of January 9, 2012 to the end of the Company's second fiscal quarter, March 30, 2012. The Company has, however, completed a preliminary purchase price allocation reflected in the accompanying financial statements. The preliminary allocation of the purchase price was based upon estimates and assumptions which are subject to change within the measurement period (up to one year from the acquisition date). The preliminary allocation of the purchase price is based on the estimated fair values of the assets acquired and liabilities assumed by major class related to the AATI acquisition and are reflected, as of the acquisition date, in the accompanying financial statements as follows (in thousands):



	As of
Estimated fair value of assets acquired	January 9, 2012
Cash	$	42,605
Short-term investments	20,900
Accounts receivable, net	10,712
Inventory	15,470
Deferred tax assets	18,358
Property, plant and equipment, net	3,888
Other assets	2,139
Identifiable intangible assets	40,240
Goodwill	138,796
Total assets acquired	293,108
Liabilities assumed	(15,764		)
Estimated fair value of assets acquired	$	277,344

The preliminary amount of purchase price allocated to goodwill of $138.8 million represents the synergistic value anticipated from cost efficiencies and cross-selling opportunities. The company expects that substantially all of the goodwill recognized as a result of the AATI acquisition will not be deductible for tax purposes.

The preliminary amount of the purchase price allocated to identifiable intangible assets recognized in the acquisition of AATI and the respective useful lives as of January 9, 2012 were as follows (in thousands):



	Fair Value		Weighted Average Amortization Period Remaining (in Years)
Customer relationships	$	21,200	4.7
Developed technology	15,500		5.0
In process research and development ("IPR&D")	1,540		Various
Trade name	900		5.0
Backlog	1,100		0.3
Total identifiable intangible assets	$	40,240

Customer relationships represent the fair value of established relationships with original equipment manufacturers and distributors. Developed technology primarily represents the fair value of acquired AATI patented and unpatented technologies related to product designs. IPR&D represents the fair value of incomplete AATI research and development projects that had not reached technological feasibility but are expected to generate future economic benefit as of the acquisition date, January 9, 2012. Because of the uncertainty related to the completion of these projects, the Company has determined that the amortization period will be established when the projects reach technological feasibility or are discontinued. If a project is discontinued or fails to meet technological feasibility, the value associated with that project will be written off in the period the determination is made. The trade name represents the brand and name recognition associated with the marketing of AATI products and was determined to have a finite life. Backlog represents the fair value of AATI unfilled firm orders as of the acquisition date. All intangible assets acquired in connection with the AATI acquisition will be amortized on a straight-line basis over their respective weighted average amortization period. The estimated fair values of the intangible assets acquired were primarily determined using the income approach based on significant inputs that were not observed. The Company considers the fair value of each of the acquired intangible assets to be Level 3 assets due to the significant estimates and assumptions used by management in establishing the estimated fair values. See Note 4, Fair Value in these Notes to Consolidated Financial Statements for the definition of Level 3 assets.

Net revenue and net income for AATI have been included in the consolidated statements of operations from the acquisition date through the end of the fiscal quarter on March 30, 2012. The impact of AATI's ongoing operations on the Company's net revenue and net income were insignificant to the three and six months ended March 30, 2012. The Company recognized transaction related costs associated with the AATI acquisition of approximately $9.2 million, including arbitration costs, during the six months ended March 30, 2012.

The unaudited pro forma financial results for the six months ended March 30, 2012 and April 1, 2011 combine the unaudited historical results of Skyworks with the unaudited historical results of AATI for the six months ended March 30, 2012 and April 1, 2011, respectively. The results include the effects of unaudited pro forma adjustments as if AATI was acquired at the beginning of the prior fiscal year, October 2, 2010. The unaudited pro forma results presented include amortization charges for acquired intangible assets, adjustments for increases in the fair value of acquired inventory, other charges and related tax effects. The pro forma financial results presented below do not include any anticipated synergies or other expected benefits of the acquisition. These unaudited results are presented for informational purposes only and are not necessarily indicative of future operations (in thousands, except per share amounts):



	Six-months Ended
	March 30, 2012		April 1, 2011
Revenue	$	774,870	$	705,122
Net income	$	104,915	$	64,654
Diluted EPS	$	0.55	$	0.34

Marketable Securities	6 Months Ended
Marketable Securities	Mar. 30, 2012
Marketable Securities [Abstract]
MARKETABLE SECURITIES	MARKETABLE SECURITIES The Company accounts for its investment in marketable securities in accordance with ASC 320-Investments-Debt and Equity Securities, and classifies them as “available for sale.” At March 30, 2012, these securities included $4.0 million of par value auction rate securities ("ARS"), with a carrying value of $3.1 million as compared to the September 30, 2011 balances of $3.2 million and $2.3 million, respectively. The increase in the balances held at March 30, 2012 relates to ARS recognized in the acquisition of AATI with a par and carrying value of approximately $0.8 million. The difference between the par and carrying values is categorized as a temporary loss in other comprehensive income. The Company receives the scheduled interest payments in accordance with the terms of the securities and evaluates the appropriate accounting treatment in each period presented. In addition to the ARS, the Company acquired $20.9 million in US treasury bills from AATI. These securities matured or were sold during the three months ended March 30, 2012.

Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Mar. 30, 2012
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Legal Matters From time to time, various lawsuits, claims and proceedings have been, and may in the future be, instituted or asserted against the Company, including those pertaining to patent infringement, intellectual property, environmental, product liability, safety and health, employment and contractual matters. Additionally, the semiconductor industry is characterized by vigorous protection and pursuit of intellectual property rights. From time to time, third parties have asserted and may in the future assert patent, copyright, trademark and other intellectual property rights to technologies that are important to the Company's business and have demanded and may in the future demand that the Company license their technology. The outcome of any such litigation cannot be predicted with certainty and some such lawsuits, claims or proceedings may be disposed of unfavorably to the Company. Generally speaking, intellectual property disputes often have a risk of injunctive relief, which, if imposed against the Company, could materially and adversely affect the Company's financial condition, or results of operations. From time to time the Company may also be involved in legal proceedings in the ordinary course of business. On June 6 and 7, 2011, two putative stockholder class action lawsuits (Case No. 111CV202403 (the “Bushansky action”) and Case No. 111CV202501 (the “Venette action”), respectively) were filed in California Superior Court in Santa Clara County naming AATI, members of AATI's board of directors, the Company and PowerCo Acquisition Corp. (“Merger Sub”) as defendants. The lawsuits related to conduct surrounding the Company's acquisition of AATI. On July 26, 2011, the Court issued an order consolidating the Bushansky action and Venette action into a single, consolidated action captioned In re Advanced Analogic Technologies Inc. Shareholder Litigation, Lead Case No. 111CV202403, and designating an amended complaint filed on July 14, 2011 in the Venette action as the operative complaint in the litigation. On November 30, 2011, following confidential arbitration proceedings in the Delaware Court of Chancery, the Company announced that it and AATI had amended their previously announced merger agreement whereby the Company would acquire AATI at a reduced price through a tender offer. The Company and AATI completed the transaction on January 9, 2012. On March 2, 2012, the Court stayed all discovery in the matter and ordered that Plaintiffs file an amended complaint by April 20, 2012. On April 20, 2012, Plaintiffs filed an amended complaint (“First Amended Complaint”) against each of the original defendants with the exception of Merger Sub. The First Amended Complaint alleges, among other things, that (1) members of AATI's board of directors breached their fiduciary duties by (a) failing to take steps to maximize the value of AATI to its public shareholders by failing to adequately consider potential acquirers, (b) agreeing to the merger for inadequate consideration on unfair terms; (c) causing the filing of a materially misleading Schedule 14D-9 that failed to (i) disclose a basis for the price reduction, (ii) describe the arbitration proceedings, and (iii) include any financial valuation or fairness opinion concerning whether the revised merger consideration was fair; and (d) causing the issuance of amendments to the Schedule 14D-9 that failed to respond adequately to the SEC's disclosure directives; and (2) Skyworks and AATI allegedly aided and abetted these purported breaches of fiduciary duties. Although there can be no assurance of a favorable outcome, the Company believes the claims made by other parties in the foregoing matters are without merit and will vigorously defend the actions. The Company has not recorded any accrual at March 30, 2012 for contingent liabilities associated with the legal proceedings described above based on the Company's assessment that a liability, while possible, is not probable. At the time of this filing, the Company determined there is a reasonably possible, but not probable, range of possible aggregate losses related to outstanding legal matters which the Company has assessed and determined to be immaterial to the results of operations and liquidity position. The Company monitors the status of these contingencies on an ongoing basis to ensure amounts are recognized and/or disclosed in our financial statements and footnotes as required by ASC450, Loss Contingencies. Guarantees and Indemnifications The Company has made no contractual guarantees for the benefit of third parties. However, the Company generally indemnifies its customers from third-party intellectual property infringement litigation claims related to its products, and, on occasion, also provides other indemnities related to product sales. In connection with certain facility leases, the Company has indemnified its lessors for certain claims arising from the Company's activities at the facility or out of the lease. The Company indemnifies its directors and officers to the maximum extent permitted under the laws of the state of Delaware. The duration of the indemnities varies, and in many cases is indefinite. The indemnities to customers in connection with product sales generally are subject to limits based upon the amount of the related product sales and in many cases are subject to geographic and other restrictions. In certain instances, the Company's indemnities do not provide for any limitation of the maximum potential future payments the Company could be obligated to make. The Company has not recorded any liability for these indemnities in the accompanying consolidated balance sheets and does not expect that such obligations will have a material adverse impact on its financial condition or results of operations.

Common Stock Repurchase	6 Months Ended
Common Stock Repurchase	Mar. 30, 2012
Stockholders' Equity Note [Abstract]
COMMON STOCK REPURCHASE	COMMON STOCK REPURCHASE On August 3, 2010, the Board of Directors approved a stock repurchase program, pursuant to which the Company is authorized to repurchase up to $200.0 million of the Company's common stock from time to time on the open market or in privately negotiated transactions, as permitted by securities laws and other legal requirements. The Company did not repurchase any shares during the three months ended March 30, 2012. During the six months ended March 30, 2012, the Company paid approximately $12.4 million (including commissions) in connection with the repurchase of 750,000 shares of its common stock (paying an average price of $16.54 per share). As of March 30, 2012, $117.6 million remained available under the existing share repurchase authorization.

Description Of Business and Basis Of Presentation (Details)	3 Months Ended		12 Months Ended
	Mar. 30, 2012 weeks	Apr. 01, 2011 weeks	Sep. 28, 2012 weeks	Sep. 30, 2011 weeks
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Fiscal Period Number Of Weeks In Fiscal Year			52	52
Fiscal Period Number of Weeks in Fiscal Quarter	13	13

Business Combinations (Narrative) (Details) (USD $)	Mar. 30, 2012	Jan. 09, 2012
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
AATI [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 277,344,000
Acquired Goodwill		138,796,000
Business Acquisition, Cost of Acquired Entity, Transaction Costs	$ 9,200,000

Business Combinations (Schedule of Estimated Fair Values of Assets Acquired) (Details) (AATI [Member], USD $) In Thousands, unless otherwise specified	Jan. 09, 2012
AATI [Member]
Business Acquisition [Line Items]
Acquired Cash	$ 42,605
Acquired Short-term Investments	20,900
Acquired Accounts Receivable, Net	10,712
Acquired Inventory	15,470
Acquired Deferred Tax Assets	18,358
Acquired Property, Plant and Equipment, Net	3,888
Acquired Other Assets	2,139
Acquired Identifiable Intangible Assets	40,240
Acquired Goodwill	138,796
Acquired Total Assets	293,108
Acquired Liabilities Assumed	(15,764)
Business Combination, Consideration Transferred	$ 277,344

Business Combinations (Schedule of Acquired Intangible Assets) (Details) (AATI [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2012 Y	Jan. 09, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount		$ 40,240
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount		21,200
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	4.7
DevelopedTechnology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount		15,500
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	5.0
In-Process Research and Development [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount		1,540
Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount		900
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	5.0
Backlog [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount		$ 1,100
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	0.3

Marketable Securities (Details) (USD $)	Mar. 30, 2012	Jan. 09, 2012	Sep. 30, 2011
Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value, auction rate securities	$ 4,000,000		$ 3,200,000
Carrying value, auction rate securities	3,100,000		2,300,000
Acquired Short-term Investments		800,000
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Acquired Short-term Investments		$ 20,900,000

Fair Value (Schedule Of Financial Instruments Measured At Fair Value On Recurring Basis) (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Mar. 30, 2012	Sep. 30, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market	$ 221,611
Auction rate securities	3,093	2,288
Total	224,704
Contingent consideration liability recorded for business combinations	59,400
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market	221,611
Auction rate securities	0
Total	221,611
Contingent consideration liability recorded for business combinations	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market	0
Auction rate securities	0
Total	0
Contingent consideration liability recorded for business combinations	0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market	0
Auction rate securities	3,093
Total	3,093
Contingent consideration liability recorded for business combinations	$ 59,400	$ 59,400

Fair Value (Fair Value Reconciliation of Unobservable Inputs) (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2012	Sep. 30, 2011
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Available-for-sale Securities, Fair Value Disclosure		$ 2,288
Business Acquisition, Contingent Consideration, at Fair Value	59,400
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	805
Available-for-sale Securities, Fair Value Disclosure	3,093	2,288
Business Acquisition, Contingent Consideration, at Fair Value	59,400
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Business Acquisition, Contingent Consideration, at Fair Value	59,400	59,400
Available-for-sale Securities, Fair Value Disclosure	3,093
Business Acquisition, Contingent Consideration, at Fair Value	59,400	59,400
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases	$ 0

Inventory (Schedule Of Inventories) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2012	Sep. 30, 2011
Inventory, Net [Abstract]
Inventory, Raw Materials, Net of Reserves	$ 22,504	$ 18,565
Inventory, Work in Process, Net of Reserves	94,816	92,601
Inventory, Finished Goods, Net of Reserves	70,803	73,633
Finished goods on consignment at customers	8,435	13,384
Total inventory	$ 196,558	$ 198,183

Property, Plant and Equipment (Schedule Of Property, Plant And Equipment) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2012	Sep. 30, 2011
Property, Plant and Equipment
Total property, plant and equipment, gross	$ 703,040	$ 673,238
Accumulated depreciation	450,728	421,873
Total property, plant and equipment, net	252,312	251,365
Land and improvements
Property, Plant and Equipment
Total property, plant and equipment, gross	11,572	11,024
Building and improvements
Property, Plant and Equipment
Total property, plant and equipment, gross	56,616	53,397
Furniture and fixtures
Property, Plant and Equipment
Total property, plant and equipment, gross	26,861	26,325
Machinery and equipment
Property, Plant and Equipment
Total property, plant and equipment, gross	586,437	568,563
Construction in progress
Property, Plant and Equipment
Total property, plant and equipment, gross	$ 21,554	$ 13,929

Goodwill and Intangible Assets (Changes in Carrying Amount of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Mar. 30, 2012
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 663,041
Goodwill, Impairment Loss	0
Goodwill, Acquired During Period	138,796
Goodwill, Other Changes	980
Goodwill	$ 802,817

Goodwill and Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Mar. 30, 2012 Y	Sep. 30, 2011
Finite-Lived Intangible Assets [Line Items]
Total intangible assets, Gross Carrying Amount	$ 175,695	$ 135,935
Total intangible assets, Accumulated Amortization	(64,592)	(49,127)
Total intangible assets, Net Carrying Amount	111,103	86,808
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortized intangible assets, Weighted Average Amortization Period Remaining (Years)	3.2
Amortized intangible assets, Gross Carrying Amount	87,066	70,046
Amortized intangible assets, Accumulated Amortization	(34,706)	(27,039)
Amortized intangible assets, Net Carrying Amount	52,360	43,007
In-Process Research and Development [Member]
Finite-Lived Intangible Assets [Line Items]
Amortized intangible assets, Gross Carrying Amount	6,050	4,510
Amortized intangible assets, Accumulated Amortization	(1,314)	(260)
Amortized intangible assets, Net Carrying Amount	4,736	4,250
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amortized intangible assets, Weighted Average Amortization Period Remaining (Years)	3.4
Amortized intangible assets, Gross Carrying Amount	78,710	57,510
Amortized intangible assets, Accumulated Amortization	(28,572)	(21,828)
Amortized intangible assets, Net Carrying Amount	50,138	35,682
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Indefinite-Lived Trademarks	3,869	3,869
Nonamortizing intangible assets, Gross Carrying Amount	3,869	3,869
Total intangible assets, Accumulated Amortization	$ 0	$ 0

Goodwill And Intangible Assets (Schedule Of Expected Annual Amortization Expense Related To Intangible Assets For The Next Five Years) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2012
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
Amortization expense, 2012	$ 16,732
Amortization expense, 2013	28,445
Amortization expense, 2014	23,371
Amortization expense, 2015	20,466
Amortization expense, 2016	16,247
Future Amortization Expense, after Year Five	$ 1,973

Borrowing Arrangements (Narrative) (Details) (USD $)	6 Months Ended
Borrowing Arrangements (Narrative) (Details) (USD $)	Mar. 30, 2012	Sep. 30, 2011	Mar. 02, 2007 tranches
Debt Instrument [Line Items]
Principal amount of convertible subordinated notes issued	$ 0	$ 26,677,000	$ 200,000,000
Debt Offering Number of Tranches			2
Extinguishment of Debt, Amount	26,700,000
Convertible debt Premium Paid Upon Retirement	21,400,000
Convertible Subordinated Notes 1.25% due March 2010 [Member]
Debt Instrument [Line Items]
Principal amount of convertible subordinated notes issued			100,000,000
Percentage of convertible subordinated notes			1.25%
Convertible Subordinated Notes 1.50% Due March 2012 [Member]
Debt Instrument [Line Items]
Principal amount of convertible subordinated notes issued			$ 100,000,000
Percentage of convertible subordinated notes			1.50%

(Schedule Additional Information About The Company's Convertible Notes) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2012	Sep. 30, 2011	Mar. 02, 2007
Debt Instrument [Line Items]
Equity component of the convertible notes outstanding	$ 0	$ 6,061
Principal amount of convertible subordinated notes issued	0	26,677	200,000
Unamortized discount of the liability component	0	588
Net carrying amount of the liability component	$ 0	$ 26,089

Income Taxes (Narrative) (Details) (USD $)	3 Months Ended
Income Taxes (Narrative) (Details) (USD $)	Mar. 30, 2012	Apr. 01, 2011
Income Tax Examination [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	35.00%
Federal research and development tax credits		$ 4,800,000
Valuation Allowance, Amount	44,800,000
Deferred Taxes, Business Combination, Valuation Allowance, Available to Reduce Income Tax Expense	11,600,000
Future Taxable Income to Recognize Deferred Tax Assets	217,034,000
Unrecognized Tax Benefits, Increases Resulting from Current Period Tax Positions	12,005,000
Unrecognized Tax Benefits	48,022,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	34,174,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	200,000
State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Valuation Allowance, Amount	31,500,000
Foreign Country [Member]
Income Tax Examination [Line Items]
Valuation Allowance, Amount	13,300,000
AATI [Member]
Income Tax Examination [Line Items]
Unrecognized Tax Benefits	9,674,000
AATI [Member] \| State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Valuation Allowance, Amount	$ 5,500,000

Common Stock Repurchase (Details) (USD $)	6 Months Ended
Common Stock Repurchase (Details) (USD $)	Mar. 30, 2012	Apr. 01, 2011	Aug. 30, 2010
Stockholders' Equity Note [Abstract]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased			$ 200,000,000
Payments for Repurchase of Common Stock	12,405,000	41,564,000
Treasury Stock, Shares, Acquired	750,000
Treasury Stock Acquired, Average Cost Per Share	$ 16.54
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 117,600,000

Restructuring and Other Charges (Details) (USD $)	3 Months Ended		6 Months Ended
Restructuring and Other Charges (Details) (USD $)	Mar. 30, 2012	Apr. 01, 2011	Mar. 30, 2012	Apr. 01, 2011
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 5,895,000	$ 0	$ 6,615,000	$ 0
Payments for Restructuring	(3,400,000)		(4,332,000)
Restructuring and Related Cost, Expected Cost	6,300,000
Restructuring Reserve [Roll Forward]
Restructuring Reserve			2,028,000
Restructuring Charges	5,895,000	0	6,615,000	0
Payments for Restructuring	(3,400,000)		(4,332,000)
Restructuring Reserve, Accrual Adjustment			4,000
Restructuring Reserve	4,315,000		4,315,000
Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			440,000
Payments for Restructuring			(97,000)
Restructuring Reserve [Roll Forward]
Restructuring Reserve			819,000
Restructuring Charges			440,000
Payments for Restructuring			(97,000)
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve	1,162,000		1,162,000
license and software write-downs and other [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0
Payments for Restructuring			(212,000)
Restructuring Reserve [Roll Forward]
Restructuring Reserve			707,000
Restructuring Charges			0
Payments for Restructuring			(212,000)
Restructuring Reserve, Accrual Adjustment			4,000
Restructuring Reserve	499,000		499,000
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			6,175,000
Payments for Restructuring			(4,023,000)
Restructuring Reserve [Roll Forward]
Restructuring Reserve			502,000
Restructuring Charges			6,175,000
Payments for Restructuring			(4,023,000)
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve	2,654,000		2,654,000
AATI Restucturing [Member] \| Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	440,000
Restructuring Reserve [Roll Forward]
Restructuring Charges	440,000
AATI Restucturing [Member] \| Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	5,500,000
Restructuring Reserve [Roll Forward]
Restructuring Charges	5,500,000
SiGe Restructure [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			700,000
Restructuring Reserve [Roll Forward]
Restructuring Charges			$ 700,000