F5 (FFIV) 10-K 15 Nov 22 2022 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Sep. 30, 2022	Nov. 07, 2022	Mar. 31, 2022
Cover [Abstract]
Entity Central Index Key	0001048695
Document Type	10-K
Document Annual Report	true
Document Period End Date	Sep. 30, 2022
Document Transition Report	false
Entity File Number	000-26041
Entity Registrant Name	F5, Inc.
Entity Incorporation, State or Country Code	WA
Entity Tax Identification Number	91-1714307
Entity Address, Address Line One	801 5th Avenue
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98104
City Area Code	206
Local Phone Number	272-5555
Title of 12(b) Security	Common stock, no par value
Trading Symbol	FFIV
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 12,578,190,940
Entity Common Stock, Shares Outstanding		60,368,610
Documents Incorporated by Reference [Text Block]	Information required in response to Part III of this Form 10-K (Items 10, 11, 12, 13 and 14) is hereby incorporated by reference to the specified portions of the Registrant’s Definitive Proxy Statement for the Annual Shareholders Meeting for fiscal year 2022, which Definitive Proxy Statement shall be filed with the Securities and Exchange Commission pursuant to Regulation 14A within 120 days of the end of the fiscal year to which this Report relates
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--09-30
Amendment Flag	false

Auditor Information

Auditor Information	12 Months Ended
	Sep. 30, 2022
Cover [Abstract]
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Seattle, Washington
Auditor Firm ID	238

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
ASSETS
Cash and cash equivalents	$ 758,012	$ 580,977
Short-term investments	126,554	329,630
Accounts receivable, net of allowances of $6,020 and $3,696	469,979	340,536
Inventories	68,365	22,055
Other current assets	489,314	337,902
Total current assets	1,912,224	1,611,100
Property and equipment, net	168,182	191,164
Operating lease right-of-use assets	227,475	244,934
Long-term investments	9,544	132,778
Deferred tax assets	183,365	128,193
Goodwill	2,259,282	2,216,553
Other assets, net	516,122	472,558
Total assets	5,276,194	4,997,280
LIABILITIES AND SHAREHOLDERS’ EQUITY
Accounts payable	113,178	62,096
Accrued liabilities	309,819	341,487
Deferred revenue	1,067,182	968,669
Current portion of long-term debt	349,772	19,275
Total current liabilities	1,839,951	1,391,527
Deferred tax liabilities	2,781	2,414
Deferred revenue, long-term	624,398	521,173
Operating lease liabilities, long-term	272,376	296,945
Long-term debt	0	349,772
Other long-term liabilities	67,710	75,236
Total long-term liabilities	967,265	1,245,540
Commitments and contingencies (Note 12)
Shareholders’ equity
Preferred stock, no par value; 10,000 shares authorized, no shares outstanding	0	0
Common stock, no par value; 200,000 shares authorized, 59,860 and 60,652 shares issued and outstanding	91,048	192,458
Accumulated other comprehensive loss	(26,176)	(20,073)
Retained earnings	2,404,106	2,187,828
Total shareholders’ equity	2,468,978	2,360,213
Total liabilities and shareholders’ equity	$ 5,276,194	$ 4,997,280

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Statement of Financial Position [Abstract]
Accounts receivable, allowances	$ 6,020	$ 3,696
Preferred stock, par value (USD per share)	$ 0	$ 0
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value (USD per share)	$ 0	$ 0
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	59,860,000	60,652,000
Common stock, shares outstanding	59,860,000	60,652,000

Consolidated Income Statements

Consolidated Income Statements - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Net revenues
Net revenues	$ 2,695,845	$ 2,603,416	$ 2,350,822
Cost of net revenues
Cost of net revenues	539,627	493,146	407,887
Gross profit	2,156,218	2,110,270	1,942,935
Operating expenses
Sales and marketing	926,591	929,983	843,178
Research and development	543,368	512,627	441,324
General and administrative	274,558	273,635	258,366
Restructuring charges	7,909	0	7,800
Total	1,752,426	1,716,245	1,550,668
Income from operations	403,792	394,025	392,267
Other (expense) income, net	(18,399)	(7,088)	4,130
Income before income taxes	385,393	386,937	396,397
Provision for income taxes	63,233	55,696	88,956
Net income	$ 322,160	$ 331,241	$ 307,441
Net income per share - basic (USD per share)	$ 5.34	$ 5.46	$ 5.05
Weighted average shares - basic (shares)	60,274	60,707	60,911
Net income per share - diluted (USD per share)	$ 5.27	$ 5.34	$ 5.01
Weighted average shares - diluted (shares)	61,097	62,057	61,378
Product [Member]
Net revenues
Net revenues	$ 1,317,117	$ 1,247,084	$ 1,025,856
Cost of net revenues
Cost of net revenues	319,713	286,293	215,275
Service [Member]
Net revenues
Net revenues	1,378,728	1,356,332	1,324,966
Cost of net revenues
Cost of net revenues	$ 219,914	$ 206,853	$ 192,612

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income Statement - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 322,160	$ 331,241	$ 307,441
Other comprehensive (loss) income:
Foreign currency translation adjustment	(4,502)	(68)	(572)
Available-for-sale securities:
Unrealized (losses) gains on securities, net of taxes of $(160), $(234), and $76 for the years ended September 30, 2022, 2021, and 2020, respectively	(1,449)	(1,557)	809
Reclassification adjustment for realized (losses) gains included in net income, net of taxes of $48, $(69), and $(65) for the years ended September 30, 2022, 2021, and 2020, respectively	(152)	268	237
Net change in unrealized (losses) gains on available-for-sale securities, net of tax	(1,601)	(1,289)	1,046
Total other comprehensive (loss) income	(6,103)	(1,357)	474
Comprehensive income	$ 316,057	$ 329,884	$ 307,915

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax	$ (160)	$ (234)	$ 76
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax	$ 48	$ (69)	$ (65)

Consolidated Statement Of Share

Consolidated Statement Of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Accumulated Other Comprehensive Loss	Retained Earnings
Balance, shares at Sep. 30, 2019		60,367,000
Balance at Sep. 30, 2019	$ 1,761,497	$ 142,597	$ (19,190)	$ 1,638,090
Exercise of employee stock options	2,596	$ 2,596
Exercise of employee stock options, shares		104,000
Issuance of stock under employee stock purchase plan	50,239	$ 50,239
Issuance of stock under employee stock purchase plan, shares		419,000
Issuance of restricted stock, shares		1,027,000
Repurchase of common stock	(100,016)	$ (100,016)
Repurchase of common stock, shares		(799,000)
Taxes paid related to net share settlement of equity awards	(2,536)	$ (2,536)
Taxes paid related to net share settlement of equity awards, shares		(19,000)
Stock-based compensation	212,573	$ 212,573
Net income	307,441			307,441
Other comprehensive income (loss)	474		474
Balance, shares at Sep. 30, 2020		61,099,000
Balance at Sep. 30, 2020	2,232,268	$ 305,453	(18,716)	1,945,531
Exercise of employee stock options	4,864	$ 4,864
Exercise of employee stock options, shares		164,000
Issuance of stock under employee stock purchase plan	60,888	$ 60,888
Issuance of stock under employee stock purchase plan, shares		542,000
Issuance of restricted stock, shares		1,430,000
Repurchase of common stock	(500,000)	$ (411,056)		(88,944)
Repurchase of common stock, shares		(2,501,000)
Taxes paid related to net share settlement of equity awards	(14,032)	$ (14,032)
Taxes paid related to net share settlement of equity awards, shares		(82,000)
Stock-based compensation	246,341	$ 246,341
Net income	331,241			331,241
Other comprehensive income (loss)	$ (1,357)		(1,357)
Balance, shares at Sep. 30, 2021	60,652,000	60,652,000
Balance at Sep. 30, 2021	$ 2,360,213	$ 192,458	(20,073)	2,187,828
Exercise of employee stock options	$ 3,613	$ 3,613
Exercise of employee stock options, shares	143,128	143,000
Issuance of stock under employee stock purchase plan	$ 60,927	$ 60,927
Issuance of stock under employee stock purchase plan, shares		412,000
Issuance of restricted stock, shares		1,368,000
Repurchase of common stock	(500,023)	$ (394,141)		(105,882)
Repurchase of common stock, shares		(2,611,000)
Taxes paid related to net share settlement of equity awards	(21,025)	$ (21,025)
Taxes paid related to net share settlement of equity awards, shares		(104,000)
Stock-based compensation	249,216	$ 249,216
Net income	322,160			322,160
Other comprehensive income (loss)	$ (6,103)		(6,103)
Balance, shares at Sep. 30, 2022	59,860,000	59,860,000
Balance at Sep. 30, 2022	$ 2,468,978	$ 91,048	$ (26,176)	$ 2,404,106

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Operating activities
Net income	$ 322,160	$ 331,241	$ 307,441
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	249,216	243,279	201,948
Depreciation and amortization	115,609	115,424	95,857
Non-cash operating lease costs	38,735	38,375	39,139
Deferred income taxes	(40,244)	(76,930)	7,293
Impairment of assets	6,175	40,698	9,673
Other	1,267	737	2,122
Changes in operating assets and liabilities (excluding effects of the acquisition of businesses):
Accounts receivable	(130,605)	(46,289)	46,502
Inventories	(46,310)	5,843	6,503
Other current assets	(144,628)	(84,328)	(49,895)
Other assets	(87,008)	(110,653)	(25,690)
Accounts payable and accrued liabilities	19,163	22,933	34,742
Deferred revenue	191,147	216,431	35,514
Lease liabilities	(52,046)	(51,565)	(50,251)
Net cash provided by operating activities	442,631	645,196	660,898
Investing activities
Purchases of investments	(61,284)	(472,165)	(584,240)
Maturities of investments	260,357	197,279	543,065
Sales of investments	120,578	271,521	309,687
Acquisition of businesses, net of cash acquired	(67,911)	(411,319)	(955,574)
Purchases of property and equipment	(33,624)	(30,651)	(59,940)
Net cash provided by (used in) investing activities	218,116	(445,335)	(747,002)
Financing activities
Proceeds from the exercise of stock options and purchases of stock under employee stock purchase plan	64,540	65,752	52,835
Repurchase of common stock	(500,023)	(500,000)	(100,016)
Proceeds from term debt agreement	0	0	400,000
Payments on term debt agreement	(20,000)	(20,000)	(10,000)
Payments for debt issuance costs	0	0	(3,040)
Taxes paid related to net share settlement of equity awards	(21,025)	(14,032)	(2,536)
Net cash (used in) provided by financing activities	(476,508)	(468,280)	337,243
Net increase (decrease) in cash, cash equivalents and restricted cash	184,239	(268,419)	251,139
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations	(6,365)	(74)	(567)
Cash, cash equivalents and restricted cash, beginning of year	584,333	852,826	602,254
Cash, cash equivalents and restricted cash, end of year	762,207	584,333	852,826
Supplemental disclosures of cash flow information
Cash paid for taxes, net of refunds	110,036	99,378	80,236
Cash paid for amounts included in the measurement of operating lease liabilities	58,592	61,504	60,564
Cash paid for interest on long-term debt	7,981	5,280	6,568
Supplemental disclosures of non-cash activities
Right-of-use assets obtained in exchange for lease obligations	$ 20,778	$ 13,051	$ 402,007

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	12 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	Summary of Significant Accounting Policies The Company F5, Inc. (the "Company") is a leading provider of multi-cloud application security and delivery solutions which enable its customers to develop, deploy, operate, secure, and govern applications in any architecture, from on-premises to the public cloud. The Company's cloud, software, and hardware solutions enable its customers to deliver digital experiences to their customers faster, reliably, and at scale. The Company's enterprise-grade application services are available as cloud-based, software-as-a-service, and software-only solutions optimized for multi-cloud environments, with modules that can run independently, or as part of an integrated solution on its high-performance appliances. In connection with its solutions, the Company offers a broad range of professional services, including consulting, training, installation, maintenance, and other technical support services. On October 1, 2021, the Company completed its acquisition of Threat Stack, Inc. ("Threat Stack"), a provider of cloud security and workload protection solutions. Accounting Principles The Company’s consolidated financial statements and accompanying notes are prepared on the accrual basis of accounting in accordance with generally accepted accounting principles in the United States of America (GAAP). Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. Use of Estimates and Assumptions The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Examples of estimates and assumptions include: revenue recognition, identifying and evaluating the performance obligations of contracts with non-standard terms, and the allocation of purchase consideration based on the relative fair value standalone sales price of these performance obligations; business combinations, including the determination of fair value for acquired developed technology assets and the evaluation and selection of significant assumptions such as revenue growth rate and technology migration curve; and the incremental borrowing rate for measuring lease obligations. Actual results may differ materially from management's estimates and assumptions. Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with original maturities of three months or less to be cash equivalents. The Company invests its cash and cash equivalents in deposits with four major financial institutions, which, at times, exceed federally insured limits. The Company has not experienced any losses on its cash and cash equivalents. Amounts included in restricted cash represent those for which the Company's use is restricted by a contractual agreement. Investments The Company classifies its debt investments as available-for-sale. Debt investments, consisting of certificates of deposit, corporate and municipal bonds and notes, the United States government and agency securities and international government securities are reported at fair value with the related unrealized gains and losses included as a component of accumulated other comprehensive income (loss) in shareholders’ equity. Realized gains and losses, credit allowances and impairments due to credit losses are included in other income (expense) in the Company’s consolidated income statements. Debt investments with maturities of less than one year or where management’s intent is to use the investments to fund current operations are classified as short-term investments. Debt investments with maturities of greater than one year are classified as long-term investments. As an approximation to fair value, equity investments are measured using net asset value (“NAV”) and are classified as long-term investments. Unrealized and realized gains and losses are recorded in other income (expense) in the Company's consolidated income statements. Accounts Receivable Trade accounts receivable are recorded at the invoiced amount, net of allowances for credit losses for any potential uncollectible amounts. The allowance for credit losses is based on the assessment of the collectability of accounts. Management regularly reviews the adequacy of the allowance for credit losses on a collective basis by considering the age of each outstanding invoice, each customer’s expected ability to pay and collection history, current market conditions, and reasonable and supportable forecasts of future economic conditions to determine whether the allowance is appropriate. Accounts receivable deemed uncollectible are charged against the allowance for credit losses when identified. For fiscal years ended September 30, 2022 and 2021, the allowance for credit losses was not material. Unbilled Receivables Unbilled receivables represent amounts related to the Company's unconditional right to consideration associated with contracts with customers that have not yet been billed. Unbilled receivables are converted to accounts receivable at the point in time when the Company has the contractual right to invoice its customers. As of September 30, 2022, unbilled receivables that are expected to be reclassified to accounts receivable within the next 12 months are included in other current assets, with those expected to be transferred to accounts receivables in more than 12 months included in other assets. Concentration of Credit Risk The Company extends credit to customers and is therefore subject to credit risk. The Company performs initial and ongoing credit evaluations of its customers’ financial condition and does not require collateral. An allowance for credit losses is recorded for any potential uncollectible amount. Estimates are used in determining the allowance for credit losses in accordance with the Accounts Receivable policy. See Note 15 - Segment Information, for disaggregated accounts receivable by significant customer. The Company maintains its cash and investment balances with high credit quality financial institutions. Fair Value of Financial Instruments Short-term and long-term investments are recorded at fair value as the underlying securities are classified as available-for-sale with any unrealized gains or losses being recorded to other comprehensive income (or loss). The fair value for securities held is determined using quoted market prices, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency. Inventories The Company outsources the manufacturing of its pre-configured hardware platforms to contract manufacturers, who assemble each product to the Company’s specifications. As protection against component shortages and to provide replacement parts for its service teams, the Company also stocks limited supplies of certain key product components. The Company reduces inventory to net realizable value based on excess and obsolete inventories determined primarily by historical usage and forecasted demand. Inventories consist of hardware and related component parts and are recorded at the lower of cost and net realizable value (as determined by the first-in, first-out method). Property and Equipment Property and equipment are stated at net book value. Depreciation of property and equipment is provided using the straight-line method over the estimated useful lives of the assets, ranging from two Business Combinations The Company’s business combinations are accounted for under the acquisition method. Management allocates the fair value of purchase consideration to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the acquisition date. The excess of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. Such valuations require management to make significant estimates and assumptions, especially with respect to intangible assets. On October 1, 2021, the Company completed its acquisition of Threat Stack, Inc. for a total purchase price of $68.9 million, of which $11.4 million of finite-lived developed technology was recorded. Goodwill Goodwill represents the excess purchase price over the estimated fair value of net assets acquired as of the acquisition date. The Company tests goodwill for impairment on an annual basis and between annual tests when impairment indicators are identified, and goodwill is written down when impaired. For its annual goodwill impairment test in all periods to date, the Company has operated under one reporting unit and the fair value of its reporting unit has been determined by the Company’s enterprise value. The Company performs its annual goodwill impairment test during the second fiscal quarter. For its annual impairment test performed in the second quarter of fiscal 2022, the Company completed a quantitative assessment and determined that there was no impairment of goodwill. The Company also considered potential impairment indicators of goodwill at September 30, 2022 and noted no indicators of impairment. Intangible Assets Intangible assets with finite lives consist of acquired developed technology, customer relationships, patents and trademarks, trade names, and non-compete covenants acquired through business combinations or asset acquisitions. Intangible assets acquired through business combinations are recorded at their respective estimated fair values upon acquisition close. Other intangible assets acquired through asset acquisitions are recorded at their respective cost. The Company determines the estimated useful lives for acquired intangible assets based on the expected future cash flows associated with the respective asset. The Company's intangible assets with finite lives are amortized using the straight-line method over their estimated useful lives, ranging from two Software Development Costs The authoritative guidance requires certain internal software development costs related to software to be sold to be capitalized upon the establishment of technological feasibility. Capitalized software development costs are amortized over the remaining estimated economic life of the product. The Company's software development costs incurred subsequent to achieving technological feasibility have not been significant and, as a result, all software development costs have been expensed as research and development activities as incurred. Internal-Use Software The Company capitalizes costs incurred during the application development stage associated with the development of internal-use software systems. The capitalized costs are then amortized over the estimated useful life of the software, which is generally three Impairment of Long-Lived Assets The Company assesses the impairment of long-lived assets whenever events or changes in business circumstances indicate that the carrying amount of an asset may not be recoverable. When such events occur, management determines whether there has been impairment by comparing the anticipated undiscounted net future cash flows to the related asset’s carrying value. If impairment exists, the asset is written down to its estimated fair value. Revenue Recognition The Company sells products through distributors, resellers, and directly to end users. Revenue related to the Company's contracts with customers is recognized by following a five-step process: • Identify the contract(s) with a customer. Evidence of a contract generally consists of a purchase order issued pursuant to the terms and conditions of a distributor, reseller or end user agreement. • Identify the performance obligations in the contract. Performance obligations are identified in the Company's contracts and include hardware, hardware-based software, software-only solutions, cloud-based subscription services as well as a broad range of service performance obligations including consulting, training, installation and maintenance. • Determine the transaction price. The purchase price stated in an agreed upon purchase order is generally representative of the transaction price. The Company offers several programs in which customers are eligible for certain levels of rebates if certain conditions are met. When determining the transaction price, the Company considers the effects of any variable consideration. • Allocate the transaction price to the performance obligations in the contract. The transaction price in a contract is allocated based upon the relative standalone selling price of each distinct performance obligation identified in the contract. • Recognize revenue when (or as) the entity satisfies a performance obligation. The Company satisfies performance obligations either over time or at a point in time as discussed in further detail below. Revenue is recognized at the time the related performance obligation is satisfied by transferring control of promised products and services to a customer. Revenue is recognized net of any taxes collected, which are subsequently remitted to governmental authorities. Shipping and handling fees charged to the Company’s customers are recognized as product revenue in the period shipped and the related costs for providing these services are recorded as a cost of sale. The following is a description of the principal activities from which the Company generates revenue: Product Revenue from the sale of the Company's hardware and perpetual software products is generally recognized at a point in time when the product has been fulfilled and the customer is obligated to pay for the product. The Company also offers several products by subscription, either through term-based license agreements or as SaaS offerings. Revenue for term-based license agreements is recognized at a point in time, when the Company delivers the software license to the customer and the subscription term has commenced. For the Company's SaaS offerings, revenue is recognized ratably as the services are provided. Hardware, including the software run on those devices is considered systems revenue. Perpetual or subscription software offerings that are, or have the ability to be deployed on a standalone basis, along with the Company's SaaS offerings are considered software revenue. When rights of return are present and the Company cannot estimate returns, revenue is recognized when such rights of return lapse. Payment terms to customers are generally net 30 days to net 60 days. Global Services Revenues for post-contract customer support ("PCS") are recognized on a straight-line basis over the service contract term. PCS includes a limited period of telephone support, updates, repair or replacement of any failed product or component that fails during the term of the agreement, bug fixes and rights to upgrades, when and if available. Consulting services are customarily billed at fixed hourly rates, plus out-of-pocket expenses, and revenues are recognized as the consulting is completed. Similarly, training revenue is recognized as the training is completed. Contract Acquisition Costs Sales commissions earned by the Company's sales force are considered incremental and recoverable costs of obtaining a contract with a customer. Sales commissions for initial service contracts and subscription offerings are deferred and then amortized as an expense on a straight-line basis over the period of benefit which management has determined to be 4.5 years and 3 years, respectively. Significant Judgments The Company enters into certain contracts with customers, including flexible consumption programs and multi-year subscriptions, with non-standard terms and conditions. Management exercises significant judgment in assessing contractual terms in these arrangements to identify and evaluate performance obligations. Management allocates consideration to each performance obligation based on relative fair value using standalone selling price and recognizes associated revenue as control is transferred to the customer. Guarantees and Product Warranties In the normal course of business to facilitate sales of its products, the Company indemnifies other parties, including customers, resellers, lessors, and parties to other transactions with the Company, with respect to certain matters. The Company has agreed to hold the other party harmless against losses arising from a breach of representations or covenants, or out of intellectual property infringement or other claims made against certain parties. These agreements may limit the time within which an indemnification claim can be made and the amount of the claim. The Company has entered into indemnification agreements with its officers and directors, and the Company’s bylaws contain similar indemnification obligations to the Company’s agents. It is not possible to determine the maximum potential amount under these indemnification agreements due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement. The Company offers warranties of one year for hardware for those customers without service contracts, with the option of purchasing additional warranty coverage in yearly increments. The Company accrues for warranty costs as part of its cost of sales based on associated material product costs and technical support labor costs. Warranty expense and accrued warranty costs were not material for all periods presented. Research and Development Research and development expenses consist of salaries and related benefits of product development personnel, prototype materials and expenses related to the development of new and improved products, and an allocation of facilities, depreciation and amortization expense. Research and development expenses are reflected in the income statements as incurred. Advertising Advertising costs are expensed as incurred. The Company incurred $15.4 million, $10.0 million and $7.8 million in advertising costs during the fiscal years 2022, 2021 and 2020, respectively. Income Taxes Deferred income tax assets and liabilities are determined based upon differences between the financial statement and income tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The realization of deferred tax assets is based on historical tax positions and estimates of future taxable income. A valuation allowance is recorded when it is more-likely-than-not that some of the deferred tax assets will not be realized. The Company assesses whether tax benefits claimed or expected to be claimed on a tax return should be recorded in the financial statements. The Company may recognize the tax benefit from an uncertain tax position only if it is more-likely-than-not that the tax position will be sustained on examination by the taxing authorities, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax benefits to be recognized in the financial statements from such a position is measured as the largest amount of benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. The Company adjusts these liabilities based on a variety of factors, including the evaluation of information not previously available. These adjustments are reflected as increases or decreases to income tax expense in the period in which new information is available. The Company has made an accounting policy election to treat taxes under the global intangible low-taxed income (GILTI) provision as a current period expense. Foreign Currency The functional currency for the Company’s foreign subsidiaries is either the U.S. dollar or the local currency depending on the assessment of management. An entity’s functional currency is determined by the currency of the economic environment in which the majority of cash is generated and expended by the entity. The financial statements of all majority-owned subsidiaries and related entities, with a functional currency other than the U.S. dollar, have been translated into U.S. dollars. All assets and liabilities of the respective entities are translated at year-end exchange rates and all revenues and expenses are translated at average rates during the respective period. Translation adjustments are reported as other comprehensive income (loss) in the consolidated statements of comprehensive income. Foreign currency transaction gains and losses are a result of the effect of exchange rate changes on transactions denominated in currencies other than the functional currency, including U.S. dollars. Gains and losses on those foreign currency transactions are included in determining net income or loss for the period of exchange and are recorded in other income, net. The net effect of foreign currency gains and losses was not material during the fiscal years ended September 30, 2022, 2021 and 2020. Segments Management has determined that the Company is organized as, and operates in, one reportable operating segment: the development, marketing and sale of application security and delivery solutions which enable its customers to develop, deploy, operate, secure, and govern applications in any architecture, from on-premises to the public cloud. Stock-based Compensation The Company issues incentive awards to its employees through stock-based compensation consisting of restricted stock units (RSUs). RSUs are payable in shares of the Company’s common stock as the periodic vesting requirements are satisfied, generally over one the date of grant. The value of RSUs is determined using the intrinsic value method and is based on the number of shares granted and the quoted price of the Company’s common stock on the date of grant. The Company offers an Employee Stock Purchase Plan (ESPP) that permits eligible employees to purchase shares of the Company’s common stock at a discount. In determining the fair value of shares issued under the ESPP, the Company uses the Black-Scholes option pricing model. The assumptions within the option pricing model are based on management’s best estimates at that time, which impact the fair value of the ESPP option calculated under the Black-Scholes methodology and, ultimately, the expense that will be recognized over the life of the ESPP option. The Company has also issued stock options as replacement awards, most notably for those assumed as part of business combinations. The Company used the Black-Scholes option pricing model to determine the fair value of the stock option replacement awards. The assumptions within the option pricing model are based on management’s best estimates at that time, which impact the fair value of the option calculated under the Black-Scholes methodology and, ultimately, the expense that will be recognized over the term of the option. The Company accounts for stock-based compensation using the straight-line attribution method for recognizing compensation expense. The Company recognizes compensation expense for only the portion of stock-based awards that are expected to vest. Therefore, the Company applies estimated forfeiture rates that are derived from historical employee termination behavior. Based on historical differences with forfeitures of stock-based awards granted to the Company’s executive officers and Board of Directors versus grants awarded to all other employees, the Company has developed separate forfeiture expectations for these two groups. The Company issues incentive awards to certain current executive officers as part of its annual equity awards program. A portion of the aggregate number of RSUs issued to executive officers vest in equal quarterly increments, and a portion is subject to the Company achieving specified performance goals. In fiscal 2018, the Company's Talent and Compensation Committee adopted a new set of metrics for the performance stock awards, including (1) 50% of the annual performance stock grant is based on achieving certain annual revenue; (2) 25% of the annual performance stock grant is based on achieving an increase in annual software revenue compared to the prior year; and (3) 25% of the annual performance stock grant is based on relative total shareholder return (TSR) benchmarked to the S&P 500 index. In each case, no vesting or payment with respect to a performance goal shall occur unless a minimum threshold is met for the applicable goal. Vesting and payment with respect to the performance goal is linear above the threshold of the applicable goal and is capped at achievement of 200% above target. The Company recognizes compensation costs for awards with performance conditions and market conditions on a straight-line basis over the requisite service period for each separately vesting portion of the award and, for awards with performance conditions, when it concludes it is probable that the performance condition will be achieved. The Company reassesses the probability of vesting at each balance sheet date and adjusts compensation costs based on the probability assessment. Comprehensive Income Comprehensive income includes certain changes in equity that are excluded from net income. Specifically, unrealized gains or losses on securities and foreign currency translation adjustments. These changes are included in accumulated other comprehensive income or loss. Recently Adopted Accounting Standards In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers. The new guidance requires contract assets and contract liabilities acquired in a business combination to be recognized and measured by the acquirer on the acquisition date in accordance with ASC 606, Revenue from Contracts with Customers. The Company early adopted this accounting standard update beginning in the first quarter of fiscal 2022 and it did not have a material impact on the Company's consolidated financial statements.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Sep. 30, 2022
Revenue from Contracts with Customers [Abstract]
Revenue from Contract with Customers	Revenue from Contracts with Customers Capitalized Contract Acquisition Costs The table below shows significant movements in capitalized contract acquisition costs (current and noncurrent) for the years ended September 30, 2022, 2021, and 2020 (in thousands): 2022 2021 2020 Balance, beginning of year $ 77,836 $ 70,396 $ 59,446 Additional capitalized contract acquisition costs 37,897 41,719 43,557 Amortization of capitalized contract acquisition costs (38,513) (34,279) (32,607) Balance, end of year $ 77,220 $ 77,836 $ 70,396 Amortization of capitalized contract acquisition costs was $38.5 million, $34.3 million, and $32.6 million for the years ended September 30, 2022, 2021, and 2020, respectively, and is recorded in Sales and Marketing expense in the accompanying consolidated income statements. There was no impairment of any capitalized contract acquisition costs during any period presented. Contract Balances Timing may differ between the satisfaction of performance obligations and the invoicing and collection of amounts related to the Company's contracts with customers. Liabilities are recorded for amounts that are collected in advance of the satisfaction of performance obligations, or for contracts with customers that contain the Company's unconditional rights to consideration, for which the customer has not been billed. These liabilities are classified as current and non-current deferred revenue. The table below shows significant movements in the deferred revenue balances (current and noncurrent) for the years ended September 30, 2022, 2021, and 2020 (in thousands): 2022 2021 2020 Balance, beginning of year $ 1,489,842 $ 1,272,632 $ 1,198,116 Amounts added but not recognized as revenues 1,167,143 1,122,081 850,022 Deferred revenue acquired through acquisition of businesses 10,591 779 39,000 Revenues recognized related to the opening balance of deferred revenue (975,996) (905,650) (814,506) Balance, end of year $ 1,691,580 $ 1,489,842 $ 1,272,632 Remaining Performance Obligations Remaining performance obligations represent the amount of the transaction price under contracts with customers that are attributable to performance obligations that are unsatisfied or partially satisfied at the reporting date. The composition of unsatisfied performance obligations consists mainly of deferred service revenue, and to a lesser extent, deferred product revenue, for which the Company has an obligation to perform, and has not yet recognized as revenue in the consolidated financial statements. As of September 30, 2022, the total non-cancelable remaining performance obligations under the Company's contracts with customers was $1.7 billion and the Company expects to recognize revenues on approximately 63.1% of these remaining performance obligations over the next 12 months, 23.0% in year two, and the remaining balance thereafter. See Note 15 - Segment Information, for disaggregated revenue by significant customer and geographic region, as well as disaggregated product revenue by systems and software.

Business Combinations

Business Combinations	12 Months Ended
	Sep. 30, 2022
Business Combinations [Abstract]
Business Combinations	Business Combinations Fiscal Year 2022 Acquisition of Threat Stack, Inc. In September 2021, the Company entered into a Merger Agreement (the “Threat Stack Merger Agreement”) with Threat Stack, Inc. ("Threat Stack"), a provider of cloud security and workload protection solutions. The transaction closed on October 1, 2021 with Threat Stack becoming a wholly-owned subsidiary of F5. The addition of Threat Stack’s cloud security capabilities to F5’s application and API protection solutions is expected to enhance visibility across application infrastructure and workloads to deliver more actionable security insights for customers. Pursuant to the Threat Stack Merger Agreement, at the effective time of the Merger, the capital stock of Threat Stack and the vested outstanding and unexercised stock options in Threat Stack were cancelled and converted to the right to receive approximately $68.9 million in cash, subject to certain adjustments and conditions set forth in the Threat Stack Merger Agreement. Transaction costs associated with the acquisition were not material. As a result of the acquisition, the Company acquired all the assets and assumed all the liabilities of Threat Stack. The goodwill related to the Threat Stack acquisition is comprised primarily of expected synergies from combining operations and the acquired intangible assets that do not qualify for separate recognition. Goodwill related to the Threat Stack acquisition is not expected to be deductible for tax purposes. The results of operations of Threat Stack have been included in the Company's consolidated financial statements from the date of acquisition.  The allocated purchase consideration to assets acquired and liabilities assumed based on preliminary estimated fair values is presented in the following table (in thousands): Estimated Useful Life Assets acquired Deferred tax assets $ 14,036 Other net tangible assets acquired, at fair value 5,481 Cash, cash equivalents, and restricted cash 911 Identifiable intangible assets: Developed technology 11,400 5 years Customer relationships 4,400 5 years Goodwill 43,287 Total assets acquired $ 79,515 Liabilities assumed Deferred revenue $ (10,591) Total liabilities assumed $ (10,591) Net assets acquired $ 68,924 The initial allocation of the purchase price was based on preliminary valuations and assumptions and is subject to change within the measurement period. In fiscal 2022, the Company recorded immaterial adjustments to consideration exchanged for the purchase of Threat Stack. The Company expects to finalize the allocation of the purchase price as soon as practicable and no later than one year from the acquisition date. The developed technology intangible asset will be amortized on a straight-line basis over its estimated useful life of five years and included in cost of net product revenues. The customer relationships intangible asset will be amortized on a straight-line basis over its estimated useful life of five years and included in sales and marketing expenses. The weighted-average life of the amortizable intangible assets recognized from the Threat Stack acquisition was five years as of October 1, 2021, the date the transaction closed. The estimated useful lives for the acquired intangible assets were based on the expected future cash flows associated with the respective asset. The pro forma financial information, as well as the revenue and earnings generated by Threat Stack, were not material to the Company's operations for the periods presented. Fiscal Year 2021 Acquisition of Volterra, Inc. On January 5, 2021, the Company entered into a Merger Agreement (the “Volterra Merger Agreement”) with Volterra, Inc. ("Volterra"), a provider of edge-as-a-service platform solutions. The transaction closed on January 22, 2021 with Volterra becoming a wholly-owned subsidiary of F5. With the addition of Volterra’s technology platform, F5 is creating an edge platform built for enterprises and service providers that will be security-first and app-driven with unlimited scale. Pursuant to the Volterra Merger Agreement, at the effective time of the Merger, the capital stock of Volterra and the vested outstanding and unexercised stock options in Volterra were cancelled and converted to the right to receive approximately $427.2 million in cash, subject to certain adjustments and conditions set forth in the Volterra Merger Agreement. The unvested stock options and restricted stock units in Volterra held by continuing employees of Volterra were assumed by F5, on the terms and conditions set forth in the Volterra Merger Agreement. The Company incurred $9.5 million of transaction costs associated with the acquisition which was included in General and Administrative expenses in fiscal 2021. As a result of the acquisition, the Company acquired all the assets and assumed all the liabilities of Volterra. The goodwill related to the Volterra acquisition is comprised primarily of expected synergies from combining operations and the acquired intangible assets that do not qualify for separate recognition. Goodwill related to the Volterra acquisition is not expected to be deductible for tax purposes. The results of operations of Volterra have been included in the Company's consolidated financial statements from the date of acquisition. The allocated purchase consideration to assets acquired and liabilities assumed based on preliminary estimated fair values is presented in the following table (in thousands): Estimated Useful Life Assets acquired Cash, cash equivalents, and restricted cash $ 14,012 Other tangible assets acquired, at fair value 7,499 Identifiable intangible assets: Developed technology 59,500 7 years Customer relationships 500 1 year Goodwill 350,863 Total assets acquired 432,374 Liabilities assumed (5,233) Net assets acquired $ 427,141 The measurement period for the Volterra acquisition lapsed during the second quarter of fiscal 2022. The Company recorded immaterial adjustments to consideration exchanged for the purchase of Volterra within the post-close measurement period. The developed technology intangible asset is being amortized on a straight-line basis over its estimated useful life of seven years and included in cost of net product revenues. The customer relationships intangible asset was amortized on a straight-line basis over its estimated useful life of one year and included in sales and marketing expenses. The weighted-average life of the amortizable intangible assets recognized from the Volterra acquisition was 6.95 years as of January 22, 2021, the date the transaction closed. The estimated useful lives for the acquired intangible assets were based on the expected future cash flows associated with the respective asset. The pro forma financial information, as well as the revenue and earnings generated by Volterra, were not material to the Company's operations for the periods presented. Fiscal Year 2020 Acquisition of Shape Security, Inc. On December 19, 2019, the Company entered into a Merger Agreement (the "Shape Merger Agreement") with Shape Security, Inc. ("Shape"), a provider of fraud and abuse prevention solutions. The transaction closed on January 24, 2020 with Shape becoming a wholly-owned subsidiary of F5. This acquisition brings together F5’s expertise in protecting applications across multi-cloud environments with Shape’s fraud and abuse prevention capabilities. Pursuant to the Shape Merger Agreement, at the effective time of the acquisition, the capital stock of Shape and the vested outstanding and unexercised stock options in Shape were cancelled and converted to the right to receive approximately $1.0 billion in cash, subject to certain adjustments and conditions set forth in the Shape Merger Agreement, and the unvested stock options and restricted stock units in Shape held by continuing employees of Shape were assumed by F5, on the terms and conditions set forth in the Shape Merger Agreement. Included in cash consideration was $23.2 million of transaction costs paid by F5 on behalf of Shape. In addition, the Company incurred $15.3 million of transaction costs associated with the acquisition which was included in General and Administrative expenses in fiscal 2020. As a result of the acquisition, the Company acquired all the assets and assumed all the liabilities of Shape. The goodwill related to the Shape acquisition is comprised primarily of expected synergies from combining operations and the acquired intangible assets that do not qualify for separate recognition. Goodwill related to the Shape acquisition is not expected to be deductible for tax purposes. The results of operations of Shape have been included in the Company's consolidated financial statements from the date of acquisition. The allocated purchase consideration to assets acquired and liabilities assumed is presented in the following table (in thousands): Estimated Useful Life Assets acquired Cash, cash equivalents, and restricted cash $ 53,934 Fair value of tangible assets: Accounts receivable 21,077 Deferred tax assets 29,848 Operating lease right-of-use assets 29,644 Other tangible assets 22,571 Identifiable intangible assets: Developed technology 120,000 7 years Customer relationships 21,000 4 years Trade name 9,500 5 years Goodwill 798,867 Total assets acquired $ 1,106,441 Liabilities assumed Deferred revenue $ (39,000) Operating lease liabilities (30,773) Other assumed liabilities (18,571) Total liabilities assumed $ (88,344) Net assets acquired $ 1,018,097 The measurement period for the Shape acquisition lapsed in the second quarter of fiscal 2021. The Company recorded immaterial adjustments to consideration exchanged for the purchase of Shape within the post-close measurement period. The developed technology intangible asset is being amortized on a straight-line basis over its estimated useful life of seven years and included in cost of net product revenues. The trade names and customer relationships intangible assets are being amortized on a straight-line basis over their estimated useful lives of five years and four years, respectively, and included in sales and marketing expenses. The weighted average life of the amortizable intangible assets recognized from the Shape acquisition was 6.5 years as of January 24, 2020, the date the transaction closed. The estimated useful lives for the acquired intangible assets were based on the expected future cash flows associated with the respective asset. The pro forma financial information, as well as the revenue and earnings generated by Shape, were not material to the Company's operations for the periods presented.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value MeasurementsIn accordance with the authoritative guidance on fair value measurements and disclosure under GAAP, the Company determines fair value using a fair value hierarchy that distinguishes between market participant assumptions developed based on market data obtained from sources independent of the reporting entity, and the reporting entity’s own assumptions about market participant assumptions developed based on the best information available in the circumstances and expands disclosure about fair value measurements. Fair value is the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date, essentially the exit price. The levels of fair value hierarchy are: Level 1: Quoted prices in active markets for identical assets and liabilities at the measurement date that the Company has the ability to access. Level 2: Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. Level 3: Unobservable inputs for which there is little or no market data available. These inputs reflect management’s assumptions of what market participants would use in pricing the asset or liability. Level 1 investments are valued based on quoted market prices in active markets and include the Company’s cash equivalent investments. Level 2 investments, which include investments that are valued based on quoted prices in markets that are not active, broker or dealer quotations, actual trade data, benchmark yields or alternative pricing sources with reasonable levels of price transparency, include the Company’s certificates of deposit, corporate bonds and notes, municipal bonds and notes, U.S. government securities, U.S. government agency securities and international government securities. Fair values for the Company’s level 2 investments are based on similar assets without applying significant judgments. In addition, all of the Company’s level 2 investments have a sufficient level of trading volume to demonstrate that the fair values used are appropriate for these investments. A financial instrument’s level within the fair value hierarchy is based upon the lowest level of any input that is significant to the fair value measurement. However, the determination of what constitutes “observable” requires significant judgment by the Company. The Company considers observable data to be market data which is readily available, regularly distributed or updated, reliable and verifiable, not proprietary, and provided by independent sources that are actively involved in the relevant market. Assets and Liabilities Measured and Recorded at Fair Value on a Recurring Basis The Company's financial assets measured at fair value on a recurring basis subject to the disclosure requirements at September 30, 2022 and September 30, 2021, were as follows (in thousands): Gross Unrealized Classification on Balance Sheet As of September 30, 2022 Fair Value Level Cost or Amortized Cost Gains Losses Aggregate Cash and Cash Equivalents Short-Term Investments Long-Term Investments Changes in fair value recorded in other comprehensive income Money Market Funds Level 1 $ 276,294 $ — $ — $ 276,294 $ 276,294 $ — $ — Corporate bonds and notes Level 2 50,828 — (950) 49,878 912 44,356 4,610 Municipal bonds and notes Level 2 5,018 — (102) 4,916 — 3,812 1,104 U.S. government securities Level 2 84,734 — (660) 84,074 10,120 73,954 — U.S. government agency securities Level 2 5,825 — (75) 5,750 606 4,432 712 Total debt investments $ 422,699 $ — $ (1,787) $ 420,912 $ 287,932 $ 126,554 $ 6,426 Changes in fair value recorded in other net income (expense) Equity investments * $ 3,118 $ — $ — $ 3,118 Total equity investments 3,118 — — 3,118 Total investments $ 424,030 $ 287,932 $ 126,554 $ 9,544 * The fair value of this equity investment is measured at net asset value (NAV) which approximates fair value and is not classified within the fair value hierarchy . Gross Unrealized Classification on Balance Sheet As of September 30, 2021 Fair Value Level Cost or Amortized Cost Gains Losses Aggregate Cash and Cash Equivalents Short-Term Investments Long-Term Investments Changes in fair value recorded in other comprehensive income Money Market Funds Level 1 $ 17,150 $ — $ — $ 17,150 $ 17,150 $ — $ — Certificates of deposit Level 2 255 — — 255 — 255 — Corporate bonds and notes Level 2 243,568 129 (86) 243,611 4,397 186,107 53,107 Municipal bonds and notes Level 2 24,684 2 (9) 24,677 — 13,566 11,111 U.S. government securities Level 2 162,221 14 (12) 162,223 — 102,615 59,608 U.S. government agency securities Level 2 36,053 — (14) 36,039 — 27,087 8,952 Total investments $ 483,931 $ 145 $ (121) $ 483,955 $ 21,547 $ 329,630 $ 132,778 The Company uses the fair value hierarchy for financial assets and liabilities. The carrying amounts of other current financial assets and other current financial liabilities approximate fair value due to their short-term nature. Interest income from investments was not material for the years ended September 30, 2022, 2021, and 2020. Interest income is included in other income (expense), net on the Company's consolidated income statements. Unrealized losses on investments held for a period greater than 12 months at September 30, 2022 and September 30, 2021 were not material. The Company invests in debt securities that are rated investment grade. The Company reviews the individual debt securities in its portfolio to determine whether a credit loss exists by comparing the extent to which the fair value is less than the amortized cost and considering any changes to ratings of a debt security by a ratings agency. The Company determined that as of September 30, 2022, there were no credit losses on any investments within its portfolio. Assets Measured and Recorded at Fair Value on a Non-Recurring Basis The Company’s non-financial assets and liabilities, which include goodwill, intangible assets, and long-lived assets, are not required to be carried at fair value on a recurring basis. These non-financial assets and liabilities are measured at fair value on a non-recurring basis when there is an indicator of impairment, and they are recorded at fair value only when impairment is recognized. The Company reviews goodwill for impairment annually, during the second quarter of each fiscal year, or as circumstances indicate the possibility of impairment. The Company monitors the carrying value of tangible and intangible long-lived assets for impairment whenever events or changes in circumstances indicate its carrying amount may not be recoverable. As a result of a planned change in the use of the asset, the Company recorded an impairment of $6.2 million against the Shape trade name intangible asset, which was reflected in the Sales and Marketing line item on the Company's consolidated income statement for the year ended September 30, 2022. The Company did not recognize any impairment charges related to its intangible assets for the years ended September 30, 2021 and 2020. There were no long-lived asset impairment charges for the year ended September 30, 2022. During the year ended September 30, 2021, the Company recorded an impairment of $23.5 million against the operating lease right-of-use asset related to the permanent exit of six floors in its corporate headquarters and $10.3 million for tenant improvements and other fixed assets associated with the exited floors. The Company also recorded an impairment of $6.7 million against the operating lease right-of-use asset related to the integration of the former Shape headquarters in Santa Clara, California and $0.2 million for other fixed assets associated with the impaired Shape headquarters. During the year ended September 30, 2020, the Company recorded impairment of a right-of-use asset of $9.7 million related to the former Seattle headquarters location, due to the low likelihood of future sublease receipts, as the Company will no longer seek to sublease the space. The Company calculated the fair value of the right-of-use assets, tenant improvements and other fixed assets based on estimated future discounted cash flows and classified the fair value as a Level 3 measurement due to the significance of unobservable inputs, which included the amount and timing of estimated sublease rental receipts that the Company could reasonably obtain over the remaining lease term and the discount rate. The impairment charges for the years ended September 30, 2021 and 2020 were allocated to various expense line items on the Company’s consolidated income statements based on the teams that previously worked out of the exited space. Impairment charges were allocated to the following income statement line items for the years ended September 30, 2022, 2021, and 2020 (in thousands): Years Ended September 30, 2022 2021 2020 Cost of net product revenue $ — $ 2,865 $ 241 Cost of net service revenue — 3,492 1,034 Sales and marketing 6,175 11,515 2,876 Research and development — 12,974 2,906 General and administrative — 9,852 2,616 Total impairment charges $ 6,175 $ 40,698 $ 9,673 During the years ended September 30, 2022, 2021, and 2020, the Company did not recognize any impairment charges related to goodwill.

Balance Sheet Details

Balance Sheet Details	12 Months Ended
	Sep. 30, 2022
Balance Sheet Details [Abstract]
Balance Sheet Details	Balance Sheet Details Cash, Cash Equivalents and Restricted Cash The following table provides a reconciliation of the Company’s cash and cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total cash, cash equivalents and restricted cash shown in the Company’s consolidated statements of cash flows for the periods presented (in thousands): September 30, 2022 2021 Cash and cash equivalents $ 758,012 $ 580,977 Restricted cash included in other assets, net 4,195 3,356 Total cash, cash equivalents and restricted cash $ 762,207 $ 584,333 Inventories Inventories consist of the following (in thousands): September 30, 2022 2021 Finished goods $ 10,164 $ 13,081 Raw materials 58,201 8,974 $ 68,365 $ 22,055 Other Current Assets Other current assets consist of the following (in thousands): September 30, 2022 2021 Unbilled receivables $ 319,707 $ 215,396 Prepaid expenses 57,340 59,636 Capitalized contract acquisition costs 34,658 34,265 Other 1 77,609 28,605 $ 489,314 $ 337,902 (1) As of September 30, 2022, includes a deposit of $57.0 million used to support the working capital needs of the Company’s primary contract manufacturer's procurement of components used in the manufacturing of system hardware. Property and Equipment Property and equipment consist of the following (in thousands): September 30, 2022 2021 Computer equipment $ 168,204 $ 166,846 Software 86,036 94,169 Office furniture and equipment 41,619 45,204 Leasehold improvements 173,689 174,504 469,548 480,723 Accumulated depreciation and amortization (301,366) (289,559) $ 168,182 $ 191,164 Depreciation and amortization expense totaled approximately $56.0 million, $61.3 million, and $59.5 million for the fiscal years ended September 30, 2022, 2021 and 2020, respectively. There were no long-lived asset impairment charges for the year ended September 30, 2022. During the year ended September 30, 2021, the Company recorded an impairment of $10.3 million for leasehold improvements and other fixed assets associated with the permanent exit of six floors in its corporate headquarters. The Company also recorded an impairment of $0.2 million for fixed assets associated with the integration of the former Shape headquarters in Santa Clara, California. The impairment charges for the year ended September 30, 2021 were allocated to various expense line items on the Company’s consolidated income statements based on the teams that previously worked out of the exited space. Goodwill Changes in the carrying amount of goodwill during fiscal years 2022 and 2021 are summarized as follows (in thousands): Balance, September 30, 2020 $ 1,858,966 Acquisition of Volterra, Inc. 351,417 Other 6,170 Balance, September 30, 2021 2,216,553 Acquisition of Threat Stack, Inc. 43,956 Other (1,227) Balance, September 30, 2022 $ 2,259,282 Other Assets Other assets consist of the following (in thousands): September 30, 2022 2021 Intangible assets $ 200,288 $ 237,178 Unbilled receivables 224,780 158,885 Capitalized contract acquisition costs 42,561 43,571 Other 48,493 32,924 $ 516,122 $ 472,558 Intangible assets are included in other assets on the consolidated balance sheets and consist of the following (in thousands): September 30, 2022 September 30, 2021 Gross Accumulated Net Carrying Gross Accumulated Net Carrying Developed technology $ 319,436 $ (151,332) $ 168,104 $ 305,673 $ (111,279) $ 194,394 Customer relationships 46,142 (25,630) 20,512 41,742 (17,865) 23,877 Patents and trademarks 23,504 (19,255) 4,249 20,260 (17,180) 3,080 Trade names 24,973 (17,550) 7,423 24,973 (9,146) 15,827 Non-compete covenants 2,260 (2,260) — 2,260 (2,260) — $ 416,315 $ (216,027) $ 200,288 $ 394,908 $ (157,730) $ 237,178 Amortization expense related to intangible assets was approximately $36.4 million, $48.7 million, and $34.6 million for the fiscal years ended September 30, 2022, 2021 and 2020, respectively. For intangible assets held as of September 30, 2022, amortization expense for the five succeeding fiscal years is as follows (in thousands): 2023 $ 51,303 2024 46,030 2025 41,559 2026 36,805 2027 15,526 $ 191,223 Accrued Liabilities Accrued liabilities consist of the following (in thousands): September 30, 2022 2021 Payroll and benefits $ 165,437 $ 179,147 Operating lease liabilities, current 42,523 49,286 Income and other tax accruals 41,217 44,075 Other 60,642 68,979 $ 309,819 $ 341,487 Other Long-term Liabilities Other long-term liabilities consist of the following (in thousands): September 30, 2022 2021 Income taxes payable $ 59,553 $ 66,081 Other 8,157 9,155 $ 67,710 $ 75,236

Debt Facilities

Debt Facilities	12 Months Ended
	Sep. 30, 2022
Debt Disclosure [Abstract]
Debt Facilities	Debt Facilities Term Credit Agreement In connection with the acquisition of Shape, on January 24, 2020, the Company entered into a Term Credit Agreement ("Term Credit Agreement") with certain institutional lenders that provides for a senior unsecured term loan facility in an aggregate principal amount of $400.0 million (the "Term Loan Facility"). The proceeds from the Term Loan Facility were primarily used to finance the acquisition of Shape and related expenses. In connection with the Term Loan Facility, the Company incurred $2.2 million in debt issuance costs, which are recorded as a reduction to the carrying value of the principal amount of the debt. Borrowings under the Term Loan Facility bear interest at a rate equal to, at the Company's option, (a) LIBOR, adjusted for customary statutory reserves, plus an applicable margin of 1.125% to 1.75% depending on the Company's leverage ratio, or (b) an alternate base rate determined in accordance with the Term Credit Agreement, plus an applicable margin of 0.125% to 0.750% depending on the Company's leverage ratio. Interest on the outstanding principal of borrowings is currently due quarterly in arrears. As of September 30, 2022, the margin for LIBOR-based loans was 1.125% and the margin for alternate base rate loans was 0.125%. The Term Loan Facility matures on January 24, 2023 with quarterly installments (commencing with the first full fiscal quarter ended after January 24, 2020) equal to 1.25% of the original principal amount of the Term Loan Facility. The remaining outstanding principal of borrowings under the Term Loan Facility is due upon maturity on January 24, 2023. Borrowings under the Term Loan Facility may be voluntarily prepaid, in whole or in part, without penalty or premium. Borrowings repaid or prepaid under the Term Loan Facility may not be reborrowed. Among certain affirmative and negative covenants provided in the Term Credit Agreement, there is a financial covenant that requires the Company to maintain a leverage ratio, calculated as of the last day of each fiscal quarter, of consolidated total indebtedness to consolidated EBITDA. This covenant may result in a higher interest rate on its outstanding principal borrowings on the Term Loan Facility in future periods, depending on the Company's performance. As of September 30, 2022, the Company was in compliance with all covenants. As of September 30, 2022, $350.0 million of principal amount under the Term Loan Facility was outstanding, excluding unamortized debt issuance costs of $0.2 million. The outstanding principal amount was included in current liabilities on the Company's consolidated balance sheet as of September 30, 2022. The weighted average interest rate on the principal amount under the Term Loan Facility outstanding balance was 2.190%, 1.361%, and 2.365% for the fiscal years ended September 30, 2022, 2021, and 2020, respectively. The following table presents the scheduled principal maturities as of September 30, 2022 (in thousands): Fiscal Years Ending September 30: 2023 $ 350,000 Total $ 350,000 Revolving Credit Agreement On January 31, 2020, the Company entered into a Revolving Credit Agreement (the "Revolving Credit Agreement") that provides for a senior unsecured revolving credit facility in an aggregate principal amount of $350.0 million (the "Revolving Credit Facility"). The Company has the option to increase commitments under the Revolving Credit Facility from time to time, subject to certain conditions, by up to $150.0 million. Borrowings under the Revolving Credit Facility bear interest at a rate equal to, at the Company's option, (a) LIBOR, adjusted for customary statutory reserves, plus an applicable margin of 1.125% to 1.75% depending on the Company's leverage ratio, or (b) an alternate base rate determined in accordance with the Revolving Credit Agreement, plus an applicable margin of 0.125% to 0.750% depending on the Company's leverage ratio. The Revolving Credit Agreement also requires payment of a commitment fee calculated at a rate per annum of 0.125% to 0.300% depending on the Company's leverage ratio on the undrawn portion of the Revolving Credit Facility. Commitment fees incurred during fiscal year 2022 were not material.

Leases

Leases	12 Months Ended
	Sep. 30, 2022
Leases [Abstract]
Leases	Leases The majority of the Company's operating lease payments relate to its corporate headquarters in Seattle, Washington, which includes approximately 515,000 square feet of office space. The lease commenced in April 2019 and expires in 2033 with an option for renewal. The Company also leases additional office and lab space for product development and sales and support personnel in the United States and internationally. The Company's lease agreements do not contain any material residual value guarantees or material restrictive covenants. The components of the Company's operating lease expenses for the years ended September 30, 2022, 2021, and 2020 were as follows (in thousands): Fiscal year ended September 30, 2022 2021 2020 Operating lease expense $ 47,302 $ 47,993 $ 49,925 Short-term lease expense 2,465 2,953 3,563 Variable lease expense 23,209 25,200 21,980 Total lease expense $ 72,976 $ 76,146 $ 75,468 Variable lease expense primarily consists of common area maintenance and parking expenses. Supplemental balance sheet information related to the Company's operating leases was as follows (in thousands, except lease term and discount rate): September 30, 2022 2021 Operating lease right-of-use assets, net $ 227,475 $ 244,934 Operating lease liabilities, current 1 42,523 49,286 Operating lease liabilities, long-term 272,376 296,945 Total operating lease liabilities $ 314,899 $ 346,231 Weighted average remaining lease term (in years) 9.2 9.7 Weighted average discount rate 2.66 % 2.60 % (1) Current portion of operating lease liabilities is included in accrued liabilities on the Company's consolidated balance sheets. As of September 30, 2022, the future operating leases payments for each of the next five years and thereafter is as follows (in thousands): Fiscal Years Ending September 30: Operating Lease 2023 $ 50,427 2024 46,288 2025 38,793 2026 29,241 2027 28,592 Thereafter 166,585 Total lease payments 359,926 Less: imputed interest (45,027) Total lease liabilities $ 314,899 Operating lease liabilities above do not include sublease income. As of September 30, 2022, the Company expects to receive sublease income of approximately $21.6 million, which consists of $7.5 million to be received in fiscal year 2023 and $14.1 million to be received over the three fiscal years thereafter. There were no impairments against right-of-use assets for the year ended September 30, 2022. During the year ended September 30, 2021, the Company recorded an impairment of $23.5 million against the operating lease right-of-use asset related to the exit of six floors in its corporate headquarters. The Company also recorded an impairment of $6.7 million against the right-of-use asset related to the integration of the former Shape headquarters in Santa Clara, California. During the year ended September 30, 2020, the Company recorded an impairment for $9.7 million against the right-of-use asset related to the former Seattle headquarters location, due to the low likelihood of future sublease receipts, as the Company will no longer seek to sublease the space. As of September 30, 2022, the Company had no significant operating leases that were executed but not yet commenced.

Income Taxes

Income Taxes	12 Months Ended
	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The United States and international components of income before income taxes are as follows (in thousands): Years Ended September 30, 2022 2021 2020 United States $ 217,323 $ 189,398 $ 216,409 International 168,070 197,539 179,988 $ 385,393 $ 386,937 $ 396,397 The provision for income taxes consists of the following (in thousands): Years Ended September 30, 2022 2021 2020 Current U.S. federal $ 35,259 $ 53,107 $ 26,978 State 14,592 16,686 4,230 Foreign 54,079 62,832 50,368 Total 103,930 132,625 81,576 Deferred U.S. federal (28,721) (61,739) 10,875 State (11,332) (15,294) (1,121) Foreign (644) 104 (2,374) Total (40,697) (76,929) 7,380 $ 63,233 $ 55,696 $ 88,956 The effective tax rate differs from the U.S. federal statutory rate as follows (in thousands): Years Ended September 30, 2022 2021 2020 Income tax provision at statutory rate $ 80,933 $ 81,257 $ 83,243 State taxes, net of federal benefit 6,012 5,118 4,258 Tax impact of foreign operations (21,435) (26,881) (7,693) Research and development and other credits (18,917) (18,055) (11,843) Stock-based and other compensation 15,070 12,740 18,002 Other 1,570 1,517 2,989 $ 63,233 $ 55,696 $ 88,956 The Company does not maintain an indefinite reinvestment assertion on unremitted foreign earnings and has recorded a deferred tax liability for any estimated foreign, federal, or state tax liabilities associated with a future repatriation of foreign earnings. The Company benefits from tax incentive arrangements in certain foreign jurisdictions, one of which expired in fiscal year 2021 and the rest of which expire in fiscal years 2026 to 2034. The tax incentive agreements are conditional upon meeting certain operational, employment, and investment requirements. These arrangements decreased foreign taxes by $8.5 million, $6.0 million and $8.2 million, and increased diluted earnings per common share by $0.14, $0.10 and $0.13 for the years ended September 30, 2022, 2021 and 2020, respectively. The tax effects of the temporary differences that give rise to the deferred tax assets and liabilities are as follows (in thousands): Years Ended September 30, 2022 2021 Deferred tax assets Net operating loss carry-forwards $ 42,849 $ 41,252 Capitalized research and development costs 158,206 95,259 Accrued compensation and benefits 14,068 13,207 Stock-based compensation 10,389 12,829 Deferred revenue 32,244 30,115 Lease liabilities 21,572 23,747 Other accruals and reserves 18,797 18,450 Tax credit carryforwards 28,858 34,187 Depreciation 505 580 327,488 269,626 Valuation allowance (46,136) (40,404) 281,352 229,222 Deferred tax liabilities Purchased intangibles (57,350) (57,219) Depreciation (22,278) (26,516) Deferred costs (12,987) (13,057) Other accruals and reserves (8,153) (6,651) (100,768) (103,443) Net deferred tax assets $ 180,584 $ 125,779 At September 30, 2022, the Company had foreign net operating loss carryforwards of approximately $63.4 million that can be carried forward indefinitely, and $0.3 million that will expire in fiscal years 2028 to 2039. The Company had $85.3 million of federal net operating loss carryforwards, of which $52.0 million can be carried forward indefinitely and $33.3 million that will expire in fiscal years 2033 to 2038. The annual utilization of the federal net operating loss carryforwards is limited under Internal Revenue Code Section 382. The Company also had $448.4 million of state net operating loss carryforwards, of which $253.1 million can be carried forward indefinitely and $195.3 million will expire in fiscal years 2029 to 2042. In addition, there are $3.1 million of foreign credit carryforwards that will expire in fiscal years 2023 to 2038, $7.8 million of federal credit carryforwards that will expire in fiscal years 2033 to 2041, $29.5 million of state tax credit carryforwards that can be carried forward indefinitely, and $3.9 million of state tax credit carryforwards that will expire in fiscal years 2031 to 2037. Management believes that it is more likely than not that the benefit from certain foreign net operating loss and credit carryforwards and state tax net operating loss and credit carryforwards will not be realized. In recognition of this risk, the Company has provided a valuation allowance on the deferred tax assets relating to these carryforwards. The net change in the total valuation allowance was an increase of $5.7 million and $7.8 million for years ended September 30, 2022 and 2021, respectively. The Company recognizes the financial statement impact of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more-likely-than-not threshold, the amount recognized in the financial statements is the largest impact that has a greater than fifty percent likelihood of being realized upon ultimate settlement with the relevant tax authority. The following table provides a reconciliation of the beginning and ending amount of unrecognized tax benefits in fiscal years 2022, 2021 and 2020 (in thousands): 2022 2021 2020 Balance, beginning of period $ 70,814 $ 51,767 $ 42,287 Gross increases related to prior period tax positions 4,816 14,867 8,664 Gross decreases related to prior period tax positions (10,538) — (1,051) Gross increases related to current period tax positions 10,203 12,595 9,272 Decreases relating to settlements with tax authorities — (321) (3,578) Reductions due to lapses of statute of limitations (8,455) (8,094) (3,827) Balance, end of period $ 66,840 $ 70,814 $ 51,767 The total amount of gross unrecognized tax benefits was $66.8 million, $70.8 million, and $51.8 million as of September 30, 2022, 2021, and 2020, respectively, of which, $43.2 million, $39.2 million, and $34.3 million, if recognized, would affect the effective tax rate. There is a reasonable possibility that the Company’s unrecognized tax benefits will change within twelve months due to audit settlements or the expiration of statute of limitations, but the Company does not expect the change to be material to the consolidated financial statements. The Company recognizes interest and, if applicable, penalties (not included in the “unrecognized tax benefits” table above) for any uncertain tax positions. Interest and penalties are recorded as a component of income tax expense. In the years ended September 30, 2022, 2021 and 2020, the Company recorded approximately a $1.5 million decrease, $1.4 million increase and $1.0 million decrease, respectively, of interest and penalty expense related to uncertain tax positions. As of September 30, 2022 and 2021, the Company had a cumulative balance of accrued interest and penalties on unrecognized tax positions of $2.9 million and $4.4 million, respectively. The Company and its subsidiaries are subject to U.S. federal income tax as well as the income tax of multiple state and foreign jurisdictions. The Company has concluded all U.S. federal income tax matters for fiscal years through September 30, 2018. Major jurisdictions where there are wholly owned subsidiaries of F5, Inc. which require income tax filings include the United Kingdom, Singapore, Israel, and India. The earliest periods open for review by local taxing authorities are fiscal years 2020 for the United Kingdom, 2017 for Singapore, 2013 for Israel, and 2019 for India. The Company is currently under audit by various states for fiscal years 2016 through 2021, and by various foreign jurisdictions including Germany for fiscal years 2016 to 2019, India for fiscal years 2019 to 2020, Israel for fiscal years 2013 to 2017, and Saudi Arabia for fiscal years 2015 to 2020. Within the next four fiscal quarters, the statute of limitations will otherwise begin to close on the fiscal year 2019 federal income tax return, fiscal years 2018 and 2019 state income tax returns, and fiscal years 2015 to 2021 foreign income tax returns.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Sep. 30, 2022
Equity [Abstract]
Stockholders' Equity	Shareholders' Equity Common Stock Repurchase On July 25, 2022, the Company announced that its Board of Directors authorized an additional $1.0 billion for its common stock share repurchase program. This authorization is incremental to the existing $5.4 billion program, initially approved in October 2010 and expanded in subsequent fiscal years. Acquisitions for the share repurchase programs will be made from time to time in private transactions, accelerated share repurchase programs, or open market purchases as permitted by securities laws and other legal requirements. The programs can be terminated at any time. On February 3, 2021, the Company entered into Accelerated Share Repurchase (ASR) agreements with two financial institutions under which the Company paid an aggregate of $500 million. The ASR agreements were accounted for as two separate transactions (1) a repurchase of common stock and (2) an equity-linked contract on the Company's own stock. Upon execution of the ASR agreements, the Company received an initial delivery of 2.1 million shares for an aggregate price of $400 million, based on the market price of $194.91 per share of the Company's common stock on the date of the transaction. The initial shares received by the Company were retired immediately upon receipt. The equity-linked contract for the remaining $100 million, representing remaining shares to be delivered by the financial institutions under the ASR agreements, was recorded to common stock as of March 31, 2021 and was settled in the third quarter of fiscal 2021 with the Company receiving 449,049 additional shares, which were retired immediately upon receipt. The total ASR resulted in a repurchase of 2.5 million shares of the Company's common stock at a volume weighted average repurchase price, less an agreed upon discount, of $199.90 per share. The shares received by the Company were retired, accounted for as a reduction to stockholder’s equity in the consolidated balance sheets, and treated as a repurchase of common stock for purposes of calculating earnings per share. The Company was not required to make any additional cash payments or delivery of common stock to the financial institutions upon settlement of the agreements. The following table summarizes the Company's repurchases and retirements of its common stock under its Stock Repurchase Program, including the ASR (in thousands, except per share data): Years Ended September 30, 2022 2021 2020 Shares repurchased 2,611 2,501 799 Average price per share $ 191.47 $ 199.90 $ 125.10 Amount repurchased $ 500,023 $ 500,000 $ 100,016 As of September 30, 2022, the Company had $1,272 million remaining authorized to purchase shares under its share repurchase program.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Sep. 30, 2022
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Stock-Based Compensation	Stock-based Compensation The Company recognized $249.2 million, $243.3 million and $201.9 million of stock-based compensation expense for the fiscal years ended September 30, 2022, 2021 and 2020, respectively. The income tax benefit recognized on stock-based compensation within income tax expense was $47.3 million, $44.1 million and $37.6 million for the fiscal years ended September 30, 2022, 2021 and 2020, respectively. As of September 30, 2022, there was $196.5 million of total unrecognized stock-based compensation cost, the majority of which will be recognized over approximately two years. Going forward, stock-based compensation expenses may increase as the Company issues additional equity-based awards to continue to attract and retain key employees. On October 31, 2022, the Company’s Board of Directors and Talent and Compensation Committee approved 1,321,304 RSUs to employees and executive officers pursuant to the Company’s annual equity awards program. Company has adopted a number of stock-based compensation plans as discussed below. 2011 Employee Stock Purchase Plan. In April 2012, the Board of Directors amended and restated the Company’s 1999 Employee Stock Purchase Plan, or the Employee Stock Purchase Plan. A total of 10,000,000 shares of common stock have been reserved for issuance under the Employee Stock Purchase Plan. The Employee Stock Purchase Plan permits eligible employees to acquire shares of the Company’s common stock through periodic payroll deductions of up to 15% of base compensation. No employee may purchase more than 10,000 shares during an offering period. In addition, no employee may purchase more than $25,000 worth of stock, determined by the fair market value of the shares at the time such option is granted, in one calendar year. The Employee Stock Purchase Plan has been implemented in a series of offering periods, each 6 months in duration. The price at which the common stock may be purchased is 85% of the lesser of the fair market value of the Company’s common stock on the first day of the applicable offering period or on the last day of the respective purchase period. As of September 30, 2022 there were 945,136 shares available for awards under the Employee Stock Purchase Plan. In determining the fair value of the right to purchase under the Employee Stock Purchase Plan, the Company uses the Black-Scholes option pricing model that employs the following key assumptions: Employee Stock Purchase Plan 2022 2021 2020 Risk-free interest rate 0.05% - 0.62% 0.07% - 0.13% 1.10% - 1.97% Expected dividend — — — Expected term 0.5 years 0.5 years 0.5 years Expected volatility 26.34% - 31.57% 29.67% - 37.22% 26.32% - 41.94% Acquisition Related Incentive Plans. In May 2019, the Company adopted the Nginx Acquisition Equity Incentive Plan, or the Nginx Acquisition Plan. The Nginx Acquisition Plan provided for discretionary grants of stock options and stock units for employees, directors and consultants of Nginx, Inc. to whom the Company offered employment in connection with the Company’s acquisition of Nginx. A total of 183,061 shares of common stock were reserved for issuance under the Nginx Acquisition Plan. Upon certain changes in control of the Company, the surviving entity will either assume or substitute all outstanding stock awards under the Nginx Acquisition Plan or the vesting of 50% of the stock awards shall be accelerated. During the fiscal year 2022, the Company issued no stock options or restricted stock units under the Nginx Acquisition Plan. As of September 30, 2022, there were no options outstanding and 20,923 stock units outstanding. The Company terminated the Nginx Acquisition Plan effective October 31, 2019 and no additional shares may be issued from the Nginx Acquisition Plan. In connection with the Company’s acquisition of Nginx, Inc. in the third quarter of fiscal year 2019, the Company assumed the Nginx Inc. 2011 Share Plan, or the Nginx Plan. Unvested options to acquire Nginx's common stock and unvested stock units with respect to Nginx’s common stock were converted into options to acquire the Company’s common stock and stock units with respect to the Company’s stock in connection with the acquisition. A total of 302,634 shares of common stock were reserved for issuance under the Nginx Plan (including converted options and stock units). The Nginx Plan provided for grants of stock options, stock awards and stock units to persons who were employees, officers, directors and consultants to Nginx, Inc. prior to May 8, 2019. During the fiscal year 2022, the Company issued no stock options or restricted stock units under the Nginx Plan. As of September 30, 2022, there were options to purchase 16,295 shares outstanding and 2,997 stock units outstanding. The Company terminated the Nginx Plan effective October 31, 2019 and no additional shares may be issued from the Nginx Plan. In January 2020, the Company adopted the Shape Acquisition Equity Incentive Plan, or the Shape Acquisition Plan. The Shape Acquisition Plan provided for discretionary grants of stock options and stock units for employees, directors and consultants of Shape Security, Inc. to whom the Company offered employment in connection with the Company’s acquisition of Shape. A total of 450,000 shares of common stock were reserved for issuance under the Shape Acquisition Plan. Upon certain changes in control of the Company, the surviving entity will either assume or substitute all outstanding stock awards under the Shape Acquisition Plan or the vesting of 50% of the stock awards shall be accelerated. During the fiscal year 2022, the Company issued no stock options or restricted stock units under the Shape Acquisition Plan. As of September 30, 2022, there were no options outstanding and 83,164 stock units outstanding. The Company terminated the Shape Acquisition Plan effective December 28, 2020 and no additional shares may be issued from the Shape Acquisition Plan. In connection with the Company’s acquisition of Shape Security, Inc. in the second quarter of fiscal year 2020, the Company assumed the Shape 2011 Stock Plan, or the Shape Plan. Unvested options to acquire Shape’s common stock and unvested stock units with respect to Shape’s common stock were converted into options to acquire the Company’s common stock and stock units with respect to the Company’s stock in connection with the acquisition. A total of 501,085 shares of common stock were reserved for issuance under the Shape Plan (including converted options and stock units). The Shape Plan provided for grants of stock options, stock awards and stock units to persons who were employees, officers, directors and consultants to Shape Security, Inc. prior to January 24, 2020. During the fiscal year 2022, the Company issued no stock options or restricted stock units under the Shape Plan. As of September 30, 2022, there were options to purchase 79,508 shares outstanding and 1,443 stock units outstanding. The Company terminated the Shape Plan effective December 28, 2020 and no additional shares may be issued from the Shape Plan. In January 2021, the Company adopted the Volterra Acquisition Equity Incentive Plan, or the Volterra Acquisition Plan. The Volterra Acquisition Plan provided for discretionary grants of stock options and stock units for employees, directors and consultants of Volterra, Inc. to whom the Company offered employment in connection with the Company’s acquisition of Volterra. A total of 140,000 shares of common stock were reserved for issuance under the Volterra Acquisition Plan. Upon certain changes in control of the Company, the surviving entity will either assume or substitute all outstanding stock awards under the Volterra Acquisition Plan or the vesting of 50% of the stock awards shall be accelerated. During the fiscal year 2022, the Company issued no stock options or restricted stock units under the Volterra Acquisition Plan. As of September 30, 2022, there were no options outstanding and 103,880 stock units outstanding. The Company terminated the Volterra Acquisition Plan effective October 29, 2021 and no additional shares may be issued from the Volterra Acquisition Plan. In connection with the Company’s acquisition of Volterra, Inc. in the second quarter of fiscal year 2021, the Company assumed the Volterra 2017 Stock Plan, or the Volterra Plan. Unvested options to acquire Volterra’s common stock and unvested stock units with respect to Volterra’s common stock were converted into options to acquire the Company’s common stock and stock units with respect to the Company’s stock in connection with the acquisition. A total of 261,696 shares of common stock were reserved for issuance under the Volterra Plan (including converted options and stock units). The Volterra Plan provided for grants of stock options, stock awards and stock units to persons who were employees, officers, directors and consultants to Volterra, Inc. prior to January 22, 2021. During the fiscal year 2022, the Company issued no stock options or restricted stock units under the Volterra Plan. As of September 30, 2022, there were options to purchase 68,993 shares outstanding and 17,934 stock units outstanding. The Company terminated the Volterra Plan effective October 29, 2021 and no additional shares may be issued from the Volterra Plan. In November 2021, the Company adopted the Threat Stack Acquisition Equity Incentive Plan, or the Threat Stack Acquisition Plan. The Threat Stack Acquisition Plan provided for discretionary grants of stock options and stock units for employees, directors and consultants of Threat Stack to whom the Company offered employment in connection with the Company’s acquisition of Threat Stack. A total of 35,000 shares of common stock were reserved for issuance under the Threat Stack Acquisition Plan. Upon certain changes in control of the Company, the surviving entity will either assume or substitute all outstanding stock awards under the Threat Stack Acquisition Plan or the vesting of 50% of the stock awards shall be accelerated. During the fiscal year 2022, the Company issued 25,838 stock units under the Threat Stack Acquisition Plan. As of September 30, 2022, there were 23,534 stock units outstanding. F5, Inc. Incentive Plan. In March 2022, the Company adopted the F5, Inc. Incentive Plan, or the Plan, which amended and restated the 2014 Incentive Plan. The Plan provides for discretionary grants of stock options, stock units and other equity and cash-based awards for employees, including officers, directors and consultants. A total of 23,380,000 shares of common stock have been reserved for issuance under the Plan. Upon certain changes in control of the Company, all outstanding and unvested options or stock awards under the Plan will vest at the rate of 50%, unless assumed or substituted by the acquiring entity. During the fiscal year 2022, the Company issued no stock options, 111,283 performance stock units and 1,118,854 restricted stock units under the Plan. As of September 30, 2022, there were no options outstanding, 208,116 performance stock units outstanding, 1,137,619 restricted stock units outstanding and 2,072,778 shares available for new awards under the Plan. A summary of restricted stock unit activity under the Plan is as follows: Performance Stock Units Restricted Stock Units Outstanding Weighted Outstanding Weighted Balance, September 30, 2021 230,926 $ 136.47 1,340,548 $ 141.90 Units granted 111,283 200.74 1,118,854 206.45 Units vested (119,889) 215.12 (1,122,583) 188.04 Units cancelled (14,204) 151.07 (199,200) 170.35 Balance, September 30, 2022 208,116 $ 169.99 1,137,619 $ 184.59 A majority of the restricted stock units the Company grants to its employees vest quarterly over a two Expected Volatility Fair Value Expected Term Risk-Free Index Expected Grant Date per Share (in years) Interest Rate F5 Members Dividend November 1, 2021 Tranche 1 $ 283.35 0.91 0.13 % 26.21 % 27.27 % — Tranche 2 $ 302.53 1.91 0.47 % 35.13 % 42.87 % — Tranche 3 $ 308.76 2.91 0.76 % 32.54 % 38.24 % — As of September 30, 2022, the following annual equity grants for executive officers or a portion thereof are outstanding: Grant Date RSUs Granted Vesting Schedule Vesting Period Date Fully Vested November 1, 2021 160,384 Quarterly, Annually 1,2 3 years November 1, 2024 November 2, 2020 257,568 Quarterly, Annually 1 3 years November 1, 2023 November 1, 2019 228,616 Quarterly, Annually 1 3 years November 1, 2022 November 1, 2018 144,066 Quarterly, Annually 1 3 years November 1, 2021 (1) 50% of the annual equity grant vests in equal quarterly increments and 50% is subject to the Company achieving specified annual performance goals. (2) For the Company's Chief Executive Officer, 40% of the annual equity grant vests in equal quarterly increments and 60% is subject to the Company achieving specified annual performance goals. A summary of stock option activity under all of the Company’s plans is as follows: Options Outstanding Number of Weighted Balance, September 30, 2021 324,624 $ 30.83 Options granted — — Options exercised (143,128) 25.24 Options cancelled (16,700) 53.98 Balance, September 30, 2022 164,796 $ 33.34 There were no stock options granted in fiscal year 2022. All stock options granted in fiscal years 2021 and 2020 were replacement awards of those assumed as part of the acquisitions of Volterra and Shape, respectively. The total intrinsic value of options exercised during fiscal 2022, 2021 and 2020 was $25.6 million, $25.6 million and $11.4 million, respectively. A summary of options outstanding that are exercisable and that have vested and are expected to vest as of September 30, 2022 is as follows: Number of Weighted Weighted Aggregate (In thousands) Stock options outstanding 164,796 6.45 $ 33.34 $ 18,357 Exercisable 127,072 6.20 $ 30.76 $ 14,482 Vested and expected to vest 162,713 6.42 $ 33.20 $ 18,147 (1) Aggregate intrinsic value represents the difference between the fair value of the Company’s common stock underlying these options at September 30, 2022 and the related exercise prices. As of September 30, 2022, equity based awards (including stock options and restricted stock units) are available for future issuance as follows: Awards Balance, September 30, 2021 1,988,410 Granted (1,255,975) Cancelled 327,201 Additional shares reserved (terminated), net 1,013,142 Balance, September 30, 2022 2,072,778

Net Income Per Share

Net Income Per Share	12 Months Ended
	Sep. 30, 2022
Net Income Per Share [Abstract]
Net Income Per Share	Net Income Per ShareBasic net income per share is computed by dividing net income by the weighted average number of common shares outstanding during the period. Diluted net income per share is computed by dividing net income by the weighted average number of common and dilutive common stock equivalent shares outstanding during the period. The Company’s nonvested restricted stock units do not have nonforfeitable rights to dividends or dividend equivalents and are not considered participating securities that should be included in the computation of earnings per share under the two-class method. The following table sets forth the computation of basic and diluted net income per share (in thousands, except per share data): Years Ended September 30, 2022 2021 2020 Numerator Net income $ 322,160 $ 331,241 $ 307,441 Denominator Weighted average shares outstanding — basic 60,274 60,707 60,911 Dilutive effect of common shares from stock options and restricted stock units 823 1,350 467 Weighted average shares outstanding — diluted 61,097 62,057 61,378 Basic net income per share $ 5.34 $ 5.46 $ 5.05 Diluted net income per share $ 5.27 $ 5.34 $ 5.01 Anti-dilutive stock-based awards excluded from the calculations of diluted earnings per share were not material for the years ended September 30, 2022, 2021 and 2020.

Commitments And Contingencies

Commitments And Contingencies	12 Months Ended
	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	Commitments and Contingencies Litigation Lynwood Investment CY Limited v. F5 Networks et al. On June 8, 2020, Lynwood Investment CY Limited (“Lynwood”) filed a lawsuit in the United States District Court for the Northern District of California against the Company and certain affiliates, along with other defendants. In its complaint, Lynwood claims to be the assignee of all rights and interests of Rambler Internet Holding LLC (“Rambler”), and alleges that the intellectual property in the NGINX software originally released by the co-founder of NGINX in 2004 belongs to Rambler (and therefore Lynwood, by assignment) because the software was created and developed while the co-founder was employed by Rambler. Lynwood asserts 26 causes of action against the various defendants, including copyright infringement, violation of trademark law, tortious interference, conspiracy, and fraud. The complaint seeks damages, disgorgement of profits, fees and costs, declarations of copyright and trademark ownership, trademark cancellations, and injunctive relief. Lynwood also initiated several trademark opposition and cancellation proceedings before the Trademark Trial and Appeal Board of the United States Patent and Trademark Office, which have all since been suspended. In August and October 2020, the Company and the other defendants filed motions to dismiss all claims asserted against them in the lawsuit. While these motions were pending, the Court ordered Lynwood to select ten of its twenty-six claims to litigate through trial while the remaining sixteen claims would be stayed pending resolution of the ten selected claims. On March 25 and 30, 2021, the Court dismissed the ten selected claims and granted Lynwood leave to cure the deficiencies in its complaint though it expressed doubt about Lynwood’s ability to do so. The Court further ruled that Lynwood may not add new causes of action or add new parties without stipulation or leave of court, and that unless Lynwood corrects “all the defects” identified in the Court’s orders and the Company’s and other defendants’ motions to dismiss, the Court will dismiss the ten claims with prejudice. On April 6, 2021, the Court referred the parties to private mediation to be completed by June 1, 2021. Pursuant to the Court’s order, the parties held a private mediation on May 27, 2021. The matter did not resolve. On April 29, 2021, Lynwood filed its amended complaint, seeking the same relief against the Company and other defendants. On May 27, 2021, the Company and other defendants filed a consolidated motion to dismiss the claims Lynwood had selected to proceed to litigate through trial, reserving their right to move to dismiss the 16 stayed claims once the Court lifts the stay. The motion to dismiss was set to be heard by the Court on October 14, 2021, but on October 11, 2021, the Court vacated the hearing and gave notice that it will decide the motion on the papers without oral argument. On August 16, 2022, the Court granted the consolidated motion to dismiss the claims Lynwood had selected to proceed to litigate through trial, without leave to amend the claims, thereby dismissing those claims with prejudice. On September 9, 2022, the parties stipulated to the dismissal of the remaining 16 stayed claims, with prejudice, and the Court entered a final judgment. On September 14, 2022, Lynwood filed a notice of appeal to the Ninth Circuit Court of appeals to appeal the Court’s dismissal of the claims Lynwood had selected to proceed to litigate through trial. Lynwood’s opening brief is currently due December 16, 2022 and the Company’s answer brief will be due January 17, 2023. Lynwood’s reply will be due February 7, 2023. In addition to the above matters, the Company is subject to a variety of legal proceedings, claims, investigations, and litigation arising in the ordinary course of business, including intellectual property litigation. Management believes that the Company has meritorious defenses to the allegations made in its pending cases and intends to vigorously defend these lawsuits; however, the Company is unable to currently determine if an unfavorable outcome is probable or estimate any potential amount or range of possible loss of these or similar matters. There are many uncertainties associated with any litigation and these actions or other third-party claims against the Company may cause it to incur costly litigation and/or substantial settlement charges that could have a material adverse effect on the Company's business, financial condition, results of operations, and cash flows. The Company records an accrual for loss contingencies for legal proceedings when it believes that an unfavorable outcome is both (a) probable and (b) the amount or range of any possible loss is reasonably estimable. The Company has not recorded any accrual for loss contingencies associated with such legal proceedings or the investigations discussed above.

Restructuring Charges

Restructuring Charges	12 Months Ended
	Sep. 30, 2022
Restructuring and Related Activities [Abstract]
Restructuring Charges	Restructuring ChargesIn the first quarter of fiscal 2022, the Company initiated a restructuring plan to match strategic and financial objectives and optimize resources for long term growth, including a reduction in force program affecting approximately 70 positions. The Company recorded a restructuring charge of $7.9 million in the first quarter of fiscal 2022. The Company does not expect to record any significant future charges related to the restructuring plan.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Sep. 30, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Employee Benefit Plans	Employee Benefit PlansThe Company has a 401(k) savings plan whereby eligible employees may voluntarily contribute a percentage of their compensation. The Company may, at its discretion, match a portion of the employees’ eligible contributions. Contributions by the Company to the plan during the years ended September 30, 2022, 2021, and 2020 were approximately $14.0 million, $13.2 million and $11.3 million, respectively. Contributions made by the Company vest over four years.

Segment Information

Segment Information	12 Months Ended
	Sep. 30, 2022
Segments, Geographical Areas [Abstract]
Segment Reporting Disclosure	Segment Information Operating segments are defined as components of an enterprise for which separate financial information is available and evaluated regularly by the chief operating decision-maker, or decision-making group, in deciding how to allocate resources and in assessing performance. Management has determined that the Company is organized as, and operates in, one reportable operating segment: the development, marketing and sale of application security and delivery solutions which enable its customers to develop, deploy, operate, secure, and govern applications in any architecture, from on-premises to the public cloud. Revenues by Geographic Location and Other Information The Company does business in three main geographic regions: the Americas (primarily the United States); Europe, the Middle East, and Africa (EMEA); and the Asia Pacific region (APAC). The Company’s chief operating decision-maker reviews financial information presented on a consolidated basis accompanied by information about revenues by geographic region. The Company’s foreign offices conduct sales, marketing and support activities. Revenues are attributed by geographic location based on the location of the customer. The following presents revenues by geographic region (in thousands): Years Ended September 30, 2022 2021 2020 Americas: United States $ 1,487,144 $ 1,365,625 $ 1,221,190 Other 85,711 92,111 95,878 Total Americas 1,572,855 1,457,736 1,317,068 EMEA 634,759 667,219 593,307 Asia Pacific 488,231 478,461 440,447 $ 2,695,845 $ 2,603,416 $ 2,350,822 The Company generates revenues from the sale of products and services. The Company continues to offer its products through a range of consumption models, from physical systems to software solutions and managed services. The following presents net product revenues by systems and software (in thousands): Years Ended September 30, 2022 2021 2020 Net product revenues Systems revenue $ 651,902 $ 748,192 $ 668,313 Software revenue 665,215 498,892 357,543 Total net product revenue $ 1,317,117 $ 1,247,084 $ 1,025,856 The following distributors of the Company's products accounted for more than 10% of total net revenue: Years Ended September 30, 2022 2021 2020 Ingram Micro, Inc. 20.0 % 19.2 % 16.7 % Synnex Corporation 13.4 % 11.1 % — The following distributors of the Company's products accounted for more than 10% of total receivables: September 30, 2022 2021 Ingram Micro, Inc. 12.9 % 12.6 % Synnex Corporation 12.6 % 11.9 % Carahsoft Technology 16.2 % 11.5 % The Company tracks assets by physical location. Long-lived assets consist of property and equipment, net, and are shown below (in thousands): September 30, 2022 2021 United States $ 134,699 $ 153,030 EMEA 17,376 20,526 Other countries 16,107 17,608 $ 168,182 $ 191,164

Subsequent Events

Subsequent Events	12 Months Ended
	Sep. 30, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn October 27, 2022, the Company entered into a four-year, non-cancelable Strategic Supply Agreement with one of the Company’s component suppliers. The agreement with the supplier provides committed delivery of components to the Company. The Company is obligated to purchase $10 million of component inventory annually, with a total commitment of $40 million within the four

Summary Of Significant Accoun_2

Summary Of Significant Accounting Policies (Policy)	12 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Accounting Principles	Accounting Principles The Company’s consolidated financial statements and accompanying notes are prepared on the accrual basis of accounting in accordance with generally accepted accounting principles in the United States of America (GAAP).
Principles Of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
Use Of Estimates and Assumptions	Use of Estimates and Assumptions The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Examples of estimates and assumptions include: revenue recognition, identifying and evaluating the performance obligations of contracts with non-standard terms, and the allocation of purchase consideration based on the relative fair value standalone sales price of these performance obligations; business combinations, including the determination of fair value for acquired developed technology assets and the evaluation and selection of significant assumptions such as revenue growth rate and technology migration curve; and the incremental borrowing rate for measuring lease obligations. Actual results may differ materially from management's estimates and assumptions.
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted CashThe Company considers all highly liquid investments with original maturities of three months or less to be cash equivalents. The Company invests its cash and cash equivalents in deposits with four major financial institutions, which, at times, exceed federally insured limits. The Company has not experienced any losses on its cash and cash equivalents. Amounts included in restricted cash represent those for which the Company's use is restricted by a contractual agreement.
Investments	Investments The Company classifies its debt investments as available-for-sale. Debt investments, consisting of certificates of deposit, corporate and municipal bonds and notes, the United States government and agency securities and international government securities are reported at fair value with the related unrealized gains and losses included as a component of accumulated other comprehensive income (loss) in shareholders’ equity. Realized gains and losses, credit allowances and impairments due to credit losses are included in other income (expense) in the Company’s consolidated income statements. Debt investments with maturities of less than one year or where management’s intent is to use the investments to fund current operations are classified as short-term investments. Debt investments with maturities of greater than one year are classified as long-term investments. As an approximation to fair value, equity investments are measured using net asset value (“NAV”) and are classified as long-term investments. Unrealized and realized gains and losses are recorded in other income (expense) in the Company's consolidated income statements.
Accounts Receivable	Accounts Receivable Trade accounts receivable are recorded at the invoiced amount, net of allowances for credit losses for any potential uncollectible amounts. The allowance for credit losses is based on the assessment of the collectability of accounts. Management regularly reviews the adequacy of the allowance for credit losses on a collective basis by considering the age of each outstanding invoice, each customer’s expected ability to pay and collection history, current market conditions, and reasonable and supportable forecasts of future economic conditions to determine whether the allowance is appropriate. Accounts receivable deemed uncollectible are charged against the allowance for credit losses when identified. For fiscal years ended September 30, 2022 and 2021, the allowance for credit losses was not material.
Unbilled Receivables	Unbilled Receivables Unbilled receivables represent amounts related to the Company's unconditional right to consideration associated with contracts with customers that have not yet been billed. Unbilled receivables are converted to accounts receivable at the point in time when the Company has the contractual right to invoice its customers. As of September 30, 2022, unbilled receivables that are expected to be reclassified to accounts receivable within the next 12 months are included in other current assets, with those expected to be transferred to accounts receivables in more than 12 months included in other assets.
Concentration Of Credit Risk	Concentration of Credit Risk The Company extends credit to customers and is therefore subject to credit risk. The Company performs initial and ongoing credit evaluations of its customers’ financial condition and does not require collateral. An allowance for credit losses is recorded for any potential uncollectible amount. Estimates are used in determining the allowance for credit losses in accordance with the Accounts Receivable policy. See Note 15 - Segment Information, for disaggregated accounts receivable by significant customer. The Company maintains its cash and investment balances with high credit quality financial institutions.
Fair Value Of Financial Instruments	Fair Value of Financial Instruments Short-term and long-term investments are recorded at fair value as the underlying securities are classified as available-for-sale with any unrealized gains or losses being recorded to other comprehensive income (or loss). The fair value for securities held is determined using quoted market prices, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency.
Inventories	Inventories The Company outsources the manufacturing of its pre-configured hardware platforms to contract manufacturers, who assemble each product to the Company’s specifications. As protection against component shortages and to provide replacement parts for its service teams, the Company also stocks limited supplies of certain key product components. The Company reduces inventory to net realizable value based on excess and obsolete inventories determined primarily by historical usage and forecasted demand. Inventories consist of hardware and related component parts and are recorded at the lower of cost and net realizable value (as determined by the first-in, first-out method).
Property And Equipment	Property and Equipment Property and equipment are stated at net book value. Depreciation of property and equipment is provided using the straight-line method over the estimated useful lives of the assets, ranging from two Property and equipment consist of the following (in thousands): September 30, 2022 2021 Computer equipment $ 168,204 $ 166,846 Software 86,036 94,169 Office furniture and equipment 41,619 45,204 Leasehold improvements 173,689 174,504 469,548 480,723 Accumulated depreciation and amortization (301,366) (289,559) $ 168,182 $ 191,164
Business Combinations	Business Combinations The Company’s business combinations are accounted for under the acquisition method. Management allocates the fair value of purchase consideration to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the acquisition date. The excess of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. Such valuations require management to make significant estimates and assumptions, especially with respect to intangible assets. On October 1, 2021, the Company completed its acquisition of Threat Stack, Inc. for a total purchase price of $68.9 million, of which $11.4 million of finite-lived developed technology was recorded.
Goodwill	Goodwill Goodwill represents the excess purchase price over the estimated fair value of net assets acquired as of the acquisition date. The Company tests goodwill for impairment on an annual basis and between annual tests when impairment indicators are identified, and goodwill is written down when impaired. For its annual goodwill impairment test in all periods to date, the Company has operated under one reporting unit and the fair value of its reporting unit has been determined by the Company’s enterprise value. The Company performs its annual goodwill impairment test during the second fiscal quarter. For its annual impairment test performed in the second quarter of fiscal 2022, the Company completed a quantitative assessment and determined that there was no impairment of goodwill. The Company also considered potential impairment indicators of goodwill at September 30, 2022 and noted no indicators of impairment.
Intangible Assets	Intangible AssetsIntangible assets with finite lives consist of acquired developed technology, customer relationships, patents and trademarks, trade names, and non-compete covenants acquired through business combinations or asset acquisitions. Intangible assets acquired through business combinations are recorded at their respective estimated fair values upon acquisition close. Other intangible assets acquired through asset acquisitions are recorded at their respective cost. The Company determines the estimated useful lives for acquired intangible assets based on the expected future cash flows associated with the respective asset. The Company's intangible assets with finite lives are amortized using the straight-line method over their estimated useful lives, ranging from two
Software Development Costs	Software Development Costs The authoritative guidance requires certain internal software development costs related to software to be sold to be capitalized upon the establishment of technological feasibility. Capitalized software development costs are amortized over the remaining estimated economic life of the product. The Company's software development costs incurred subsequent to achieving technological feasibility have not been significant and, as a result, all software development costs have been expensed as research and development activities as incurred.
Internal-Use Software	Internal-Use Software The Company capitalizes costs incurred during the application development stage associated with the development of internal-use software systems. The capitalized costs are then amortized over the estimated useful life of the software, which is generally three
Impairment Of Long-Lived Assets	Impairment of Long-Lived AssetsThe Company assesses the impairment of long-lived assets whenever events or changes in business circumstances indicate that the carrying amount of an asset may not be recoverable. When such events occur, management determines whether there has been impairment by comparing the anticipated undiscounted net future cash flows to the related asset’s carrying value. If impairment exists, the asset is written down to its estimated fair value.
Revenue Recognition	Revenue Recognition The Company sells products through distributors, resellers, and directly to end users. Revenue related to the Company's contracts with customers is recognized by following a five-step process: • Identify the contract(s) with a customer. Evidence of a contract generally consists of a purchase order issued pursuant to the terms and conditions of a distributor, reseller or end user agreement. • Identify the performance obligations in the contract. Performance obligations are identified in the Company's contracts and include hardware, hardware-based software, software-only solutions, cloud-based subscription services as well as a broad range of service performance obligations including consulting, training, installation and maintenance. • Determine the transaction price. The purchase price stated in an agreed upon purchase order is generally representative of the transaction price. The Company offers several programs in which customers are eligible for certain levels of rebates if certain conditions are met. When determining the transaction price, the Company considers the effects of any variable consideration. • Allocate the transaction price to the performance obligations in the contract. The transaction price in a contract is allocated based upon the relative standalone selling price of each distinct performance obligation identified in the contract. • Recognize revenue when (or as) the entity satisfies a performance obligation. The Company satisfies performance obligations either over time or at a point in time as discussed in further detail below. Revenue is recognized at the time the related performance obligation is satisfied by transferring control of promised products and services to a customer. Revenue is recognized net of any taxes collected, which are subsequently remitted to governmental authorities. Shipping and handling fees charged to the Company’s customers are recognized as product revenue in the period shipped and the related costs for providing these services are recorded as a cost of sale. The following is a description of the principal activities from which the Company generates revenue: Product Revenue from the sale of the Company's hardware and perpetual software products is generally recognized at a point in time when the product has been fulfilled and the customer is obligated to pay for the product. The Company also offers several products by subscription, either through term-based license agreements or as SaaS offerings. Revenue for term-based license agreements is recognized at a point in time, when the Company delivers the software license to the customer and the subscription term has commenced. For the Company's SaaS offerings, revenue is recognized ratably as the services are provided. Hardware, including the software run on those devices is considered systems revenue. Perpetual or subscription software offerings that are, or have the ability to be deployed on a standalone basis, along with the Company's SaaS offerings are considered software revenue. When rights of return are present and the Company cannot estimate returns, revenue is recognized when such rights of return lapse. Payment terms to customers are generally net 30 days to net 60 days. Global Services Revenues for post-contract customer support ("PCS") are recognized on a straight-line basis over the service contract term. PCS includes a limited period of telephone support, updates, repair or replacement of any failed product or component that fails during the term of the agreement, bug fixes and rights to upgrades, when and if available. Consulting services are customarily billed at fixed hourly rates, plus out-of-pocket expenses, and revenues are recognized as the consulting is completed. Similarly, training revenue is recognized as the training is completed. Contract Acquisition Costs Sales commissions earned by the Company's sales force are considered incremental and recoverable costs of obtaining a contract with a customer. Sales commissions for initial service contracts and subscription offerings are deferred and then amortized as an expense on a straight-line basis over the period of benefit which management has determined to be 4.5 years and 3 years, respectively. Significant Judgments The Company enters into certain contracts with customers, including flexible consumption programs and multi-year subscriptions, with non-standard terms and conditions. Management exercises significant judgment in assessing contractual terms in these arrangements to identify and evaluate performance obligations. Management allocates consideration to each performance obligation based on relative fair value using standalone selling price and recognizes associated revenue as control is transferred to the customer.
Guarantees And Product Warranties	Guarantees and Product Warranties In the normal course of business to facilitate sales of its products, the Company indemnifies other parties, including customers, resellers, lessors, and parties to other transactions with the Company, with respect to certain matters. The Company has agreed to hold the other party harmless against losses arising from a breach of representations or covenants, or out of intellectual property infringement or other claims made against certain parties. These agreements may limit the time within which an indemnification claim can be made and the amount of the claim. The Company has entered into indemnification agreements with its officers and directors, and the Company’s bylaws contain similar indemnification obligations to the Company’s agents. It is not possible to determine the maximum potential amount under these indemnification agreements due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement.
Research And Development	Research and Development Research and development expenses consist of salaries and related benefits of product development personnel, prototype materials and expenses related to the development of new and improved products, and an allocation of facilities, depreciation and amortization expense. Research and development expenses are reflected in the income statements as incurred.
Advertising	Advertising Advertising costs are expensed as incurred. The Company incurred $15.4 million, $10.0 million and $7.8 million in advertising costs during the fiscal years 2022, 2021 and 2020, respectively.
Income Taxes	Income Taxes Deferred income tax assets and liabilities are determined based upon differences between the financial statement and income tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The realization of deferred tax assets is based on historical tax positions and estimates of future taxable income. A valuation allowance is recorded when it is more-likely-than-not that some of the deferred tax assets will not be realized. The Company assesses whether tax benefits claimed or expected to be claimed on a tax return should be recorded in the financial statements. The Company may recognize the tax benefit from an uncertain tax position only if it is more-likely-than-not that the tax position will be sustained on examination by the taxing authorities, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax benefits to be recognized in the financial statements from such a position is measured as the largest amount of benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. The Company adjusts these liabilities based on a variety of factors, including the evaluation of information not previously available. These adjustments are reflected as increases or decreases to income tax expense in the period in which new information is available. The Company has made an accounting policy election to treat taxes under the global intangible low-taxed income (GILTI) provision as a current period expense.
Foreign Currency	Foreign Currency The functional currency for the Company’s foreign subsidiaries is either the U.S. dollar or the local currency depending on the assessment of management. An entity’s functional currency is determined by the currency of the economic environment in which the majority of cash is generated and expended by the entity. The financial statements of all majority-owned subsidiaries and related entities, with a functional currency other than the U.S. dollar, have been translated into U.S. dollars. All assets and liabilities of the respective entities are translated at year-end exchange rates and all revenues and expenses are translated at average rates during the respective period. Translation adjustments are reported as other comprehensive income (loss) in the consolidated statements of comprehensive income. Foreign currency transaction gains and losses are a result of the effect of exchange rate changes on transactions denominated in currencies other than the functional currency, including U.S. dollars. Gains and losses on those foreign currency transactions are included in determining net income or loss for the period of exchange and are recorded in other income, net. The net effect of foreign currency gains and losses was not material during the fiscal years ended September 30, 2022, 2021 and 2020.
Segments	Segments Management has determined that the Company is organized as, and operates in, one reportable operating segment: the development, marketing and sale of application security and delivery solutions which enable its customers to develop, deploy, operate, secure, and govern applications in any architecture, from on-premises to the public cloud.
Stock-Based Compensation	Stock-based Compensation The Company issues incentive awards to its employees through stock-based compensation consisting of restricted stock units (RSUs). RSUs are payable in shares of the Company’s common stock as the periodic vesting requirements are satisfied, generally over one the date of grant. The value of RSUs is determined using the intrinsic value method and is based on the number of shares granted and the quoted price of the Company’s common stock on the date of grant. The Company offers an Employee Stock Purchase Plan (ESPP) that permits eligible employees to purchase shares of the Company’s common stock at a discount. In determining the fair value of shares issued under the ESPP, the Company uses the Black-Scholes option pricing model. The assumptions within the option pricing model are based on management’s best estimates at that time, which impact the fair value of the ESPP option calculated under the Black-Scholes methodology and, ultimately, the expense that will be recognized over the life of the ESPP option. The Company has also issued stock options as replacement awards, most notably for those assumed as part of business combinations. The Company used the Black-Scholes option pricing model to determine the fair value of the stock option replacement awards. The assumptions within the option pricing model are based on management’s best estimates at that time, which impact the fair value of the option calculated under the Black-Scholes methodology and, ultimately, the expense that will be recognized over the term of the option. The Company accounts for stock-based compensation using the straight-line attribution method for recognizing compensation expense. The Company recognizes compensation expense for only the portion of stock-based awards that are expected to vest. Therefore, the Company applies estimated forfeiture rates that are derived from historical employee termination behavior. Based on historical differences with forfeitures of stock-based awards granted to the Company’s executive officers and Board of Directors versus grants awarded to all other employees, the Company has developed separate forfeiture expectations for these two groups. The Company issues incentive awards to certain current executive officers as part of its annual equity awards program. A portion of the aggregate number of RSUs issued to executive officers vest in equal quarterly increments, and a portion is subject to the Company achieving specified performance goals. In fiscal 2018, the Company's Talent and Compensation Committee adopted a new set of metrics for the performance stock awards, including (1) 50% of the annual performance stock grant is based on achieving certain annual revenue; (2) 25% of the annual performance stock grant is based on achieving an increase in annual software revenue compared to the prior year; and (3) 25% of the annual performance stock grant is based on relative total shareholder return (TSR) benchmarked to the S&P 500 index. In each case, no vesting or payment with respect to a performance goal shall occur unless a minimum threshold is met for the applicable goal. Vesting and payment with respect to the performance goal is linear above the threshold of the applicable goal and is capped at achievement of 200% above target. The Company recognizes compensation costs for awards with performance conditions and market conditions on a straight-line basis over the requisite service period for each separately vesting portion of the award and, for awards with performance conditions, when it concludes it is probable that the performance condition will be achieved. The Company reassesses the probability of vesting at each balance sheet date and adjusts compensation costs based on the probability assessment.
Comprehensive Income	Comprehensive Income Comprehensive income includes certain changes in equity that are excluded from net income. Specifically, unrealized gains or losses on securities and foreign currency translation adjustments. These changes are included in accumulated other comprehensive income or loss.
Recent Accounting Pronouncements	Recently Adopted Accounting Standards In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers. The new guidance requires contract assets and contract liabilities acquired in a business combination to be recognized and measured by the acquirer on the acquisition date in accordance with ASC 606, Revenue from Contracts with Customers. The Company early adopted this accounting standard update beginning in the first quarter of fiscal 2022 and it did not have a material impact on the Company's consolidated financial statements.

Accounting Policies (Tables)

Accounting Policies (Tables)	12 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Schedule of Inventories	Inventories consist of the following (in thousands): September 30, 2022 2021 Finished goods $ 10,164 $ 13,081 Raw materials 58,201 8,974 $ 68,365 $ 22,055
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic and diluted net income per share (in thousands, except per share data): Years Ended September 30, 2022 2021 2020 Numerator Net income $ 322,160 $ 331,241 $ 307,441 Denominator Weighted average shares outstanding — basic 60,274 60,707 60,911 Dilutive effect of common shares from stock options and restricted stock units 823 1,350 467 Weighted average shares outstanding — diluted 61,097 62,057 61,378 Basic net income per share $ 5.34 $ 5.46 $ 5.05 Diluted net income per share $ 5.27 $ 5.34 $ 5.01

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Sep. 30, 2022
Revenue from Contracts with Customers [Abstract]
Capitalized Contract Cost	The table below shows significant movements in capitalized contract acquisition costs (current and noncurrent) for the years ended September 30, 2022, 2021, and 2020 (in thousands): 2022 2021 2020 Balance, beginning of year $ 77,836 $ 70,396 $ 59,446 Additional capitalized contract acquisition costs 37,897 41,719 43,557 Amortization of capitalized contract acquisition costs (38,513) (34,279) (32,607) Balance, end of year $ 77,220 $ 77,836 $ 70,396
Contract with Customer, Asset and Liability	The table below shows significant movements in the deferred revenue balances (current and noncurrent) for the years ended September 30, 2022, 2021, and 2020 (in thousands): 2022 2021 2020 Balance, beginning of year $ 1,489,842 $ 1,272,632 $ 1,198,116 Amounts added but not recognized as revenues 1,167,143 1,122,081 850,022 Deferred revenue acquired through acquisition of businesses 10,591 779 39,000 Revenues recognized related to the opening balance of deferred revenue (975,996) (905,650) (814,506) Balance, end of year $ 1,691,580 $ 1,489,842 $ 1,272,632

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Sep. 30, 2022
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The allocated purchase consideration to assets acquired and liabilities assumed based on preliminary estimated fair values is presented in the following table (in thousands): Estimated Useful Life Assets acquired Deferred tax assets $ 14,036 Other net tangible assets acquired, at fair value 5,481 Cash, cash equivalents, and restricted cash 911 Identifiable intangible assets: Developed technology 11,400 5 years Customer relationships 4,400 5 years Goodwill 43,287 Total assets acquired $ 79,515 Liabilities assumed Deferred revenue $ (10,591) Total liabilities assumed $ (10,591) Net assets acquired $ 68,924 The allocated purchase consideration to assets acquired and liabilities assumed based on preliminary estimated fair values is presented in the following table (in thousands): Estimated Useful Life Assets acquired Cash, cash equivalents, and restricted cash $ 14,012 Other tangible assets acquired, at fair value 7,499 Identifiable intangible assets: Developed technology 59,500 7 years Customer relationships 500 1 year Goodwill 350,863 Total assets acquired 432,374 Liabilities assumed (5,233) Net assets acquired $ 427,141 The allocated purchase consideration to assets acquired and liabilities assumed is presented in the following table (in thousands): Estimated Useful Life Assets acquired Cash, cash equivalents, and restricted cash $ 53,934 Fair value of tangible assets: Accounts receivable 21,077 Deferred tax assets 29,848 Operating lease right-of-use assets 29,644 Other tangible assets 22,571 Identifiable intangible assets: Developed technology 120,000 7 years Customer relationships 21,000 4 years Trade name 9,500 5 years Goodwill 798,867 Total assets acquired $ 1,106,441 Liabilities assumed Deferred revenue $ (39,000) Operating lease liabilities (30,773) Other assumed liabilities (18,571) Total liabilities assumed $ (88,344) Net assets acquired $ 1,018,097

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Schedule Of Financial Assets Measured At Fair Value on A Recurring Basis	The Company's financial assets measured at fair value on a recurring basis subject to the disclosure requirements at September 30, 2022 and September 30, 2021, were as follows (in thousands): Gross Unrealized Classification on Balance Sheet As of September 30, 2022 Fair Value Level Cost or Amortized Cost Gains Losses Aggregate Cash and Cash Equivalents Short-Term Investments Long-Term Investments Changes in fair value recorded in other comprehensive income Money Market Funds Level 1 $ 276,294 $ — $ — $ 276,294 $ 276,294 $ — $ — Corporate bonds and notes Level 2 50,828 — (950) 49,878 912 44,356 4,610 Municipal bonds and notes Level 2 5,018 — (102) 4,916 — 3,812 1,104 U.S. government securities Level 2 84,734 — (660) 84,074 10,120 73,954 — U.S. government agency securities Level 2 5,825 — (75) 5,750 606 4,432 712 Total debt investments $ 422,699 $ — $ (1,787) $ 420,912 $ 287,932 $ 126,554 $ 6,426 Changes in fair value recorded in other net income (expense) Equity investments * $ 3,118 $ — $ — $ 3,118 Total equity investments 3,118 — — 3,118 Total investments $ 424,030 $ 287,932 $ 126,554 $ 9,544 * The fair value of this equity investment is measured at net asset value (NAV) which approximates fair value and is not classified within the fair value hierarchy . Gross Unrealized Classification on Balance Sheet As of September 30, 2021 Fair Value Level Cost or Amortized Cost Gains Losses Aggregate Cash and Cash Equivalents Short-Term Investments Long-Term Investments Changes in fair value recorded in other comprehensive income Money Market Funds Level 1 $ 17,150 $ — $ — $ 17,150 $ 17,150 $ — $ — Certificates of deposit Level 2 255 — — 255 — 255 — Corporate bonds and notes Level 2 243,568 129 (86) 243,611 4,397 186,107 53,107 Municipal bonds and notes Level 2 24,684 2 (9) 24,677 — 13,566 11,111 U.S. government securities Level 2 162,221 14 (12) 162,223 — 102,615 59,608 U.S. government agency securities Level 2 36,053 — (14) 36,039 — 27,087 8,952 Total investments $ 483,931 $ 145 $ (121) $ 483,955 $ 21,547 $ 329,630 $ 132,778
Impairment Charges	Impairment charges were allocated to the following income statement line items for the years ended September 30, 2022, 2021, and 2020 (in thousands): Years Ended September 30, 2022 2021 2020 Cost of net product revenue $ — $ 2,865 $ 241 Cost of net service revenue — 3,492 1,034 Sales and marketing 6,175 11,515 2,876 Research and development — 12,974 2,906 General and administrative — 9,852 2,616 Total impairment charges $ 6,175 $ 40,698 $ 9,673

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	12 Months Ended
	Sep. 30, 2022
Balance Sheet Details [Abstract]
Cash, Cash Equivalents and Restricted Cash	The following table provides a reconciliation of the Company’s cash and cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total cash, cash equivalents and restricted cash shown in the Company’s consolidated statements of cash flows for the periods presented (in thousands): September 30, 2022 2021 Cash and cash equivalents $ 758,012 $ 580,977 Restricted cash included in other assets, net 4,195 3,356 Total cash, cash equivalents and restricted cash $ 762,207 $ 584,333
Inventories	Inventories consist of the following (in thousands): September 30, 2022 2021 Finished goods $ 10,164 $ 13,081 Raw materials 58,201 8,974 $ 68,365 $ 22,055
Other Current Assets	Other current assets consist of the following (in thousands): September 30, 2022 2021 Unbilled receivables $ 319,707 $ 215,396 Prepaid expenses 57,340 59,636 Capitalized contract acquisition costs 34,658 34,265 Other 1 77,609 28,605 $ 489,314 $ 337,902 (1) As of September 30, 2022, includes a deposit of $57.0 million used to support the working capital needs of the Company’s primary contract manufacturer's procurement of components used in the manufacturing of system hardware.
Property, Plant and Equipment	Property and Equipment Property and equipment are stated at net book value. Depreciation of property and equipment is provided using the straight-line method over the estimated useful lives of the assets, ranging from two Property and equipment consist of the following (in thousands): September 30, 2022 2021 Computer equipment $ 168,204 $ 166,846 Software 86,036 94,169 Office furniture and equipment 41,619 45,204 Leasehold improvements 173,689 174,504 469,548 480,723 Accumulated depreciation and amortization (301,366) (289,559) $ 168,182 $ 191,164
Goodwill	Changes in the carrying amount of goodwill during fiscal years 2022 and 2021 are summarized as follows (in thousands): Balance, September 30, 2020 $ 1,858,966 Acquisition of Volterra, Inc. 351,417 Other 6,170 Balance, September 30, 2021 2,216,553 Acquisition of Threat Stack, Inc. 43,956 Other (1,227) Balance, September 30, 2022 $ 2,259,282
Other Assets	Other assets consist of the following (in thousands): September 30, 2022 2021 Intangible assets $ 200,288 $ 237,178 Unbilled receivables 224,780 158,885 Capitalized contract acquisition costs 42,561 43,571 Other 48,493 32,924 $ 516,122 $ 472,558
Intangible Assets	Intangible assets are included in other assets on the consolidated balance sheets and consist of the following (in thousands): September 30, 2022 September 30, 2021 Gross Accumulated Net Carrying Gross Accumulated Net Carrying Developed technology $ 319,436 $ (151,332) $ 168,104 $ 305,673 $ (111,279) $ 194,394 Customer relationships 46,142 (25,630) 20,512 41,742 (17,865) 23,877 Patents and trademarks 23,504 (19,255) 4,249 20,260 (17,180) 3,080 Trade names 24,973 (17,550) 7,423 24,973 (9,146) 15,827 Non-compete covenants 2,260 (2,260) — 2,260 (2,260) — $ 416,315 $ (216,027) $ 200,288 $ 394,908 $ (157,730) $ 237,178
Estimated Amortization Expense For Intangible Assets	For intangible assets held as of September 30, 2022, amortization expense for the five succeeding fiscal years is as follows (in thousands): 2023 $ 51,303 2024 46,030 2025 41,559 2026 36,805 2027 15,526 $ 191,223
Accrued Liabilities	Accrued liabilities consist of the following (in thousands): September 30, 2022 2021 Payroll and benefits $ 165,437 $ 179,147 Operating lease liabilities, current 42,523 49,286 Income and other tax accruals 41,217 44,075 Other 60,642 68,979 $ 309,819 $ 341,487
Other Long-term Liabilities	Other long-term liabilities consist of the following (in thousands): September 30, 2022 2021 Income taxes payable $ 59,553 $ 66,081 Other 8,157 9,155 $ 67,710 $ 75,236

Debt Facilities (Tables)

Debt Facilities (Tables)	12 Months Ended
	Sep. 30, 2022
Debt Disclosure [Abstract]
Schedule of Maturities of Long-term Debt	The following table presents the scheduled principal maturities as of September 30, 2022 (in thousands): Fiscal Years Ending September 30: 2023 $ 350,000 Total $ 350,000

Leases (Tables)

Leases (Tables)	12 Months Ended
	Sep. 30, 2022
Leases [Abstract]
Lease, Cost	The components of the Company's operating lease expenses for the years ended September 30, 2022, 2021, and 2020 were as follows (in thousands): Fiscal year ended September 30, 2022 2021 2020 Operating lease expense $ 47,302 $ 47,993 $ 49,925 Short-term lease expense 2,465 2,953 3,563 Variable lease expense 23,209 25,200 21,980 Total lease expense $ 72,976 $ 76,146 $ 75,468
Assets And Liabilities Lessee	Supplemental balance sheet information related to the Company's operating leases was as follows (in thousands, except lease term and discount rate): September 30, 2022 2021 Operating lease right-of-use assets, net $ 227,475 $ 244,934 Operating lease liabilities, current 1 42,523 49,286 Operating lease liabilities, long-term 272,376 296,945 Total operating lease liabilities $ 314,899 $ 346,231 Weighted average remaining lease term (in years) 9.2 9.7 Weighted average discount rate 2.66 % 2.60 % (1) Current portion of operating lease liabilities is included in accrued liabilities on the Company's consolidated balance sheets.
Lessee, Operating Lease, Liability, Maturity	As of September 30, 2022, the future operating leases payments for each of the next five years and thereafter is as follows (in thousands): Fiscal Years Ending September 30: Operating Lease 2023 $ 50,427 2024 46,288 2025 38,793 2026 29,241 2027 28,592 Thereafter 166,585 Total lease payments 359,926 Less: imputed interest (45,027) Total lease liabilities $ 314,899

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Components Of Income Before Income Taxes	The United States and international components of income before income taxes are as follows (in thousands): Years Ended September 30, 2022 2021 2020 United States $ 217,323 $ 189,398 $ 216,409 International 168,070 197,539 179,988 $ 385,393 $ 386,937 $ 396,397
Schedule Of Provision For Income Taxes (Benefit)	The provision for income taxes consists of the following (in thousands): Years Ended September 30, 2022 2021 2020 Current U.S. federal $ 35,259 $ 53,107 $ 26,978 State 14,592 16,686 4,230 Foreign 54,079 62,832 50,368 Total 103,930 132,625 81,576 Deferred U.S. federal (28,721) (61,739) 10,875 State (11,332) (15,294) (1,121) Foreign (644) 104 (2,374) Total (40,697) (76,929) 7,380 $ 63,233 $ 55,696 $ 88,956
Schedule Of Effective Tax Rate Differs From The U.S. Federal Statutory Rate	The effective tax rate differs from the U.S. federal statutory rate as follows (in thousands): Years Ended September 30, 2022 2021 2020 Income tax provision at statutory rate $ 80,933 $ 81,257 $ 83,243 State taxes, net of federal benefit 6,012 5,118 4,258 Tax impact of foreign operations (21,435) (26,881) (7,693) Research and development and other credits (18,917) (18,055) (11,843) Stock-based and other compensation 15,070 12,740 18,002 Other 1,570 1,517 2,989 $ 63,233 $ 55,696 $ 88,956
Schedule Of Tax Effects To Deferred Tax Assets And Liabilities	The tax effects of the temporary differences that give rise to the deferred tax assets and liabilities are as follows (in thousands): Years Ended September 30, 2022 2021 Deferred tax assets Net operating loss carry-forwards $ 42,849 $ 41,252 Capitalized research and development costs 158,206 95,259 Accrued compensation and benefits 14,068 13,207 Stock-based compensation 10,389 12,829 Deferred revenue 32,244 30,115 Lease liabilities 21,572 23,747 Other accruals and reserves 18,797 18,450 Tax credit carryforwards 28,858 34,187 Depreciation 505 580 327,488 269,626 Valuation allowance (46,136) (40,404) 281,352 229,222 Deferred tax liabilities Purchased intangibles (57,350) (57,219) Depreciation (22,278) (26,516) Deferred costs (12,987) (13,057) Other accruals and reserves (8,153) (6,651) (100,768) (103,443) Net deferred tax assets $ 180,584 $ 125,779
Schedule Of Reconciliation Of Beginning And Ending Amount Of Unrecognized Tax Benefits	The following table provides a reconciliation of the beginning and ending amount of unrecognized tax benefits in fiscal years 2022, 2021 and 2020 (in thousands): 2022 2021 2020 Balance, beginning of period $ 70,814 $ 51,767 $ 42,287 Gross increases related to prior period tax positions 4,816 14,867 8,664 Gross decreases related to prior period tax positions (10,538) — (1,051) Gross increases related to current period tax positions 10,203 12,595 9,272 Decreases relating to settlements with tax authorities — (321) (3,578) Reductions due to lapses of statute of limitations (8,455) (8,094) (3,827) Balance, end of period $ 66,840 $ 70,814 $ 51,767

Equity (Tables)

Equity (Tables)	12 Months Ended
	Sep. 30, 2022
Equity [Abstract]
Common Stock Repurchased and Retired	The following table summarizes the Company's repurchases and retirements of its common stock under its Stock Repurchase Program, including the ASR (in thousands, except per share data): Years Ended September 30, 2022 2021 2020 Shares repurchased 2,611 2,501 799 Average price per share $ 191.47 $ 199.90 $ 125.10 Amount repurchased $ 500,023 $ 500,000 $ 100,016

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Sep. 30, 2022
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Schedule Of Assumptions In Determining The Fair Value Of Shares Issued Under The Employee Stock Purchase Plan	In determining the fair value of the right to purchase under the Employee Stock Purchase Plan, the Company uses the Black-Scholes option pricing model that employs the following key assumptions: Employee Stock Purchase Plan 2022 2021 2020 Risk-free interest rate 0.05% - 0.62% 0.07% - 0.13% 1.10% - 1.97% Expected dividend — — — Expected term 0.5 years 0.5 years 0.5 years Expected volatility 26.34% - 31.57% 29.67% - 37.22% 26.32% - 41.94%
Schedule Of Summary Of Restricted Stock Unit Activity	A summary of restricted stock unit activity under the Plan is as follows: Performance Stock Units Restricted Stock Units Outstanding Weighted Outstanding Weighted Balance, September 30, 2021 230,926 $ 136.47 1,340,548 $ 141.90 Units granted 111,283 200.74 1,118,854 206.45 Units vested (119,889) 215.12 (1,122,583) 188.04 Units cancelled (14,204) 151.07 (199,200) 170.35 Balance, September 30, 2022 208,116 $ 169.99 1,137,619 $ 184.59
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	In determining the fair value of the portion of the performance awards based on Total Shareholder Return, the Company uses a Monte Carlo simulation model that employs the following key assumptions: Expected Volatility Fair Value Expected Term Risk-Free Index Expected Grant Date per Share (in years) Interest Rate F5 Members Dividend November 1, 2021 Tranche 1 $ 283.35 0.91 0.13 % 26.21 % 27.27 % — Tranche 2 $ 302.53 1.91 0.47 % 35.13 % 42.87 % — Tranche 3 $ 308.76 2.91 0.76 % 32.54 % 38.24 % —
Schedule of Nonvested Restricted Stock Units Activity	As of September 30, 2022, the following annual equity grants for executive officers or a portion thereof are outstanding: Grant Date RSUs Granted Vesting Schedule Vesting Period Date Fully Vested November 1, 2021 160,384 Quarterly, Annually 1,2 3 years November 1, 2024 November 2, 2020 257,568 Quarterly, Annually 1 3 years November 1, 2023 November 1, 2019 228,616 Quarterly, Annually 1 3 years November 1, 2022 November 1, 2018 144,066 Quarterly, Annually 1 3 years November 1, 2021 (1) 50% of the annual equity grant vests in equal quarterly increments and 50% is subject to the Company achieving specified annual performance goals. (2) For the Company's Chief Executive Officer, 40% of the annual equity grant vests in equal quarterly increments and 60% is subject to the Company achieving specified annual performance goals.
Schedule Of Stock Option Activity	A summary of stock option activity under all of the Company’s plans is as follows: Options Outstanding Number of Weighted Balance, September 30, 2021 324,624 $ 30.83 Options granted — — Options exercised (143,128) 25.24 Options cancelled (16,700) 53.98 Balance, September 30, 2022 164,796 $ 33.34
Schedule Of Outstanding Stock Options Currently Exercisable, Vested And Expected To Vest	A summary of options outstanding that are exercisable and that have vested and are expected to vest as of September 30, 2022 is as follows: Number of Weighted Weighted Aggregate (In thousands) Stock options outstanding 164,796 6.45 $ 33.34 $ 18,357 Exercisable 127,072 6.20 $ 30.76 $ 14,482 Vested and expected to vest 162,713 6.42 $ 33.20 $ 18,147 (1) Aggregate intrinsic value represents the difference between the fair value of the Company’s common stock underlying these options at September 30, 2022 and the related exercise prices.
Schedule Of Equity Based Awards (Including Stock Options And Restricted Stock Units)	As of September 30, 2022, equity based awards (including stock options and restricted stock units) are available for future issuance as follows: Awards Balance, September 30, 2021 1,988,410 Granted (1,255,975) Cancelled 327,201 Additional shares reserved (terminated), net 1,013,142 Balance, September 30, 2022 2,072,778

Net Income Per Share (Tables)

Net Income Per Share (Tables)	12 Months Ended
	Sep. 30, 2022
Net Income Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table sets forth the computation of basic and diluted net income per share (in thousands, except per share data): Years Ended September 30, 2022 2021 2020 Numerator Net income $ 322,160 $ 331,241 $ 307,441 Denominator Weighted average shares outstanding — basic 60,274 60,707 60,911 Dilutive effect of common shares from stock options and restricted stock units 823 1,350 467 Weighted average shares outstanding — diluted 61,097 62,057 61,378 Basic net income per share $ 5.34 $ 5.46 $ 5.05 Diluted net income per share $ 5.27 $ 5.34 $ 5.01

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Sep. 30, 2022
Segments, Geographical Areas [Abstract]
Schedule Of Revenues By Geographic Region	The following presents revenues by geographic region (in thousands): Years Ended September 30, 2022 2021 2020 Americas: United States $ 1,487,144 $ 1,365,625 $ 1,221,190 Other 85,711 92,111 95,878 Total Americas 1,572,855 1,457,736 1,317,068 EMEA 634,759 667,219 593,307 Asia Pacific 488,231 478,461 440,447 $ 2,695,845 $ 2,603,416 $ 2,350,822
Schedule of Revenues by Systems and Software	The following presents net product revenues by systems and software (in thousands): Years Ended September 30, 2022 2021 2020 Net product revenues Systems revenue $ 651,902 $ 748,192 $ 668,313 Software revenue 665,215 498,892 357,543 Total net product revenue $ 1,317,117 $ 1,247,084 $ 1,025,856
Schedule of Revenue by Major Customers by Reporting Segments	The following distributors of the Company's products accounted for more than 10% of total net revenue: Years Ended September 30, 2022 2021 2020 Ingram Micro, Inc. 20.0 % 19.2 % 16.7 % Synnex Corporation 13.4 % 11.1 % —
Schedule of Receivables by Major Customers by Reporting Segments	The following distributors of the Company's products accounted for more than 10% of total receivables: September 30, 2022 2021 Ingram Micro, Inc. 12.9 % 12.6 % Synnex Corporation 12.6 % 11.9 % Carahsoft Technology 16.2 % 11.5 %
Long-lived Assets by Geographic Areas [Table Text Block]	The Company tracks assets by physical location. Long-lived assets consist of property and equipment, net, and are shown below (in thousands): September 30, 2022 2021 United States $ 134,699 $ 153,030 EMEA 17,376 20,526 Other countries 16,107 17,608 $ 168,182 $ 191,164

Summary Of Significant Accoun_3

Summary Of Significant Accounting Policies - Narrative (Details)		12 Months Ended
	Oct. 01, 2021 USD ($)	Sep. 30, 2022 USD ($) segment	Sep. 30, 2021 USD ($) segment	Sep. 30, 2020 USD ($) segment
Segment Reporting [Abstract]
Number of Reportable Segments | segment		1	1	1
Advertising
Advertising Expense		$ 15,400,000	$ 10,000,000	$ 7,800,000
Restricted Stock Units (RSUs) [Member]
Restricted Stock Award
Award vesting period		2 years	2 years	2 years
Restricted Stock Units (RSUs) [Member] | Annual Equity Program [Member]
Restricted Stock Award
Percentage Of Annual Performance Stock Grant Based On Achieving Annual Revenue Goal		50%
Percentage Of Annual Performance Stock Grant Based On Achieving Annual Increase in Stand-alone Software Goal		25%
Percentage Of Annual Performance Stock Grant Based On Achieving Relative Total Shareholder Return Benchmarked to the S&P 500 Index Goal		25%
Percentage Of Over-Achievement To Which Annual Performance Based Vesting Cannot Exceed		200%
Maintenance [Member]
Revenue Recognition
Capitalized Contract Cost, Amortization Period		4 years 6 months
Subscription and Circulation [Member]
Revenue Recognition
Capitalized Contract Cost, Amortization Period		3 years
Hardware [Member]
Guarantees and Product Warranties
Standard Product Warranty Period		1 year
Threat Stack, Inc.
Business Combinations
Total Purchase Price	$ 68,900,000
Threat Stack, Inc. | Developed Technology Rights
Business Combinations
Identifiable intangible assets:	$ 11,400,000
Minimum
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life		2 years
Property, Plant and Equipment [Abstract]
Property and equipment, useful life		2 years
Revenue Recognition
Accounts Receivable Payment Term Period In Days		30 days
Restricted Stock Award
Award vesting period		1 year
Minimum | Software and Software Development Costs [Member]
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life		3 years
Maximum
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life		15 years
Property, Plant and Equipment [Abstract]
Property and equipment, useful life		5 years
Revenue Recognition
Accounts Receivable Payment Term Period In Days		60 days
Restricted Stock Award
Award vesting period		4 years
Maximum | Software and Software Development Costs [Member]
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life		5 years

Summary Of Significant Accoun_4

Summary Of Significant Accounting Policies - Schedule Of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Accounting Policies [Abstract]
Finished goods	$ 10,164	$ 13,081
Raw materials	58,201	8,974
Inventories, Total	$ 68,365	$ 22,055

Summary Of Significant Accoun_5

Summary Of Significant Accounting Policies - Property And Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Property, Plant and Equipment [Line Items]
Computer equipment	$ 168,204	$ 166,846
Capitalized Computer Software, Gross	86,036	94,169
Office furniture and equipment	41,619	45,204
Leasehold improvements	173,689	174,504
Property and equipment, gross	469,548	480,723
Accumulated depreciation and amortization	(301,366)	(289,559)
Property, Plant and Equipment, Net	$ 168,182	$ 191,164
Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	2 years
Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years

Summary Of Significant Accoun_6

Summary Of Significant Accounting Policies - Schedule Of Computation Of Basic And Diluted Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Accounting Policies [Abstract]
Net income	$ 322,160	$ 331,241	$ 307,441
Weighted average shares outstanding - basic	60,274	60,707	60,911
Dilutive effect of common shares from stock options and restricted stock units	823	1,350	467
Weighted average shares outstanding - diluted	61,097	62,057	61,378
Basic net income per share (USD per share)	$ 5.34	$ 5.46	$ 5.05
Diluted net income per share (USD per share)	$ 5.27	$ 5.34	$ 5.01

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Capitalized Contract Acquisition Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Capitalized Contract Acquisition Costs [Abstract]
Balance, beginning of year	$ 77,836	$ 70,396	$ 59,446
Additional capitalized contract acquisition costs	37,897	41,719	43,557
Amortization of capitalized contract acquisition costs	(38,513)	(34,279)	(32,607)
Balance, end of year	$ 77,220	$ 77,836	$ 70,396

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Change in Contract with Customer, Liability [Roll Forward]
Balance, beginning of year	$ 1,489,842	$ 1,272,632	$ 1,198,116
Amounts added but not recognized as revenues	1,167,143	1,122,081	850,022
Deferred revenue acquired through acquisition of businesses	10,591	779	39,000
Revenues recognized related to the opening balance of deferred revenue	(975,996)	(905,650)	(814,506)
Balance, end of year	$ 1,691,580	$ 1,489,842	$ 1,272,632

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Capitalized Contract Cost, Amortization	$ 38,513,000	$ 34,279,000	$ 32,607,000
Capitalized Contract Cost, Impairment Loss	$ 0	$ 0	$ 0

Revenue from Contracts with C_6

Revenue from Contracts with Customers - Remaining Performance Obligations. (Details) $ in Billions	Sep. 30, 2022 USD ($)
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 1.7
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Percentage	63.10%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Percentage	23%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months

Business Combinations - Purchas

Business Combinations - Purchase Price Allocation (Details) - USD ($)	Oct. 01, 2021	Jan. 22, 2021	Jan. 24, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Fair Value of intangible Assets Abstract [Abstract]
Goodwill				$ 2,259,282,000	$ 2,216,553,000	$ 1,858,966,000
Threat Stack, Inc.
AssetsAcquiredAbstract [Abstract]
Cash, cash equivalents, and restricted cash	$ 911,000
Fair Value of intangible Assets Abstract [Abstract]
Deferred tax assets	14,036,000
Other tangible assets acquired, at fair value	$ 5,481,000
Identifiable Intangible Assets Useful Life	5 years
Goodwill	$ 43,287,000
Total assets acquired	79,515,000
Liabilities assumed
Deferred revenue	(10,591,000)
Total liabilities assumed	(10,591,000)
Net assets acquired	68,924,000
Threat Stack, Inc. | Developed Technology Rights
Fair Value of intangible Assets Abstract [Abstract]
Identifiable intangible assets:	$ 11,400,000
Identifiable Intangible Assets Useful Life	5 years
Threat Stack, Inc. | Customer Relationships
Fair Value of intangible Assets Abstract [Abstract]
Identifiable intangible assets:	$ 4,400,000
Identifiable Intangible Assets Useful Life	5 years
Volterra, Inc.
AssetsAcquiredAbstract [Abstract]
Cash, cash equivalents, and restricted cash		$ 14,012,000
Fair Value of intangible Assets Abstract [Abstract]
Other tangible assets acquired, at fair value		$ 7,499,000
Identifiable Intangible Assets Useful Life		6 years 11 months 12 days
Goodwill		$ 350,863,000
Total assets acquired		432,374,000
Liabilities assumed
Total liabilities assumed		(5,233,000)
Net assets acquired		427,141,000
Volterra, Inc. | Developed Technology Rights
Fair Value of intangible Assets Abstract [Abstract]
Identifiable intangible assets:		$ 59,500,000
Identifiable Intangible Assets Useful Life		7 years
Volterra, Inc. | Customer Relationships
Fair Value of intangible Assets Abstract [Abstract]
Identifiable intangible assets:		$ 500,000
Identifiable Intangible Assets Useful Life		1 year
Shape Security, Inc.
AssetsAcquiredAbstract [Abstract]
Cash, cash equivalents, and restricted cash			$ 53,934,000
Fair Value of intangible Assets Abstract [Abstract]
Accounts receivable			21,077,000
Deferred tax assets			29,848,000
Operating lease right-of-use assets			29,644,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other			$ 22,571,000
Identifiable Intangible Assets Useful Life			6 years 6 months
Goodwill			$ 798,867,000
Total assets acquired			1,106,441,000
Liabilities assumed
Deferred revenue			(39,000,000)
Operating lease liabilities			(30,773,000)
Other assumed liabilities			(18,571,000)
Total liabilities assumed			(88,344,000)
Net assets acquired			1,018,097,000
Shape Security, Inc. | Developed Technology Rights
Fair Value of intangible Assets Abstract [Abstract]
Identifiable intangible assets:			$ 120,000,000
Identifiable Intangible Assets Useful Life			7 years
Shape Security, Inc. | Customer Relationships
Fair Value of intangible Assets Abstract [Abstract]
Identifiable intangible assets:			$ 21,000,000
Identifiable Intangible Assets Useful Life			4 years
Shape Security, Inc. | Trade Names
Fair Value of intangible Assets Abstract [Abstract]
Identifiable intangible assets:			$ 9,500,000
Identifiable Intangible Assets Useful Life			5 years

Business Combinations - Narrati

Business Combinations - Narrative (Details) - USD ($) $ in Thousands				12 Months Ended
	Oct. 01, 2021	Jan. 22, 2021	Jan. 24, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Goodwill, Other Increase (Decrease)				$ (1,227)	$ 6,170
Threat Stack, Inc.
Business Acquisition [Line Items]
Total Purchase Price	$ 68,900
Identifiable Intangible Assets Useful Life	5 years
Volterra, Inc.
Business Acquisition [Line Items]
Total Purchase Price		$ 427,200
Identifiable Intangible Assets Useful Life		6 years 11 months 12 days
Volterra, Inc. | General and Administrative Expense
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs					$ 9,500
Shape Security, Inc.
Business Acquisition [Line Items]
Total Purchase Price			$ 1,000,000
Transaction Costs			$ 23,200
Identifiable Intangible Assets Useful Life			6 years 6 months
Shape Security, Inc. | General and Administrative Expense
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs						$ 15,300
Developed Technology Rights | Threat Stack, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life	5 years
Developed Technology Rights | Volterra, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life		7 years
Developed Technology Rights | Shape Security, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life			7 years
Customer Relationships | Threat Stack, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life	5 years
Customer Relationships | Volterra, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life		1 year
Customer Relationships | Shape Security, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life			4 years
Trade Names | Shape Security, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life			5 years

Fair Value Assets - Measured on

Fair Value Assets - Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value	$ 287,932	$ 21,547
Debt Securities, Available-for-sale, Amortized Cost	422,699	483,931
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax	0	145
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax	(1,787)	(121)
Debt Securities, Available-for-Sale	420,912	483,955
Debt Securities, Available-for-sale, Current	126,554	329,630
Debt Securities, Available-for-sale, Noncurrent	6,426	132,778
Equity Securities, FV-NI	3,118
Equity Securities, FV-NI, Current	0
Equity Securities, FV-NI, Noncurrent	3,118
Investments, Fair Value Disclosure	424,030
Short-term investments	126,554	329,630
Long-term investments	9,544	132,778
Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value	276,294	17,150
Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Amortized Cost		255
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax		0
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		0
Corporate Bonds And Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	50,828	243,568
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax	0	129
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax	(950)	(86)
Municipal Bonds And Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	5,018	24,684
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax	0	2
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax	(102)	(9)
US Government Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	84,734	162,221
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax	0	14
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax	(660)	(12)
US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	5,825	36,053
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax	(75)	(14)
Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	3,118
Equity Securities, FV-NI, Current	0
Equity Securities, FV-NI, Noncurrent	3,118
Fair Value, Recurring [Member] | Level 1 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value	276,294	17,150
Fair Value, Recurring [Member] | Level 2 | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale		255
Debt Securities, Available-for-sale, Current		255
Debt Securities, Available-for-sale, Noncurrent		0
Fair Value, Recurring [Member] | Level 2 | Corporate Bonds And Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value	912	4,397
Debt Securities, Available-for-Sale	49,878	243,611
Debt Securities, Available-for-sale, Current	44,356	186,107
Debt Securities, Available-for-sale, Noncurrent	4,610	53,107
Fair Value, Recurring [Member] | Level 2 | Municipal Bonds And Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	4,916	24,677
Debt Securities, Available-for-sale, Current	3,812	13,566
Debt Securities, Available-for-sale, Noncurrent	1,104	11,111
Fair Value, Recurring [Member] | Level 2 | US Government Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value	10,120
Debt Securities, Available-for-Sale	84,074	162,223
Debt Securities, Available-for-sale, Current	73,954	102,615
Debt Securities, Available-for-sale, Noncurrent	0	59,608
Fair Value, Recurring [Member] | Level 2 | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value	606
Debt Securities, Available-for-Sale	5,750	36,039
Debt Securities, Available-for-sale, Current	4,432	27,087
Debt Securities, Available-for-sale, Noncurrent	$ 712	$ 8,952

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Impairment Charges by Income Statement Line Item (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Property, Plant and Equipment [Line Items]
Impairment of assets	$ 6,175	$ 40,698	$ 9,673
Cost of net product revenue
Property, Plant and Equipment [Line Items]
Impairment of assets	0	2,865	241
Cost of net service revenue
Property, Plant and Equipment [Line Items]
Impairment of assets	0	3,492	1,034
Selling and Marketing Expense
Property, Plant and Equipment [Line Items]
Impairment of assets	6,175	11,515	2,876
Research and Development Expense
Property, Plant and Equipment [Line Items]
Impairment of assets	0	12,974	2,906
General and Administrative Expense
Property, Plant and Equipment [Line Items]
Impairment of assets	$ 0	$ 9,852	$ 2,616

Fair Value Measurements - Impai

Fair Value Measurements - Impairment of Assets Measured at Fair Value on a Nonrecurring Basis Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2022	Sep. 30, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Operating Lease, Impairment Loss	$ 23.5	$ 6.7		$ 9.7
Fair Value, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of Intangible Assets (Excluding Goodwill)			$ 6.2
Fair Value, Nonrecurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Operating Lease, Impairment Loss	23.5	6.7		$ 9.7
Tangible Asset Impairment Charges	$ 10.3	$ 0.2

Balance Sheet Details - Cash, C

Balance Sheet Details - Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Balance Sheet Details [Abstract]
Cash and Cash Equivalents, at Carrying Value	$ 758,012	$ 580,977
Restricted Cash	4,195	3,356
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 762,207	$ 584,333	$ 852,826	$ 602,254

Balance Sheet Details - Invento

Balance Sheet Details - Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Details [Abstract]
Finished goods	$ 10,164	$ 13,081
Raw materials	58,201	8,974
Inventory, Net	$ 68,365	$ 22,055

Balance Sheet Details - Other C

Balance Sheet Details - Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Details [Abstract]
Unbilled receivables	$ 319,707	$ 215,396
Prepaid expenses	57,340	59,636
Capitalized contract acquisition costs	34,658	34,265
Other1	77,609	28,605
Other Assets, Current	489,314	$ 337,902
Deposit Assets	$ 57,000

Balance Sheet Details - Propert

Balance Sheet Details - Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Details [Abstract]
Machinery and Equipment, Gross	$ 168,204	$ 166,846
Capitalized Computer Software, Gross	86,036	94,169
Furniture and Fixtures, Gross	41,619	45,204
Leasehold Improvements, Gross	173,689	174,504
Property, Plant and Equipment, Gross	469,548	480,723
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(301,366)	(289,559)
Property, Plant and Equipment, Net	$ 168,182	$ 191,164

Balance Sheet Details - Goodwil

Balance Sheet Details - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Details [Abstract]
Goodwill, Beginning Balance	$ 2,216,553	$ 1,858,966
Goodwill, Acquired During Period	43,956	351,417
Goodwill, Other Increase (Decrease)	(1,227)	6,170
Goodwill, Ending Balance	$ 2,259,282	$ 2,216,553

Balance Sheet Details - Other A

Balance Sheet Details - Other Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Details [Abstract]
Intangible assets	$ 200,288	$ 237,178
Unbilled receivables	224,780	158,885
Capitalized contract acquisition costs	42,561	43,571
Other	48,493	32,924
Other Assets, Noncurrent	$ 516,122	$ 472,558

Balance Sheet Details - Intangi

Balance Sheet Details - Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 416,315	$ 394,908
Accumulated Amortization	(216,027)	(157,730)
Net Carrying Amount	200,288	237,178
Amortization of Intangible Assets	36,400	48,700	$ 34,600
Developed Technology Rights
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	319,436	305,673
Accumulated Amortization	(151,332)	(111,279)
Net Carrying Amount	168,104	194,394
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	46,142	41,742
Accumulated Amortization	(25,630)	(17,865)
Net Carrying Amount	20,512	23,877
Patents And Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	23,504	20,260
Accumulated Amortization	(19,255)	(17,180)
Net Carrying Amount	4,249	3,080
Trade Names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	24,973	24,973
Accumulated Amortization	(17,550)	(9,146)
Net Carrying Amount	7,423	15,827
Non-Compete Covenants [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,260	2,260
Accumulated Amortization	(2,260)	(2,260)
Net Carrying Amount	$ 0	$ 0

Balance Sheet Details - Estimat

Balance Sheet Details - Estimated Amortization Expense For Intangible Assets (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Balance Sheet Details [Abstract]
2023	$ 51,303
2024	46,030
2025	41,559
2026	36,805
2027	15,526
Total estimated amortization expense	$ 191,223

Balance Sheet Details - Accrued

Balance Sheet Details - Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Details [Abstract]
Payroll and benefits	$ 165,437	$ 179,147
Operating lease liabilities, current	42,523	49,286
Income and other tax accruals	41,217	44,075
Other	60,642	68,979
Accrued Liabilities, Current	$ 309,819	$ 341,487

Balance Sheet Details - Other L

Balance Sheet Details - Other Long-term Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Details [Abstract]
Income taxes payable	$ 59,553	$ 66,081
Other	8,157	9,155
Other Liabilities, Noncurrent	$ 67,710	$ 75,236

Balance Sheet Details - Narrati

Balance Sheet Details - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Property, Plant and Equipment [Line Items]
Depreciation and amortization			$ 115,609	$ 115,424	$ 95,857
Fair Value, Inputs, Level 3 | Fair Value, Nonrecurring
Property, Plant and Equipment [Line Items]
Tangible Asset Impairment Charges	$ 10,300	$ 200
Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation and amortization			$ 56,000	$ 61,300	$ 59,500

Debt Facilities - Long-term Deb

Debt Facilities - Long-term Debt Maturities (Details) - Term Loan Facility [Member] $ in Thousands	Sep. 30, 2022 USD ($)
Debt Instrument [Line Items]
2023	$ 350,000
Total	$ 350,000

Debt Facilities - Narrative (De

Debt Facilities - Narrative (Details)			12 Months Ended
	Jan. 31, 2020 USD ($)	Jan. 24, 2020 USD ($)	Sep. 30, 2022 USD ($) extension	Sep. 30, 2021
Term Loan Facility [Member]
Debt Instrument [Line Items]
Aggregate Principal Amount		$ 400,000,000
Debt Issuance Costs		$ 2,200,000	$ 200,000
Redemption Percentage		1.25%
Long-term Debt			$ 350,000,000
Interest Rate at Period End			2.19%	1.361%
Term Loan Facility [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis Spread on Variable Rate			1.125%
Term Loan Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum
Debt Instrument [Line Items]
Basis Spread on Variable Rate		1.125%
Term Loan Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum
Debt Instrument [Line Items]
Basis Spread on Variable Rate		1.75%
Term Loan Facility [Member] | Alternate Base Rate [Member]
Debt Instrument [Line Items]
Basis Spread on Variable Rate			0.125%
Term Loan Facility [Member] | Alternate Base Rate [Member] | Minimum
Debt Instrument [Line Items]
Basis Spread on Variable Rate		0.125%
Term Loan Facility [Member] | Alternate Base Rate [Member] | Maximum
Debt Instrument [Line Items]
Basis Spread on Variable Rate		0.75%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Aggregate Principal Amount	$ 350,000,000
Conditional Increase In Borrowing Capacity	$ 150,000,000
Number Of Extensions | extension			2
Length Of Extension Period			1 year
Long-term Line of Credit			$ 0
Outstanding Line of Credit Balance			$ 350,000,000
Revolving Credit Facility [Member] | Minimum
Debt Instrument [Line Items]
Commitment Fee Percentage	0.125%
Revolving Credit Facility [Member] | Maximum
Debt Instrument [Line Items]
Commitment Fee Percentage	0.30%
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum
Debt Instrument [Line Items]
Basis Spread on Variable Rate	1.125%
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum
Debt Instrument [Line Items]
Basis Spread on Variable Rate	1.75%
Revolving Credit Facility [Member] | Alternate Base Rate [Member] | Minimum
Debt Instrument [Line Items]
Basis Spread on Variable Rate	0.125%
Revolving Credit Facility [Member] | Alternate Base Rate [Member] | Maximum
Debt Instrument [Line Items]
Basis Spread on Variable Rate	0.75%

Leases - Operating Lease Expens

Leases - Operating Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Operating lease expense	$ 47,302	$ 47,993	$ 49,925
Short-term lease expense	2,465	2,953	3,563
Variable lease expense	23,209	25,200	21,980
Total lease expense	$ 72,976	$ 76,146	$ 75,468

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Leases [Abstract]
Operating lease right-of-use assets	$ 227,475	$ 244,934
Operating lease liabilities, current1	42,523	49,286
Operating lease liabilities, long-term	272,376	296,945
Total lease liabilities	$ 314,899	$ 346,231
Weighted average remaining lease term (in years)	9 years 2 months 12 days	9 years 8 months 12 days
Weighted average discount rate	2.66%	2.60%

Leases - Maturities of Lease Li

Leases - Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Leases [Abstract]
2023	$ 50,427
2024	46,288
2025	38,793
2026	29,241
2027	28,592
Thereafter	166,585
Total lease payments	359,926
Less: imputed interest	(45,027)
Total lease liabilities	$ 314,899	$ 346,231

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2022 USD ($) ft²	Sep. 30, 2020 USD ($)
Lessee, Lease, Description [Line Items]
Sublease Income			$ 21.6
Lessor, Operating Lease, Payments to be Received, Next Twelve Months			7.5
Lessor, Operating Lease, Payments to be Received, Two To Four Years			$ 14.1
Operating Lease, Impairment Loss	$ 23.5	$ 6.7		$ 9.7
Office Building [Member]
Lessee, Lease, Description [Line Items]
Operating Lease, Number of Square Feet | ft²			515,000

Income Taxes - Components Of In

Income Taxes - Components Of Income Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
United States	$ 217,323	$ 189,398	$ 216,409
International	168,070	197,539	179,988
Income before income taxes	$ 385,393	$ 386,937	$ 396,397

Income Taxes - Schedule Of Prov

Income Taxes - Schedule Of Provision For Income Taxes (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Current, U.S. federal	$ 35,259	$ 53,107	$ 26,978
Current, State	14,592	16,686	4,230
Current, Foreign	54,079	62,832	50,368
Total	103,930	132,625	81,576
Deferred, U.S. federal	(28,721)	(61,739)	10,875
Deferred, State	(11,332)	(15,294)	(1,121)
Deferred, Foreign	(644)	104	(2,374)
Total	(40,697)	(76,929)	7,380
Income taxes (benefit)	$ 63,233	$ 55,696	$ 88,956

Income Taxes - Schedule Of Effe

Income Taxes - Schedule Of Effective Tax Rate Differs From The U.S. Federal Statutory Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income tax provision at statutory rate	$ 80,933	$ 81,257	$ 83,243
State taxes, net of federal benefit	6,012	5,118	4,258
Tax impact of foreign operations	(21,435)	(26,881)	(7,693)
Research and development and other credits	(18,917)	(18,055)	(11,843)
Stock-based and other compensation	15,070	12,740	18,002
Other	1,570	1,517	2,989
Income taxes (benefit)	$ 63,233	$ 55,696	$ 88,956

Income Taxes - Schedule Of Tax

Income Taxes - Schedule Of Tax Effects To Deferred Tax Assets And Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Net operating loss carry-forwards	$ 42,849	$ 41,252
Capitalized research and development costs	158,206	95,259
Accrued compensation and benefits	14,068	13,207
Stock-based compensation	10,389	12,829
Deferred revenue	32,244	30,115
Lease liabilities	21,572	23,747
Other accruals and reserves	18,797	18,450
Tax credit carryforwards	28,858	34,187
Depreciation	505	580
Total deferred tax assets before deferred liabilities	327,488	269,626
Valuation allowance	(46,136)	(40,404)
Deferred tax assets, net of valuation allowance	281,352	229,222
Purchased intangibles	(57,350)	(57,219)
Depreciation	(22,278)	(26,516)
Deferred Tax Liabilities, Deferred Expense, Other Capitalized Costs	(12,987)	(13,057)
Deferred Tax Liabilities, Deferred Expense, Reserves and Accruals	(8,153)	(6,651)
Total deferred tax liabilities	(100,768)	(103,443)
Net deferred tax assets	$ 180,584	$ 125,779

Income Taxes - Schedule Of Reco

Income Taxes - Schedule Of Reconciliation Of Beginning And Ending Amount Of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of period	$ 70,814	$ 51,767	$ 42,287
Gross increases related to prior period tax positions	4,816	14,867	8,664
Gross decreases related to prior period tax positions	(10,538)	0	(1,051)
Gross increases related to current period tax positions	10,203	12,595	9,272
Decreases relating to settlements with tax authorities	0	(321)	(3,578)
Reductions due to lapses of statute of limitations	(8,455)	(8,094)	(3,827)
Balance, end of period	$ 66,840	$ 70,814	$ 51,767

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Operating Loss Carryforwards [Line Items]
Income Tax Holiday, Aggregate Dollar Amount	$ 8,500	$ 6,000	$ 8,200
Income Tax Holiday, Income Tax Benefits Per Share	$ 0.14	$ 0.10	$ 0.13
Deferred Tax Assets, Operating Loss Carryforwards	$ 42,849	$ 41,252
Deferred Tax Assets, Tax Credit Carryforwards	28,858	34,187
Valuation Allowance, Deferred Tax Asset, Change in Amount	5,700	7,800
Unrecognized Tax Benefits	66,840	70,814	$ 51,767	$ 42,287
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	43,200	39,200	34,300
Unrecognized Tax Benefits, Period Increase (Decrease)	(1,500)	1,400	$ (1,000)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	2,900	$ 4,400
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carry-forwards, net	63,400
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	300
Deferred Tax Assets, Tax Credit Carryforwards	3,100
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carry-forwards, net	52,000
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	33,300
Deferred Tax Assets, Operating Loss Carryforwards	85,300
Deferred Tax Assets, Tax Credit Carryforwards	7,800
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carry-forwards, net	253,100
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	195,300
Deferred Tax Assets, Operating Loss Carryforwards	448,400
Deferred Tax Assets, Tax Credit Carryforwards	29,500
Deferred Tax Assets, Tax Credit Carryforwards, Subject to Expiration	$ 3,900

Shareholders' Equity - Class of

Shareholders' Equity - Class of Treasury Stock (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 31, 2021	Jun. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Equity, Class of Treasury Stock [Line Items]
Treasury Stock Acquired, Average Cost Per Share	$ 194.91	$ 199.90	$ 191.47	$ 199.90	$ 125.10
Stock Repurchased and Retired During Period, Value			$ 500,023	$ 500,000	$ 100,016
October 26, 2010 Program [Member]
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased and Retired During Period, Shares			2,611	2,501	799

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended	12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Jul. 25, 2022	Feb. 03, 2021	Oct. 31, 2018
Common Stock Repurchase [Line Items]
Accelerated Share Repurchases, Settlement (Payment) or Receipt		$ 400						$ 500
Treasury Stock Acquired, Average Cost Per Share		$ 194.91	$ 199.90	$ 191.47	$ 199.90	$ 125.10
Accelerated Share Repurchases, Cash or Stock Settlement	449,049	2.1 million	2.5 million
Adjustments To Additional Paid In Capital, Equity Forward Contract	$ 100
Stock Repurchase Program, Remaining Authorized Repurchase Amount				$ 1,272
October Twenty Six Two Thousand Ten Program [Member]
Common Stock Repurchase [Line Items]
Stock Repurchase Program, Authorized Amount							$ 1,000		$ 5,400

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions (Details)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Fair Value Assumptions
Expected dividend	0%	0%	0%
Expected term	6 months	6 months	6 months
Minimum
Fair Value Assumptions
Risk-free interest rate	0.05%	0.07%	1.10%
Expected volatility	26.34%	29.67%	26.32%
Maximum
Fair Value Assumptions
Risk-free interest rate	0.62%	0.13%	1.97%
Expected volatility	31.57%	37.22%	41.94%
Two Thousand Eleven Employee Stock Purchase Plan [Member]
Fair Value Assumptions
Expected term	6 months

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule Of Summary Of Restricted Stock Unit Activity (Details)	12 Months Ended
	Sep. 30, 2022 $ / shares shares
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance	$ 145.89
Weighted Average Grant Date Fair Value, Ending balance	$ 206.13
Performance Shares [Member] | Two Thousand Fourteen Equity Incentive Plan [Member]
Outstanding Restricted Stock Units
Outstanding Stock Units, Beginning balance | shares	230,926
Outstanding Stock Units, Units granted | shares	111,283
Outstanding Stock Units, Units vested | shares	(119,889)
Outstanding Stock Units, Units cancelled | shares	(14,204)
Outstanding Stock Units, Ending balance | shares	208,116
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance	$ 136.47
Weighted Average Grant Date Fair Value, Units granted	200.74
Weighted Average Grant Date Fair Value, Units vested	215.12
Weighted Average Grant Date Fair Value, Units cancelled	151.07
Weighted Average Grant Date Fair Value, Ending balance	$ 169.99
Restricted Stock Units (RSUs) [Member] | Two Thousand Fourteen Equity Incentive Plan [Member]
Outstanding Restricted Stock Units
Outstanding Stock Units, Beginning balance | shares	1,340,548
Outstanding Stock Units, Units granted | shares	1,118,854
Outstanding Stock Units, Units vested | shares	(1,122,583)
Outstanding Stock Units, Units cancelled | shares	(199,200)
Outstanding Stock Units, Ending balance | shares	1,137,619
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance	$ 141.90
Weighted Average Grant Date Fair Value, Units granted	206.45
Weighted Average Grant Date Fair Value, Units vested	188.04
Weighted Average Grant Date Fair Value, Units cancelled	170.35
Weighted Average Grant Date Fair Value, Ending balance	$ 184.59

Stock-Based Compensation - Sc_3

Stock-Based Compensation - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions (Details) - $ / shares	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 months	6 months	6 months
Expected dividend	0%	0%	0%
Tranche 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair Value, Per Share	$ 283.35
Expected term	10 months 28 days
Risk-free interest rate	0.13%
Expected dividend	0%
Tranche 1 [Member] | F5 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	26.21%
Tranche 1 [Member] | Index Members [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	27.27%
Tranche 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair Value, Per Share	$ 302.53
Expected term	1 year 10 months 28 days
Risk-free interest rate	0.47%
Expected dividend	0%
Tranche 2 [Member] | F5 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	35.13%
Tranche 2 [Member] | Index Members [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	42.87%
Tranche 3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair Value, Per Share	$ 308.76
Expected term	2 years 10 months 28 days
Risk-free interest rate	0.76%
Expected dividend	0%
Tranche 3 [Member] | F5 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	32.54%
Tranche 3 [Member] | Index Members [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	38.24%

Stock-Based Compensation - Sc_4

Stock-Based Compensation - Schedule of Nonvested Restricted Stock Units Activity (Details) - shares	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years	2 years	2 years
Annual Equity Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Annual Performance Stock Grant Vests In Equal Quarterly Increments	50%
Percentage Of Annual Performance Stock Grant Based On Achieving Specified Annual Performance Goals	50%
Annual Equity Program [Member] | CEO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Annual Performance Stock Grant Vests In Equal Quarterly Increments	40%
Percentage Of Annual Performance Stock Grant Based On Achieving Specified Annual Performance Goals	60%
Annual Equity Program [Member] | November 1, 2021 | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options, Grants in Period	160,384
Award vesting period	3 years
Annual Equity Program [Member] | November 2, 2020 | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options, Grants in Period	257,568
Award vesting period	3 years
Annual Equity Program [Member] | November 1, 2019 [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options, Grants in Period	228,616
Award vesting period	3 years
Annual Equity Program [Member] | November 1, 2018 [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options, Grants in Period	144,066
Award vesting period	3 years

Stock-Based Compensation - Sc_5

Stock-Based Compensation - Schedule Of Stock Option Activity (Details)	12 Months Ended
	Sep. 30, 2022 $ / shares shares
Number of Shares
Number of Shares, Beginning balance | shares	324,624
Number of Shares, Options granted | shares	0
Number of Shares, Options exercised | shares	(143,128)
Number of Shares, Options cancelled | shares	(16,700)
Number of Shares, Ending balance | shares	164,796
Weighted Average Exercise Price per Share
Weighted Average Exercise Price per Share, Beginning balance | $ / shares	$ 30.83
Weighted Average Exercise Price per Share, Options granted | $ / shares	0
Weighted Average Exercise Price per Share, Options exercised | $ / shares	25.24
Weighted Average Exercise Price per Share, Options cancelled | $ / shares	53.98
Weighted Average Exercise Price per Share, Ending balance | $ / shares	$ 33.34

Stock-Based Compensation - Sc_6

Stock-Based Compensation - Schedule Of Outstanding Stock Options Currently Exercisable, Vested And Expected To Vest (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Stock options outstanding	164,796	324,624
Stock options outstanding, Weighted Average Remaining Contractual Life (in Years)	6 years 5 months 12 days
Stock options outstanding, Weighted Average Exercise Price per Share	$ 33.34	$ 30.83
Stock options outstanding, Aggregate Intrinsic Value	$ 18,357
Exercisable, Number of Shares	127,072
Exercisable, Weighted Average Remaining Contractual Life (in Years)	6 years 2 months 12 days
Exercisable, Weighted Average Exercise Price per Share	$ 30.76
Exercisable, Aggregate Intrinsic Value	$ 14,482
Vested and expected to vest, Number of Shares	162,713
Vested and expected to vest, Weighted Average Remaining Contractual Life (in Years)	6 years 5 months 1 day
Vested and expected to vest, Weighted Average Exercise Price per Share	$ 33.20
Vested and expected to vest, Aggregate Intrinsic Value	$ 18,147

Stock-Based Compensation - Sc_7

Stock-Based Compensation - Schedule Of Equity Based Awards (Including Stock Options And Restricted Stock Units (Details) - Equity Based Awards [Member]	12 Months Ended
	Sep. 30, 2022 shares
Awards Available for Grant
Awards Available for Grant, Beginning balance	1,988,410
Awards Available for Grant, Granted	(1,255,975)
Awards Available for Grant, Cancelled	327,201
Additional shares reserved (terminated), net	1,013,142
Awards Available for Grant, Ending balance	2,072,778

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - USD ($)		12 Months Ended
	Oct. 31, 2022	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Oct. 01, 2021	Jan. 22, 2021	Jan. 24, 2020	May 08, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense		$ 249,200,000	$ 243,300,000	$ 201,900,000
Share-based Payment Arrangement, Expense, Tax Benefit		47,300,000	$ 44,100,000	$ 37,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 196,500,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years
Expected term		6 months	6 months	6 months
Weighted Average Grant Date Fair Value		$ 206.13	$ 145.89	$ 137.84
Fair market value of restricted stock vested		$ 262,400,000	$ 261,900,000	$ 138,400,000
Total intrinsic value of options exercised		$ 25,600,000	$ 25,600,000	$ 11,400,000
Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options, Grants in Period	1,321,304
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		2 years	2 years	2 years
Two Thousand Eleven Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance		10,000,000
Percentage of base compensation for which employees can acquire shares of common stock		15%
Maximum shares allowed for purchase by employee in period		10,000
Maximum aggregate fair value of stock that an employee may purchase		$ 25,000
Expected term		6 months
Percentage of common stock lesser of the fair market value		85%
Number of Shares Authorized		945,136
Nginx Acquisition Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance								183,061
Vesting rate of stock options and awards upon certain changes in ownership control		50%
Nginx Acquisition Equity Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock units		20,923
Nginx, Inc. 2011 Share Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance								302,634
Nginx, Inc. 2011 Share Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock units		2,997
Nginx, Inc. 2011 Share Plan [Member] | Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for purchase under stock option plan		16,295
Shape Acquisition Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance							450,000
Vesting rate of stock options and awards upon certain changes in ownership control		50%
Shape Acquisition Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock units		83,164
Shape 2011 Share Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance							501,085
Shape 2011 Share Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock units		1,443
Shape 2011 Share Plan [Member] | Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for purchase under stock option plan		79,508
Volterra Acquisition Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance						140,000
Vesting rate of stock options and awards upon certain changes in ownership control		50%
Volterra Acquisition Equity Incentive Plan | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock units		103,880
Volterra 2017 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance						261,696
Volterra 2017 Stock Plan | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock units		17,934
Volterra 2017 Stock Plan | Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for purchase under stock option plan		68,993
Threat Stack Acquisition Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance					35,000
Vesting rate of stock options and awards upon certain changes in ownership control		50%
Threat Stack Acquisition Equity Incentive Plan | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Issued in Period		25,838
Outstanding stock units		23,534
Two Thousand Fourteen Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance		23,380,000
Vesting rate of stock options and awards upon certain changes in ownership control		50%
Number of Shares Authorized		2,072,778
Two Thousand Fourteen Equity Incentive Plan [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Issued in Period		111,283
Outstanding stock units		208,116	230,926
Weighted Average Grant Date Fair Value		$ 169.99	$ 136.47
Equity Instruments Other than Options, Grants in Period		111,283
Two Thousand Fourteen Equity Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Issued in Period		1,118,854
Outstanding stock units		1,137,619	1,340,548
Weighted Average Grant Date Fair Value		$ 184.59	$ 141.90
Equity Instruments Other than Options, Grants in Period		1,118,854

Net Income Per Share (Details)

Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Net Income Per Share [Abstract]
Net income	$ 322,160	$ 331,241	$ 307,441
Weighted average shares - basic (shares)	60,274	60,707	60,911
Weighted Average Number Diluted Shares Outstanding Adjustment	823	1,350	467
Weighted Average Number of Shares Outstanding, Diluted	61,097	62,057	61,378
Net income per share - basic (USD per share)	$ 5.34	$ 5.46	$ 5.05
Net income per share - diluted (USD per share)	$ 5.27	$ 5.34	$ 5.01

Restructuring Charges (Details)

Restructuring Charges (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2021 USD ($) employee	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Restructuring and Related Activities [Abstract]
Number of Employees in Reduction of Force Program | employee	70
Restructuring charges | $	$ 7,900	$ 7,909	$ 0	$ 7,800

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Contributions by the Company to the plan	$ 14	$ 13.2	$ 11.3
Employer contribution, vesting period	4 years	4 years	4 years

Segment Information (Details)

Segment Information (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2022 USD ($) geographic_region segment	Sep. 30, 2021 USD ($) segment geographic_region	Sep. 30, 2020 USD ($) segment geographic_region
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment	1	1	1
Number of Geographic Regions | geographic_region	3	3	3
Net revenues	$ 2,695,845	$ 2,603,416	$ 2,350,822
Property and equipment, net	168,182	191,164
Product [Member]
Segment Reporting Information [Line Items]
Net revenues	1,317,117	1,247,084	1,025,856
Product [Member] | Systems
Segment Reporting Information [Line Items]
Net revenues	651,902	748,192	668,313
Product [Member] | Software
Segment Reporting Information [Line Items]
Net revenues	665,215	498,892	357,543
United States [Member]
Segment Reporting Information [Line Items]
Net revenues	1,487,144	1,365,625	1,221,190
Property and equipment, net	134,699	153,030
Other Americas [Member]
Segment Reporting Information [Line Items]
Net revenues	85,711	92,111	95,878
Americas [Member]
Segment Reporting Information [Line Items]
Net revenues	1,572,855	1,457,736	1,317,068
EMEA [Member]
Segment Reporting Information [Line Items]
Net revenues	634,759	667,219	593,307
Property and equipment, net	17,376	20,526
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net revenues	488,231	478,461	$ 440,447
Other International Countries [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	$ 16,107	$ 17,608
Customer One [Member] | Geographic Concentration Risk [Member] | Revenue Benchmark [Member]
Segment Reporting Information [Line Items]
Concentration risk percentage	20%	19.20%	16.70%
Customer One [Member] | Geographic Concentration Risk [Member] | Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Concentration risk percentage	12.90%	12.60%
Customer Two [Member] | Geographic Concentration Risk [Member] | Revenue Benchmark [Member]
Segment Reporting Information [Line Items]
Concentration risk percentage	13.40%	11.10%	0%
Customer Two [Member] | Geographic Concentration Risk [Member] | Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Concentration risk percentage	12.60%	11.90%
Customer Three [Member] | Geographic Concentration Risk [Member] | Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Concentration risk percentage	16.20%	11.50%

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event [Member] $ in Millions	Oct. 27, 2022 USD ($)
Subsequent Event [Line Items]
Long-Term Purchase Commitment, Annual Amount	$ 10
Long-Term Purchase Commitment, Amount	$ 40
Long-Term Purchase Commitment, Period	4 years