F5 (FFIV) 10-Q 5 Feb 21 2021 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Dec. 31, 2020	Jan. 29, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	000-26041
Entity Registrant Name	F5 NETWORKS, 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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		61,650,819
Entity Central Index Key	0001048695
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Current assets
Cash and cash equivalents	$ 1,026,829	$ 849,556
Short-term investments	346,515	360,333
Accounts Receivable, net of allowances of $3,356 and $3,105	346,670	296,183
Inventories	26,455	27,898
Other current assets	283,341	259,506
Total current assets	2,029,810	1,793,476
Property and equipment, net	215,649	229,239
Operating lease right-of-use assets	286,044	300,680
Long-term investments	88,753	102,939
Deferred tax assets	47,236	45,173
Goodwill	1,863,892	1,858,966
Other assets, net	367,955	347,447
Total assets	4,899,339	4,677,920
Current liabilities
Accounts payable	57,542	64,472
Accrued liabilities	305,792	321,398
Deferred revenue	936,640	883,134
Current portion of long-term debt	19,275	19,275
Total current liabilities	1,319,249	1,288,279
Deferred tax liabilities	1,965	602
Deferred revenue, long-term	422,185	389,498
Operating lease liabilities, long-term	328,468	338,715
Long-term debt	364,229	369,047
Other long-term liabilities	61,653	59,511
Total long-term liabilities	1,178,500	1,157,373
Commitments and contingencies (Note 9)
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, 61,632 and 61,099 shares issued and outstanding	386,236	305,453
Accumulated other comprehensive loss	(17,855)	(18,716)
Retained earnings	2,033,209	1,945,531
Total shareholders' equity	2,401,590	2,232,268
Total liabilities and shareholders' equity	$ 4,899,339	$ 4,677,920

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Statement of Financial Position [Abstract]
Accounts receivable, allowances	$ 3,356	$ 3,105
Preferred stock, par value (dollars per share)	$ 0	$ 0
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value (dollars per share)	$ 0	$ 0
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	61,632,000	61,099,000

Consolidated Income Statements

Consolidated Income Statements - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Net revenues
Revenue from contract with customer, excluding assessed tax	$ 624,617	$ 569,305
Cost of net revenues
Cost of net revenues	114,979	88,642
Gross profit	509,638	480,663
Operating expenses
Sales and marketing	214,546	195,519
Research and development	114,191	96,005
General and administrative	63,153	59,004
Restructuring charges	0	7,800
Total	391,890	358,328
Income from operations	117,748	122,335
Other (loss) income, net	(683)	5,220
Income before income taxes	117,065	127,555
Provision for income taxes	29,387	29,028
Net income	$ 87,678	$ 98,527
Net income per share — basic (dollars per share)	$ 1.43	$ 1.62
Weighted average shares — basic (shares)	61,440	60,649
Net income per share — diluted (dollars per share)	$ 1.41	$ 1.62
Weighted average shares — diluted (shares)	62,282	60,815
Product
Net revenues
Revenue from contract with customer, excluding assessed tax	$ 288,045	$ 234,536
Cost of net revenues
Cost of net revenues	67,038	42,118
Service
Net revenues
Revenue from contract with customer, excluding assessed tax	336,572	334,769
Cost of net revenues
Cost of net revenues	$ 47,941	$ 46,524

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 87,678	$ 98,527
Other comprehensive income:
Foreign currency translation adjustment	1,278	634
Available-for-sale securities:
Unrealized (losses) gains on securities, net of taxes of $(50) and $28 for the three months ended December 31, 2020 and 2019, respectively	(420)	189
Reclassification adjustment for realized gains (losses) included in net income, net of taxes of $0 and $2 for the three months ended December 31, 2020 and 2019, respectively	3	(9)
Net change in unrealized (losses) gains on available-for-sale securities, net of tax	(417)	180
Total other comprehensive income	861	814
Comprehensive income	$ 88,539	$ 99,341

Consolidated Statements Of Co_2

Consolidated Statements Of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Tax effect of unrealized gain (loss) on securities	$ (50)	$ 28
Tax effect of reclassification adjustment for realized (gains) losses	$ 0	$ 2

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity Statement - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	AOCI Attributable to Parent	Retained Earnings
Beginning Balance (in shares) at Sep. 30, 2019		60,367
Beginning Balance at Sep. 30, 2019	$ 1,761,497	$ 142,597	$ (19,190)	$ 1,638,090
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of employee stock options (in shares)		11
Exercise of employee stock options	290	$ 290
Issuance of stock under employee stock purchase plan (in shares)		169
Issuance of stock under employee stock purchase plan	20,669	$ 20,669
Issuance of restricted stock (in shares)		256
Issuance of restricted stock	0
Cost of Issuance of Treasury Stock	0
Stock-based compensation	47,661	$ 47,661
Net income	98,527			98,527
Other comprehensive income	814		814
Ending Balance ( in shares) at Dec. 31, 2019		60,803
Ending Balance at Dec. 31, 2019	$ 1,929,458	$ 211,217	(18,376)	1,736,617
Beginning Balance (in shares) at Sep. 30, 2020	61,099	61,099
Beginning Balance at Sep. 30, 2020	$ 2,232,268	$ 305,453	(18,716)	1,945,531
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of employee stock options (in shares)		39
Exercise of employee stock options	1,118	$ 1,118
Issuance of stock under employee stock purchase plan (in shares)		231
Issuance of stock under employee stock purchase plan	26,077	$ 26,077
Issuance of restricted stock (in shares)		297
Issuance of restricted stock	0
Cost of Issuance of Treasury Stock, Shares		(34)
Cost of Issuance of Treasury Stock	(4,481)	$ (4,481)
Stock-based compensation	58,069	$ 58,069
Net income	87,678			87,678
Other comprehensive income	$ 861		861
Ending Balance ( in shares) at Dec. 31, 2020	61,632	61,632
Ending Balance at Dec. 31, 2020	$ 2,401,590	$ 386,236	$ (17,855)	$ 2,033,209

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating activities
Net income	$ 87,678	$ 98,527
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	58,069	47,661
Depreciation and amortization	27,660	18,979
Non-cash operating lease costs	9,698	8,703
Deferred income taxes	(694)	(1,714)
Impairment of assets	6,873	0
Other	307	(31)
Changes in operating assets and liabilities (excluding effects of the acquisition of businesses):
Accounts receivable	(54,416)	(32,683)
Inventories	1,443	2,020
Other current assets	(23,250)	(5,494)
Other assets	(26,654)	2,011
Accounts payable and accrued liabilities	(23,925)	(23,606)
Deferred revenue	86,193	39,856
Lease liabilities	(11,619)	(10,217)
Net cash provided by operating activities	137,363	144,012
Investing activities
Purchases of investments	(42,765)	(180,557)
Maturities of investments	69,352	150,697
Sales of investments	0	22,764
Acquisition of businesses, net of cash acquired	(1,247)	0
Purchases of property and equipment	(4,697)	(22,304)
Net cash provided by (used in) investing activities	20,643	(29,400)
Financing activities
Proceeds from the exercise of stock options and purchases of stock under employee stock purchase plan	27,196	20,959
Payments on term debt agreement	(5,000)	0
Cost of Issuance of Treasury Stock	(4,481)	0
Net cash provided by financing activities	17,715	20,959
Net increase in cash, cash equivalents and restricted cash	175,721	135,571
Effect of exchange rate changes on cash, cash equivalents and restricted cash	1,655	820
Cash, cash equivalents and restricted cash, beginning of period	852,826	602,254
Cash, cash equivalents and restricted cash, end of period	1,030,202	738,645
Supplemental disclosures of cash flow information
Cash paid for amounts included in the measurement of operating lease liabilities	15,032	12,707
Cash paid for interest on long-term debt	1,370	0
Supplemental disclosures of non-cash activities
Right-of-use assets obtained in exchange for lease obligations	$ 1,614	$ 394,315

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Description of Business F5 Networks, Inc. (the "Company") is a leading provider of multi-cloud application services 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. Basis of Presentation The year-end consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America ("GAAP"). In the opinion of management, the unaudited consolidated financial statements reflect all adjustments, consisting only of normal recurring adjustments, necessary for their fair statement in conformity with accounting principles generally accepted in the United States of America. Certain information and footnote disclosures normally included in annual financial statements have been condensed or omitted in accordance with the rules and regulations of the Securities and Exchange Commission ("SEC"). The information included in this Form 10-Q should be read in conjunction with Management’s Discussion and Analysis of Financial Condition and Results of Operations and financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2020. In December 2019, a novel strain of coronavirus (“COVID-19“) was first identified, and in March 2020, the World Health Organization categorized COVID-19 as a pandemic. The Company assessed the impact that COVID-19 had on its results of operations, including, but not limited to an assessment of its allowance for current expected credit losses, the carrying value of short-term and long-term investments, the carrying value of goodwill and other long-lived assets, and the impact to revenue recognition and cost of revenues. The Company is actively monitoring the impact to the results of its business operations, and may make decisions required by federal, state or local authorities, or that are determined to be in the best interests of its employees, customers, partners, suppliers and stockholders. As of the filing date, the extent to which the COVID-19 pandemic may impact the Company’s financial condition or results of operations remains uncertain. Recently Adopted Accounting Standards In August 2018, the FASB issued ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40) (ASU 2018-15), which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software, and hosting arrangements that include an internal-use software license. The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this update. The Company adopted this new standard prospectively on October 1, 2020. The adoption of this standard did not have a material impact to the Company’s consolidated financial statements or disclosures. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), which modifies the accounting for credit losses for most financial assets and requires the use of an expected loss model, replacing the currently used incurred loss method. Under this model, entities will be required to estimate the lifetime expected credit loss on such instruments and record an allowance to offset the amortized cost basis of the financial asset, resulting in a net presentation of the amount expected to be collected on the financial asset. The Company adopted this new standard on October 1, 2020 using the modified retrospective approach. The adoption of this standard did not have a material impact on the Company’s condensed consolidated financial statements. The following accounting policies were updated as a result of the adoption of this standard. Investments The Company classifies its investment securities as available-for-sale. Investment securities, 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 and impairments due to credit losses, in which the fair value of a security is below its amortized cost and management’s intent is to sell the impaired security prior to its recovery, are included in other income (expense). An allowance for credit losses for the excess of amortized cost over the expected cash flows is recorded in other income, net in the Company's consolidated income statements. The cost of investments for purposes of computing realized and unrealized gains and losses is based on the specific identification method. Investments in securities 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. Investments with maturities of greater than one year are classified as long-term investments. 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 the three months ended December 31, 2020 and 2019, the allowance for credit losses activity was not significant. There have been no additional changes to the Company's significant accounting policies as of and for the three months ended December 31, 2020.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	3 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contracts 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 three months ended December 31, 2020 and 2019 (in thousands): Three months ended 2020 2019 Balance, beginning of period $ 70,396 $ 59,446 Additional capitalized contract acquisition costs deferred 9,725 7,412 Amortization of capitalized contract acquisition costs (8,152) (8,705) Balance, end of period $ 71,969 $ 58,153 Amortization of capitalized contract acquisition costs was $8.2 million and $8.7 million for the three months ended December 31, 2020 and 2019, 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. The Company records assets for amounts related to performance obligations that are satisfied but not yet billed and/or collected, in addition to contracts that have started, but not yet been fully billed. These assets are recorded as contract assets rather than receivables when receipt of the consideration is conditional on something other than the passage of time. Liabilities are recorded for amounts that are collected in advance of the satisfaction of performance obligations. These liabilities are classified as current and non-current deferred revenue. The table below shows significant movements in contract assets (current and noncurrent) for the three months ended December 31, 2020 and 2019 (in thousands): Three months ended 2020 2019 Balance, beginning of period $ 200,472 $ 132,492 Revenue recognized during period but not yet billed 18,316 3,407 Contract asset additions 55,834 12,930 Contract assets reclassified to accounts receivable (28,818) (13,584) Balance, end of period $ 245,804 $ 135,245 As of December 31, 2020, contract assets that are expected to be reclassified to receivables within the next 12 months are included in other current assets, with those expected to be transferred to receivables in more than 12 months included in other assets. There were no impairments of contract assets during the three months ended December 31, 2020 and 2019. The table below shows significant movements in the deferred revenue balances (current and noncurrent) for the three months ended December 31, 2020 and 2019 (in thousands): Three months ended 2020 2019 Balance, beginning of period $ 1,272,632 $ 1,198,116 Amounts billed but not recognized as revenues 421,918 346,132 Revenues recognized related to the opening balance of deferred revenue (335,725) (306,275) Balance, end of period $ 1,358,825 $ 1,237,973 The Company's contract assets and liabilities are reported in a net position on a contract by contract basis at the end of each reporting period. 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. As of December 31, 2020, the total non-cancelable remaining performance obligations under the Company's contracts with customers was approximately $1.4 billion and the Company expects to recognize revenues on approximately 68.9% of these remaining performance obligations over the next 12 months, 18.9% in year two, and the remaining balance thereafter. See Note 12, Segment Information, for disaggregated revenue by significant customer and geographic region, as well as disaggregated product revenue by systems and software.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements In 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. The Company's financial assets measured at fair value on a recurring basis subject to the disclosure requirements at December 31, 2020, were as follows (in thousands): Fair Value Measurements at Reporting Date Using Quoted Prices in Active Markets for Identical Securities Significant Other Significant Fair Value at Cash equivalents $ 286,495 $ 208,406 $ — $ 494,901 Short-term investments Available-for-sale securities — corporate bonds and notes — 179,694 — 179,694 Available-for-sale securities — municipal bonds and notes — 2,916 — 2,916 Available-for-sale securities — U.S. government securities — 116,526 — 116,526 Available-for-sale securities — U.S. government agency securities — 47,379 — 47,379 Long-term investments Available-for-sale securities — corporate bonds and notes — 72,173 — 72,173 Available-for-sale securities — U.S. government agency securities — 16,580 — 16,580 Total $ 286,495 $ 643,674 $ — $ 930,169 The Company's financial assets measured at fair value on a recurring basis subject to the disclosure requirements at September 30, 2020, were as follows (in thousands): Fair Value Measurements at Reporting Date Using Quoted Prices in Active Markets Significant Significant Fair Value at Cash equivalents $ 43,553 $ 207,417 $ — $ 250,970 Short-term investments Available-for-sale securities — corporate bonds and notes — 189,662 — 189,662 Available-for-sale securities — municipal bonds and notes — 6,146 — 6,146 Available-for-sale securities — U.S. government securities — 117,374 — 117,374 Available-for-sale securities — U.S. government agency securities — 47,151 — 47,151 Long-term investments Available-for-sale securities — corporate bonds and notes — 102,939 — 102,939 Total $ 43,553 $ 670,689 $ — $ 714,242 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. 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 and intangible assets 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 long-lived assets for impairment whenever events or changes in circumstances indicate its carrying amount may not be recoverable. Included in the Company’s impairment considerations for non-financial assets and liabilities in the current quarter were the

Short-Term and Long-Term Invest

Short-Term and Long-Term Investments	3 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Short-Term and Long-Term Investments	Short-Term and Long-Term Investments Short-term investments consist of the following (in thousands): December 31, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 179,159 $ 540 $ (5) $ 179,694 Municipal bonds and notes 2,916 — — 2,916 U.S. government securities 116,515 15 (4) 116,526 U.S. government agency securities 47,377 3 (1) 47,379 $ 345,967 $ 558 $ (10) $ 346,515 September 30, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 188,932 $ 736 $ (6) $ 189,662 Municipal bonds and notes 6,143 3 — 6,146 U.S. government securities 117,363 14 (3) 117,374 U.S. government agency securities 47,148 3 — 47,151 $ 359,586 $ 756 $ (9) $ 360,333 Long-term investments consist of the following (in thousands): December 31, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 71,711 $ 462 $ — $ 72,173 U.S. government agency securities 16,580 — — 16,580 $ 88,291 $ 462 $ — $ 88,753 September 30, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 102,206 $ 756 $ (23) $ 102,939 $ 102,206 $ 756 $ (23) $ 102,939 Interest income from investments was $1.1 million and $5.6 million for the three months ended December 31, 2020 and 2019, respectively. Interest income is included in other income, net on the Company's consolidated income statements. The following table summarizes investments that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for more than 12 months as of December 31, 2020 (in thousands): Less Than 12 Months 12 Months or Greater Total December 31, 2020 Fair Value Gross Fair Value Gross Fair Value Gross Corporate bonds and notes $ 26,703 $ (5) $ — $ — $ 26,703 $ (5) U.S. government securities 29,053 (4) — — 29,053 (4) U.S. government agency securities 33,127 (1) — — 33,127 (1) Total $ 88,883 $ (10) $ — $ — $ 88,883 $ (10) The following table summarizes investments that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for more than 12 months as of September 30, 2020 (in thousands): Less Than 12 Months 12 Months or Greater Total September 30, 2020 Fair Value Gross Fair Value Gross Fair Value Gross Corporate bonds and notes $ 43,492 $ (28) $ 5,006 $ (1) $ 48,498 $ (29) U.S. government securities 41,812 (3) — — 41,812 (3) Total $ 85,304 $ (31) $ 5,006 $ (1) $ 90,310 $ (32) The Company invests in securities that are rated investment grade. Gross unrealized losses were not material for the three months ended December 31, 2020. The Company reviews the individual securities in its portfolio to determine whether a decline in a security's fair value below the amortized cost basis is other-than-temporary. The Company determined that as of December 31, 2020, there were no investments in its portfolio that were other-than-temporarily impaired.

Business Combinations

Business Combinations	3 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Business Combinations	Business Combinations Fiscal Year 2020 Acquisition of Shape Security, Inc. On December 19, 2019, the Company entered into a Merger Agreement (the "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. Pursuant to the 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 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 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 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 $ 53,934 Fair value of tangible assets: Accounts receivable 21,077 Deferred tax assets 24,619 Operating lease right-of-use assets 29,644 Other tangible assets 22,571 Identifiable intangible assets: Developed technologies 120,000 7 years Customer relationships 21,000 4 years Trade name 9,500 5 years Goodwill 804,537 Total assets acquired $ 1,106,882 Liabilities assumed Deferred revenue $ (39,000) Operating lease liabilities (30,773) Other assumed liabilities (18,571) Total liabilities assumed $ (88,344) Net assets acquired $ 1,018,538 The measurement period for the Shape acquisition will lapse in the second quarter of fiscal 2021. In the first quarter of fiscal 2021, the Company increased the carrying amount of goodwill by $4.9 million to reflect an adjustment to consideration exchanged for the purchase of Shape within the post-close measurement period. No other financial statement amounts were affected by this adjustment. The adjustment was not material to the current period or any of the previous period financial statements. The developed technology intangible asset will be 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 will be 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. Since the Shape acquisition was completed on January 24, 2020, the F5 and Shape teams have been executing a plan to integrate ongoing operations. The pro forma financial information, as well as the revenue and earnings generated by Shape, were not considered material to the Company's operations.

Balance Sheet Details

Balance Sheet Details	3 Months Ended
	Dec. 31, 2020
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): December 31, September 30, Cash and cash equivalents $ 1,026,829 $ 849,556 Restricted cash included in other assets, net 3,373 3,270 Total cash, cash equivalents and restricted cash $ 1,030,202 $ 852,826 Inventories Inventories consist of the following (in thousands): December 31, September 30, Finished goods $ 15,839 $ 17,096 Raw materials 10,616 10,802 $ 26,455 $ 27,898 Other Current Assets Other current assets consist of the following (in thousands): December 31, September 30, Contract assets $ 163,546 $ 138,096 Prepaid expenses 59,232 47,197 Capitalized contract acquisition costs 30,687 29,650 Other 29,876 44,563 $ 283,341 $ 259,506 Other Assets Other assets, net consist of the following (in thousands): December 31, September 30, Intangible assets $ 223,371 $ 225,900 Contract assets 82,258 62,377 Capitalized contract acquisition costs 41,282 40,746 Other 21,044 18,424 $ 367,955 $ 347,447 Accrued Liabilities Accrued liabilities consist of the following (in thousands): December 31, September 30, Payroll and benefits $ 141,378 $ 169,708 Operating lease liabilities, current 46,763 46,010 Income and other tax accruals 39,760 33,048 Other 77,891 72,632 $ 305,792 $ 321,398 Other Long-term Liabilities Other long-term liabilities consist of the following (in thousands): December 31, September 30, Income taxes payable $ 52,523 $ 49,846 Other 9,130 9,665 $ 61,653 $ 59,511

Debt Facilities

Debt Facilities	3 Months Ended
	Dec. 31, 2020
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 December 31, 2020, 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 December 31, 2020, the Company was in compliance with all covenants. As of December 31, 2020, $385.0 million of principal amount under the Term Loan Facility was outstanding, excluding unamortized debt issuance costs of $1.5 million. The weighted average interest rate on the principal amount under the Term Loan Facility outstanding balance was 2.106% for the period ending December 31, 2020. The following table presents the scheduled principal maturities as of December 31, 2020 (in thousands): Fiscal Years Ending September 30: Amount 2021 (remainder) $ 15,000 2022 20,000 2023 350,000 Total $ 385,000 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 the three months ended December 31, 2020 were not material.

Leases

Leases	3 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	Leases During the first quarter of fiscal 2020, the Company adopted ASU 2016-02, Leases (Topic 842) (the "Leasing Standard") using the transition method provided in ASU 2018-11, Leases (Topic 842): Targeted Improvements . The impact of adopting the Leasing Standard resulted in the recognition of right-of-use assets and lease liabilities of $304.8 million and $386.4 million, respectively, on October 1, 2019, the date of adoption. 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 has concluded that the renewal option is not yet likely to be exercised. 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 three months ended December 31, 2020 and 2019 were as follows (in thousands): Three months ended 2020 2019 Operating lease expense $ 12,181 $ 11,318 Short-term lease expense 986 814 Variable lease expense 7,026 5,839 Total lease expense $ 20,193 $ 17,971 Variable lease expense primarily consists of common area maintenance and parking expenses. The Company executed two sublease contracts that commenced during the first quarter of fiscal year 2020. Supplemental balance sheet information related to the Company's operating leases was as follows (in thousands, except lease term and discount rate): December 31, 2020 September 30, 2020 Operating lease right-of-use assets, net $ 286,044 $ 300,680 Operating lease liabilities, current 1 46,763 46,010 Operating lease liabilities, long-term 328,468 338,715 Total operating lease liabilities $ 375,231 $ 384,725 Weighted average remaining lease term (in years) 10.1 10.2 Weighted average discount rate 2.59 % 2.58 % (1) Current portion of operating lease liabilities is included in accrued liabilities on the Company's consolidated balance sheets. As of December 31, 2020, the future operating lease payments for each of the next five years and thereafter is as follows (in thousands): Fiscal Years Ending September 30: Operating Lease 2021 (remainder) $ 41,075 2022 57,598 2023 44,656 2024 39,995 2025 33,588 2026 26,705 Thereafter 191,236 Total lease payments 434,853 Less: imputed interest (59,622) Total lease liabilities $ 375,231 Operating lease liabilities above do not include sublease income. As of December 31, 2020, the Company expects to receive sublease income of approximately $9.1 million, which consists of $3.3 million to be received for the remainder of fiscal 2021 and $5.8 million to be received over the two fiscal years thereafter. In the first quarter of fiscal 2021, the Company 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.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies 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 certain other employees, 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 generally 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. Accrued warranty costs as of December 31, 2020 and September 30, 2020 were not material. Commitments As of December 31, 2020, the Company's principal commitments consisted of borrowings under the Term Loan Facility and obligations outstanding under operating leases. Refer to Note 7 for the scheduled principal maturities of the Term Loan Facility as of December 31, 2020. The Company leases its facilities under operating leases that expire at various dates through 2033. There have been no material changes in the Company's lease obligations compared to those discussed in Note 8 to its annual consolidated financial statements. The Company currently has arrangements with contract manufacturers and other suppliers for the manufacturing of its products. The arrangement with the primary contract manufacturer allows them to procure component inventory on the Company's behalf based on a rolling production forecast provided by the Company. The Company is obligated to the purchase of component inventory that the contract manufacturer procures in accordance with the forecast, unless it gives notice of order cancellation in advance of applicable lead times. There have been no material changes in the Company's inventory purchase obligations compared to those discussed in Note 13 to its annual consolidated financial statements. Legal Proceedings 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. The Company and the other defendants have filed motions to dismiss all claims asserted against them in the lawsuit. In addition to the above matter, 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 currently to determine the ultimate outcome of these or similar matters or the potential exposure to loss, if any. 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.

Income Taxes

Income Taxes	3 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company's tax provision for interim periods is determined using an estimated annual effective tax rate, adjusted for discrete items in the related period. The effective tax rate was 25.1% and 22.8% for the three months ended December 31, 2020 and 2019, respectively. The increase in the effective tax rate for the three months ended December 31, 2020 as compared to the three months ended December 31, 2019 is primarily due to the tax impact from stock-based compensation and other non-deductible expenses. At December 31, 2020, the Company had $54.3 million of unrecognized tax benefits that, if recognized, would affect the effective tax rate. It is anticipated that the Company’s existing liabilities for unrecognized tax benefits will change within the next twelve months due to audit settlements or the expiration of statutes of limitations. The Company does not expect these changes to be material to the consolidated financial statements. The Company recognizes interest and, if applicable, penalties for any uncertain tax positions as a component of income tax expense.

Net Income Per Share

Net Income Per Share	3 Months Ended
	Dec. 31, 2020
Net Income Per Share [Abstract]
Net Income Per Share	Net Income Per Share Basic 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): Three months ended 2020 2019 Numerator Net income $ 87,678 $ 98,527 Denominator Weighted average shares outstanding — basic 61,440 60,649 Dilutive effect of common shares from stock options and restricted stock units 842 166 Weighted average shares outstanding — diluted 62,282 60,815 Basic net income per share $ 1.43 $ 1.62 Diluted net income per share $ 1.41 $ 1.62 Anti-dilutive stock-based awards excluded from the calculations of diluted earnings per share were not material for the three months ended December 31, 2020 and 2019.

Segment Information

Segment Information	3 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Segment Information	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 services that optimize the security, performance and availability of network applications, servers and storage systems. 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): Three months ended 2020 2019 Americas: United States $ 320,343 $ 275,499 Other 22,793 26,063 Total Americas 343,136 301,562 EMEA 162,084 155,952 Asia Pacific 119,397 111,791 $ 624,617 $ 569,305 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): Three months ended 2020 2019 Net product revenues Systems revenue $ 178,571 $ 169,601 Software revenue 109,474 64,935 Total net product revenue $ 288,045 $ 234,536 The following distributors of the Company's products accounted for more than 10% of total net revenue: Three months ended 2020 2019 Ingram Micro, Inc. 18.1 % 16.5 % Westcon Group, Inc. — 11.0 % Arrow ECS — 10.1 % Synnex Corporation 10.0 % — The Company tracks assets by physical location. Long-lived assets consist of property and equipment, net, and are shown below (in thousands): December 31, September 30, United States $ 178,638 $ 190,509 EMEA 19,405 20,361 Other countries 17,606 18,369 $ 215,649 $ 229,239

Restructuring Charges

Restructuring Charges	3 Months Ended
	Dec. 31, 2020
Restructuring Charges [Abstract]
Restructuring Charges	Restructuring ChargesIn December 2019, 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 75 employees. The Company recorded a restructuring charge of $7.8 million in the first quarter of fiscal 2020. The Company does not expect to record any significant future charges related to the restructuring plan. During the three months ended December 31, 2019, the following activity was recorded (in thousands): Employee Severance, Benefits and Related Costs Accrued expenses, October 1, 2019 $ — Restructuring charges 7,800 Cash payments (5,282) Non-cash items — Accrued expenses, December 31, 2019 $ 2,518

Subsequent Events

Subsequent Events	3 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Acquisition of Volterra, Inc. On January 5, 2021, the Company entered into a Merger Agreement (the “Merger Agreement”) with Volterra, Inc. ("Volterra"), creator of the first universal edge-as-a-service platform. Pursuant to the Merger Agreement, at the effective time of the Merger, the capital stock of Volterra and the vested outstanding and unexercised stock options in Volterra will be cancelled and converted to the right to receive approximately $440 million in cash and $60 million in deferred consideration, subject to certain adjustments and conditions set forth in the Merger Agreement. The unvested stock options and restricted stock units in Volterra held by continuing employees of Volterra will be assumed by F5, on the terms and conditions set forth in the Merger Agreement. The transaction closed on January 22, 2021 with Volterra becoming a wholly-owned subsidiary of F5. During the first quarter of 2021, the Company incurred approximately $2.7 million of acquisition related expenses associated with the Volterra acquisition, which is included within General and Administrative operating expenses in the Company’s Consolidated Income Statement. As a result of limited access to Volterra information required to prepare initial accounting, together with the limited time since the acquisition date and the effort required to conform the financial statements to the Company's practices and policies, the initial accounting for the business combination is incomplete at the time of this filing. As a result, the Company is unable to provide the amounts recognized as of the acquisition date for the major classes of assets acquired and liabilities assumed, pre-acquisition contingencies and goodwill. Share Repurchase Activities 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 and received an initial delivery of shares, which approximates 80 percent of the total number of shares to be repurchased under the ASR agreements. The shares received by the Company were immediately retired. In accordance with the terms of the ASR agreements, the final number of shares to be repurchased and the average price paid per share will be determined upon settlement of the agreements by the end of the third quarter of fiscal 2021. The final number of shares to be repurchased will be based on the volume-weighted average price of the Company’s common stock over the duration of the ASR agreements, less applicable discounts. Upon settlement, the financial institutions may be required to deliver additional shares of common stock to the Company, or under certain conditions, the Company may be required to make a cash payment or deliver shares of common stock, at its election, to the financial institutions. Prior to entering into the ASR agreements, the Company had $1.3 billion remaining authorized under its share repurchase program.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Description of Business	Description of Business F5 Networks, Inc. (the "Company") is a leading provider of multi-cloud application services 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.
Basis of Presentation	Basis of Presentation The year-end consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America ("GAAP"). In the opinion of management, the unaudited consolidated financial statements reflect all adjustments, consisting only of normal recurring adjustments, necessary for their fair statement in conformity with accounting principles generally accepted in the United States of America. Certain information and footnote disclosures normally included in annual financial statements have been condensed or omitted in accordance with the rules and regulations of the Securities and Exchange Commission ("SEC"). The information included in this Form 10-Q should be read in conjunction with Management’s Discussion and Analysis of Financial Condition and Results of Operations and financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2020. In December 2019, a novel strain of coronavirus (“COVID-19“) was first identified, and in March 2020, the World Health Organization categorized COVID-19 as a pandemic. The Company assessed the impact that COVID-19 had on its results of operations, including, but not limited to an assessment of its allowance for current expected credit losses, the carrying value of short-term and long-term investments, the carrying value of goodwill and other long-lived assets, and the impact to revenue recognition and cost of revenues. The Company is actively monitoring the impact to the results of its business operations, and may make decisions required by federal, state or local authorities, or that are determined to be in the best interests of its employees, customers, partners, suppliers and stockholders. As of the filing date, the extent to which the COVID-19 pandemic may impact the Company’s financial condition or results of operations remains uncertain.
Recent Accounting Pronouncements	Recently Adopted Accounting Standards In August 2018, the FASB issued ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40) (ASU 2018-15), which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software, and hosting arrangements that include an internal-use software license. The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this update. The Company adopted this new standard prospectively on October 1, 2020. The adoption of this standard did not have a material impact to the Company’s consolidated financial statements or disclosures. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), which modifies the accounting for credit losses for most financial assets and requires the use of an expected loss model, replacing the currently used incurred loss method. Under this model, entities will be required to estimate the lifetime expected credit loss on such instruments and record an allowance to offset the amortized cost basis of the financial asset, resulting in a net presentation of the amount expected to be collected on the financial asset. The Company adopted this new standard on October 1, 2020 using the modified retrospective approach. The adoption of this standard did not have a material impact on the Company’s condensed consolidated financial statements. The following accounting policies were updated as a result of the adoption of this standard. Investments The Company classifies its investment securities as available-for-sale. Investment securities, 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 and impairments due to credit losses, in which the fair value of a security is below its amortized cost and management’s intent is to sell the impaired security prior to its recovery, are included in other income (expense). An allowance for credit losses for the excess of amortized cost over the expected cash flows is recorded in other income, net in the Company's consolidated income statements. The cost of investments for purposes of computing realized and unrealized gains and losses is based on the specific identification method. Investments in securities 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. Investments with maturities of greater than one year are classified as long-term investments. 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 the three months ended December 31, 2020 and 2019, the allowance for credit losses activity was not significant.

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	3 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Capitalized Contract Cost	The table below shows significant movements in capitalized contract acquisition costs (current and noncurrent) for the three months ended December 31, 2020 and 2019 (in thousands): Three months ended 2020 2019 Balance, beginning of period $ 70,396 $ 59,446 Additional capitalized contract acquisition costs deferred 9,725 7,412 Amortization of capitalized contract acquisition costs (8,152) (8,705) Balance, end of period $ 71,969 $ 58,153
Contract with Customer, Asset and Liability	The table below shows significant movements in contract assets (current and noncurrent) for the three months ended December 31, 2020 and 2019 (in thousands): Three months ended 2020 2019 Balance, beginning of period $ 200,472 $ 132,492 Revenue recognized during period but not yet billed 18,316 3,407 Contract asset additions 55,834 12,930 Contract assets reclassified to accounts receivable (28,818) (13,584) Balance, end of period $ 245,804 $ 135,245 The table below shows significant movements in the deferred revenue balances (current and noncurrent) for the three months ended December 31, 2020 and 2019 (in thousands): Three months ended 2020 2019 Balance, beginning of period $ 1,272,632 $ 1,198,116 Amounts billed but not recognized as revenues 421,918 346,132 Revenues recognized related to the opening balance of deferred revenue (335,725) (306,275) Balance, end of period $ 1,358,825 $ 1,237,973

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Dec. 31, 2020
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 December 31, 2020, were as follows (in thousands): Fair Value Measurements at Reporting Date Using Quoted Prices in Active Markets for Identical Securities Significant Other Significant Fair Value at Cash equivalents $ 286,495 $ 208,406 $ — $ 494,901 Short-term investments Available-for-sale securities — corporate bonds and notes — 179,694 — 179,694 Available-for-sale securities — municipal bonds and notes — 2,916 — 2,916 Available-for-sale securities — U.S. government securities — 116,526 — 116,526 Available-for-sale securities — U.S. government agency securities — 47,379 — 47,379 Long-term investments Available-for-sale securities — corporate bonds and notes — 72,173 — 72,173 Available-for-sale securities — U.S. government agency securities — 16,580 — 16,580 Total $ 286,495 $ 643,674 $ — $ 930,169 The Company's financial assets measured at fair value on a recurring basis subject to the disclosure requirements at September 30, 2020, were as follows (in thousands): Fair Value Measurements at Reporting Date Using Quoted Prices in Active Markets Significant Significant Fair Value at Cash equivalents $ 43,553 $ 207,417 $ — $ 250,970 Short-term investments Available-for-sale securities — corporate bonds and notes — 189,662 — 189,662 Available-for-sale securities — municipal bonds and notes — 6,146 — 6,146 Available-for-sale securities — U.S. government securities — 117,374 — 117,374 Available-for-sale securities — U.S. government agency securities — 47,151 — 47,151 Long-term investments Available-for-sale securities — corporate bonds and notes — 102,939 — 102,939 Total $ 43,553 $ 670,689 $ — $ 714,242

Short-Term and Long-Term Inve_2

Short-Term and Long-Term Investments (Tables)	3 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Schedule of Short-Term and Long-Term Investments	Short-term investments consist of the following (in thousands): December 31, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 179,159 $ 540 $ (5) $ 179,694 Municipal bonds and notes 2,916 — — 2,916 U.S. government securities 116,515 15 (4) 116,526 U.S. government agency securities 47,377 3 (1) 47,379 $ 345,967 $ 558 $ (10) $ 346,515 September 30, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 188,932 $ 736 $ (6) $ 189,662 Municipal bonds and notes 6,143 3 — 6,146 U.S. government securities 117,363 14 (3) 117,374 U.S. government agency securities 47,148 3 — 47,151 $ 359,586 $ 756 $ (9) $ 360,333 Long-term investments consist of the following (in thousands): December 31, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 71,711 $ 462 $ — $ 72,173 U.S. government agency securities 16,580 — — 16,580 $ 88,291 $ 462 $ — $ 88,753 September 30, 2020 Cost or Gross Gross Fair Value Corporate bonds and notes $ 102,206 $ 756 $ (23) $ 102,939 $ 102,206 $ 756 $ (23) $ 102,939
Schedule of Investments That Have Been in a Continuous Unrealized Loss Position	The following table summarizes investments that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for more than 12 months as of December 31, 2020 (in thousands): Less Than 12 Months 12 Months or Greater Total December 31, 2020 Fair Value Gross Fair Value Gross Fair Value Gross Corporate bonds and notes $ 26,703 $ (5) $ — $ — $ 26,703 $ (5) U.S. government securities 29,053 (4) — — 29,053 (4) U.S. government agency securities 33,127 (1) — — 33,127 (1) Total $ 88,883 $ (10) $ — $ — $ 88,883 $ (10) The following table summarizes investments that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for more than 12 months as of September 30, 2020 (in thousands): Less Than 12 Months 12 Months or Greater Total September 30, 2020 Fair Value Gross Fair Value Gross Fair Value Gross Corporate bonds and notes $ 43,492 $ (28) $ 5,006 $ (1) $ 48,498 $ (29) U.S. government securities 41,812 (3) — — 41,812 (3) Total $ 85,304 $ (31) $ 5,006 $ (1) $ 90,310 $ (32)

Business Combinations (Tables)

Business Combinations (Tables)	3 Months Ended
	Dec. 31, 2020
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 Cash, cash equivalents, and restricted cash $ 53,934 Fair value of tangible assets: Accounts receivable 21,077 Deferred tax assets 24,619 Operating lease right-of-use assets 29,644 Other tangible assets 22,571 Identifiable intangible assets: Developed technologies 120,000 7 years Customer relationships 21,000 4 years Trade name 9,500 5 years Goodwill 804,537 Total assets acquired $ 1,106,882 Liabilities assumed Deferred revenue $ (39,000) Operating lease liabilities (30,773) Other assumed liabilities (18,571) Total liabilities assumed $ (88,344) Net assets acquired $ 1,018,538

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	3 Months Ended
	Dec. 31, 2020
Balance Sheet Details [Abstract]
Cash and Cash Equivalents	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): December 31, September 30, Cash and cash equivalents $ 1,026,829 $ 849,556 Restricted cash included in other assets, net 3,373 3,270 Total cash, cash equivalents and restricted cash $ 1,030,202 $ 852,826
Inventories	Inventories consist of the following (in thousands): December 31, September 30, Finished goods $ 15,839 $ 17,096 Raw materials 10,616 10,802 $ 26,455 $ 27,898
Other Current Assets	Other current assets consist of the following (in thousands): December 31, September 30, Contract assets $ 163,546 $ 138,096 Prepaid expenses 59,232 47,197 Capitalized contract acquisition costs 30,687 29,650 Other 29,876 44,563 $ 283,341 $ 259,506
Other Assets, Noncurrent	Other assets, net consist of the following (in thousands): December 31, September 30, Intangible assets $ 223,371 $ 225,900 Contract assets 82,258 62,377 Capitalized contract acquisition costs 41,282 40,746 Other 21,044 18,424 $ 367,955 $ 347,447
Accrued Liabilities	Accrued liabilities consist of the following (in thousands): December 31, September 30, Payroll and benefits $ 141,378 $ 169,708 Operating lease liabilities, current 46,763 46,010 Income and other tax accruals 39,760 33,048 Other 77,891 72,632 $ 305,792 $ 321,398
Noncurrent Liabilities	Other long-term liabilities consist of the following (in thousands): December 31, September 30, Income taxes payable $ 52,523 $ 49,846 Other 9,130 9,665 $ 61,653 $ 59,511

Debt Facilities (Tables)

Debt Facilities (Tables)	3 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of Maturities of Long-term Debt	The following table presents the scheduled principal maturities as of December 31, 2020 (in thousands): Fiscal Years Ending September 30: Amount 2021 (remainder) $ 15,000 2022 20,000 2023 350,000 Total $ 385,000

Leases (Tables)

Leases (Tables)	3 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lease, Cost	The components of the Company's operating lease expenses for the three months ended December 31, 2020 and 2019 were as follows (in thousands): Three months ended 2020 2019 Operating lease expense $ 12,181 $ 11,318 Short-term lease expense 986 814 Variable lease expense 7,026 5,839 Total lease expense $ 20,193 $ 17,971
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): December 31, 2020 September 30, 2020 Operating lease right-of-use assets, net $ 286,044 $ 300,680 Operating lease liabilities, current 1 46,763 46,010 Operating lease liabilities, long-term 328,468 338,715 Total operating lease liabilities $ 375,231 $ 384,725 Weighted average remaining lease term (in years) 10.1 10.2 Weighted average discount rate 2.59 % 2.58 % (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 December 31, 2020, the future operating lease payments for each of the next five years and thereafter is as follows (in thousands): Fiscal Years Ending September 30: Operating Lease 2021 (remainder) $ 41,075 2022 57,598 2023 44,656 2024 39,995 2025 33,588 2026 26,705 Thereafter 191,236 Total lease payments 434,853 Less: imputed interest (59,622) Total lease liabilities $ 375,231

Net Income Per Share (Tables)

Net Income Per Share (Tables)	3 Months Ended
	Dec. 31, 2020
Net Income Per Share [Abstract]
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): Three months ended 2020 2019 Numerator Net income $ 87,678 $ 98,527 Denominator Weighted average shares outstanding — basic 61,440 60,649 Dilutive effect of common shares from stock options and restricted stock units 842 166 Weighted average shares outstanding — diluted 62,282 60,815 Basic net income per share $ 1.43 $ 1.62 Diluted net income per share $ 1.41 $ 1.62

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Schedule of Revenues by Geographic Region	The following presents revenues by geographic region (in thousands): Three months ended 2020 2019 Americas: United States $ 320,343 $ 275,499 Other 22,793 26,063 Total Americas 343,136 301,562 EMEA 162,084 155,952 Asia Pacific 119,397 111,791 $ 624,617 $ 569,305
Schedule of Product Revenues by Systems and Software	The following presents net product revenues by systems and software (in thousands): Three months ended 2020 2019 Net product revenues Systems revenue $ 178,571 $ 169,601 Software revenue 109,474 64,935 Total net product revenue $ 288,045 $ 234,536
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: Three months ended 2020 2019 Ingram Micro, Inc. 18.1 % 16.5 % Westcon Group, Inc. — 11.0 % Arrow ECS — 10.1 % Synnex Corporation 10.0 % —
Long-lived Assets by Geographic Areas	The Company tracks assets by physical location. Long-lived assets consist of property and equipment, net, and are shown below (in thousands): December 31, September 30, United States $ 178,638 $ 190,509 EMEA 19,405 20,361 Other countries 17,606 18,369 $ 215,649 $ 229,239

Restructuring Charges (Tables)

Restructuring Charges (Tables)	3 Months Ended
	Dec. 31, 2019
Restructuring Charges [Abstract]
Restructuring and Related Costs	During the three months ended December 31, 2019, the following activity was recorded (in thousands): Employee Severance, Benefits and Related Costs Accrued expenses, October 1, 2019 $ — Restructuring charges 7,800 Cash payments (5,282) Non-cash items — Accrued expenses, December 31, 2019 $ 2,518

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Capitalized contract acquisition costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Changes In Capitalized Contract Cost [Roll Forward]
Beginning Balance	$ 70,396	$ 59,446
Additional capitalized contract acquisition costs deferred	9,725	7,412
Amortization of capitalized contract acquisition costs	(8,152)	(8,705)
Ending Balance	$ 71,969	$ 58,153

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Narrative (Details) - USD ($)	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Amortization of capitalized contract acquisition costs	$ 8,152,000	$ 8,705,000
Capitalized Contract Cost, Impairment Loss	$ 0	$ 0

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Change in Contract with Customer, Asset [Roll Forward]
Beginning Balance	$ 200,472	$ 132,492
Revenue recognized during period but not yet billed	18,316	3,407
Contract asset additions	55,834	12,930
Contract assets reclassified to accounts receivable	(28,818)	(13,584)
Ending Balance	245,804	135,245
Change in Contract with Customer, Liability [Roll Forward]
Beginning Balance	1,272,632	1,198,116
Amounts billed but not recognized as revenues	421,918	346,132
Revenues recognized related to the opening balance of deferred revenue	(335,725)	(306,275)
Ending Balance	$ 1,358,825	$ 1,237,973

Revenue from Contracts with C_6

Revenue from Contracts with Customers - Remaining Performance Obligations (Details) $ in Billions	Dec. 31, 2020USD ($)
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation, amount	$ 1.4
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation, percentage	68.90%
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]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation, percentage	18.90%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Cash equivalents, fair value	$ 494,901	$ 250,970
Investments, fair value	930,169	714,242
Corporate Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	179,694	189,662
Debt Securities, Available-for-sale, Noncurrent	72,173	102,939
Municipal Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	2,916	6,146
U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	116,526	117,374
U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	47,379	47,151
Debt Securities, Available-for-sale, Noncurrent	16,580
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Cash equivalents, fair value	286,495	43,553
Investments, fair value	286,495	43,553
Level 1 | Corporate Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	0
Debt Securities, Available-for-sale, Noncurrent	0	0
Level 1 | Municipal Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	0
Level 1 | U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	0
Level 1 | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	0
Debt Securities, Available-for-sale, Noncurrent	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Cash equivalents, fair value	208,406	207,417
Investments, fair value	643,674	670,689
Level 2 | Corporate Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	179,694	189,662
Debt Securities, Available-for-sale, Noncurrent	72,173	102,939
Level 2 | Municipal Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	2,916	6,146
Level 2 | U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	116,526	117,374
Level 2 | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	47,379	47,151
Debt Securities, Available-for-sale, Noncurrent	16,580
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Cash equivalents, fair value	0	0
Investments, fair value	0	0
Level 3 | Corporate Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	0
Debt Securities, Available-for-sale, Noncurrent	0	0
Level 3 | Municipal Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	0
Level 3 | U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	0
Level 3 | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Current	0	$ 0
Debt Securities, Available-for-sale, Noncurrent	$ 0

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Operating Lease, Impairment Loss	$ 6.7
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Operating Lease, Impairment Loss		$ 0

Short-Term and Long-Term Inve_3

Short-Term and Long-Term Investments - Schedule of Short-Term and Long-Term Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Schedule of Investments [Line Items]
Interest income from investments	$ 1,100	$ 5,600
Short-Term Investments
Schedule of Investments [Line Items]
Cost or amortized cost	345,967		$ 359,586
Gross unrealized gains	558		756
Gross unrealized losses	(10)		(9)
Fair value	346,515		360,333
Short-Term Investments | Corporate Bonds and Notes
Schedule of Investments [Line Items]
Cost or amortized cost	179,159		188,932
Gross unrealized gains	540		736
Gross unrealized losses	(5)		(6)
Fair value	179,694		189,662
Short-Term Investments | Municipal Bonds and Notes
Schedule of Investments [Line Items]
Cost or amortized cost	2,916		6,143
Gross unrealized gains	0		3
Gross unrealized losses	0		0
Fair value	2,916		6,146
Short-Term Investments | U.S. Government Securities
Schedule of Investments [Line Items]
Cost or amortized cost	116,515		117,363
Gross unrealized gains	15		14
Gross unrealized losses	(4)		(3)
Fair value	116,526		117,374
Short-Term Investments | U.S. Government Agency Securities
Schedule of Investments [Line Items]
Cost or amortized cost	47,377		47,148
Gross unrealized gains	3		3
Gross unrealized losses	(1)		0
Fair value	47,379		47,151
Long-Term Investments
Schedule of Investments [Line Items]
Cost or amortized cost	88,291		102,206
Gross unrealized gains	462		756
Gross unrealized losses	0		(23)
Fair value	88,753		102,939
Long-Term Investments | Corporate Bonds and Notes
Schedule of Investments [Line Items]
Cost or amortized cost	71,711		102,206
Gross unrealized gains	462		756
Gross unrealized losses	0		(23)
Fair value	72,173		$ 102,939
Long-Term Investments | U.S. Government Agency Securities
Schedule of Investments [Line Items]
Cost or amortized cost	16,580
Gross unrealized gains	0
Gross unrealized losses	0
Fair value	$ 16,580

Short-Term and Long-Term Inve_4

Short-Term and Long-Term Investments - Schedule of Investments That Have Been in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Fair Value
Less than 12 months	$ 88,883	$ 85,304
12 months or greater	0	5,006
Total	88,883	90,310
Gross Unrealized Losses
Less than 12 months	(10)	(31)
12 months or greater	0	(1)
Total	(10)	(32)
Corporate Bonds and Notes
Fair Value
Less than 12 months	26,703	43,492
12 months or greater	0	5,006
Total	26,703	48,498
Gross Unrealized Losses
Less than 12 months	(5)	(28)
12 months or greater	0	(1)
Total	(5)	(29)
U.S. Government Securities
Fair Value
Less than 12 months	29,053	41,812
12 months or greater	0	0
Total	29,053	41,812
Gross Unrealized Losses
Less than 12 months	(4)	(3)
12 months or greater	0	0
Total	(4)	$ (3)
U.S. Government Agency Securities
Fair Value
Less than 12 months	33,127
12 months or greater	0
Total	33,127
Gross Unrealized Losses
Less than 12 months	(1)
12 months or greater	0
Total	$ (1)

Business Combinations - Narrati

Business Combinations - Narrative (Details) - Shape Security, Inc. - USD ($) $ in Millions	Jan. 24, 2020	Dec. 31, 2020	Sep. 30, 2020
Business Acquisition [Line Items]
Total purchase price	$ 1,000
Transaction costs	$ 23.2
Identifiable intangible assets useful life	6 years 6 months
Goodwill, Other Increase (Decrease)		$ 4.9
General and Administrative Expense
Business Acquisition [Line Items]
Business combination, acquisition related costs			$ 15.3
Developed Technology Rights
Business Acquisition [Line Items]
Identifiable intangible assets useful life	7 years
Customer Relationships
Business Acquisition [Line Items]
Identifiable intangible assets useful life	4 years
Trade Names
Business Acquisition [Line Items]
Identifiable intangible assets useful life	5 years

Business Combinations - Purchas

Business Combinations - Purchase Price Allocation (Details) - USD ($) $ in Thousands	Jan. 24, 2020	Dec. 31, 2020	Sep. 30, 2020
Fair Value of intangible Assets [Abstract]
Goodwill		$ 1,863,892	$ 1,858,966
Shape Security, Inc.
Assets Acquired [Abstract]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	$ 53,934
Fair Value of intangible Assets [Abstract]
Accounts receivable	21,077
Deferred tax assets	24,619
Operating lease right-of-use assets	29,644
Other tangible assets	$ 22,571
Identifiable intangible assets useful life	6 years 6 months
Goodwill	$ 804,537
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Total	1,106,882
Liabilities Assumed Abstract [Abstract]
Deferred revenue	(39,000)
Operating lease liabilities	(30,773)
Other assumed liabilities	(18,571)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(88,344)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net, Total	1,018,538
Shape Security, Inc. | Developed Technology Rights
Fair Value of intangible Assets [Abstract]
Identifiable intangible assets:	$ 120,000
Identifiable intangible assets useful life	7 years
Shape Security, Inc. | Customer Relationships
Fair Value of intangible Assets [Abstract]
Identifiable intangible assets:	$ 21,000
Identifiable intangible assets useful life	4 years
Shape Security, Inc. | Trade Names
Fair Value of intangible Assets [Abstract]
Identifiable intangible assets:	$ 9,500
Identifiable intangible assets useful life	5 years

Balance Sheet Details - Cash an

Balance Sheet Details - Cash and Cash Equivalent (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Balance Sheet Details [Abstract]
Cash and cash equivalents	$ 1,026,829	$ 849,556
Restricted cash included in other assets, net	3,373	3,270
Total cash, cash equivalents and restricted cash	$ 1,030,202	$ 852,826	$ 738,645	$ 602,254

Balance Sheet Details - Invento

Balance Sheet Details - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Balance Sheet Details [Abstract]
Finished goods	$ 15,839	$ 17,096
Raw materials	10,616	10,802
Inventories	$ 26,455	$ 27,898

Balance Sheet Details - Other C

Balance Sheet Details - Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Balance Sheet Details [Abstract]
Contract assets	$ 163,546	$ 138,096
Prepaid expenses	59,232	47,197
Capitalized contract acquisition costs	30,687	29,650
Other	29,876	44,563
Other Assets, Current	$ 283,341	$ 259,506

Balance Sheet Details - Other A

Balance Sheet Details - Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Balance Sheet Details [Abstract]
Intangible assets	$ 223,371	$ 225,900
Contract assets	82,258	62,377
Capitalized contract acquisition costs	41,282	40,746
Other	21,044	18,424
Other Assets, Noncurrent	$ 367,955	$ 347,447

Balance Sheet Details - Accrued

Balance Sheet Details - Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Balance Sheet Details [Abstract]
Payroll and benefits	$ 141,378	$ 169,708
Operating lease liabilities, current	46,763	46,010
Income and other tax accruals	39,760	33,048
Other	77,891	72,632
Accrued Liabilities, Current	$ 305,792	$ 321,398

Balance Sheet Details - Other L

Balance Sheet Details - Other Long-term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Balance Sheet Details [Abstract]
Income taxes payable	$ 52,523	$ 49,846
Other	9,130	9,665
Other long-term liabilities	$ 61,653	$ 59,511

Debt Facilities - Narrative (De

Debt Facilities - Narrative (Details)	Jan. 31, 2020USD ($)	Jan. 24, 2020USD ($)	Dec. 31, 2020USD ($)extension
Term Loan Facility
Debt Instrument [Line Items]
Aggregate principal amount		$ 400,000,000
Debt issuance costs		$ 2,200,000	$ 1,500,000
Redemption percentage		1.25%
Long-term line of credit			$ 385,000,000
Interest rate at end of period			2.106%
Term Loan Facility | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate			1.125%
Term Loan Facility | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		1.125%
Term Loan Facility | London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%
Term Loan Facility | Alternate Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			0.125%
Term Loan Facility | Alternate Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		0.125%
Term Loan Facility | Alternate Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		0.75%
Revolving Credit Facility
Debt Instrument [Line Items]
Aggregate principal amount	$ 350,000,000
Long-term line of credit			$ 0
Conditional increase in borrowing capacity	$ 150,000,000
Number of extensions | extension			2
Length of extension period			1 year
Outstanding line of credit balance			$ 350,000,000
Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Commitment fee percentage	0.125%
Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Commitment fee percentage	0.30%
Revolving Credit Facility | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.125%
Revolving Credit Facility | London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Revolving Credit Facility | Alternate Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.125%
Revolving Credit Facility | Alternate Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	0.75%

Debt Facilities - Long-term Deb

Debt Facilities - Long-term Debt Maturities (Details) - Term Loan Facility $ in Thousands	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
2021 (remainder)	$ 15,000
2022	20,000
2023	350,000
Total	$ 385,000

Leases - Narrative (Details)

Leases - Narrative (Details) ft² in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2020USD ($)ft²	Sep. 30, 2020USD ($)	Oct. 01, 2019USD ($)
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 286,044	$ 300,680
Sublease Income	9,100
Sublease income payment remainder of fiscal year	3,300
Payment to be received in year two and three	5,800
Operating Lease, Impairment Loss	$ 6,700
Office Building
Lessee, Lease, Description [Line Items]
Operating lease, number of square feet | ft²	515
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets			$ 304,800
Lease liabilities			$ 386,400

Leases - Operating Lease Expens

Leases - Operating Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease expense	$ 12,181	$ 11,318
Short-term lease expense	986	814
Variable lease expense	7,026	5,839
Total lease expense	$ 20,193	$ 17,971

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Leases [Abstract]
Operating lease right-of-use assets	$ 286,044	$ 300,680
Operating lease liabilities, current	46,763	46,010
Operating lease liabilities, long-term	328,468	338,715
Total lease liabilities	$ 375,231	$ 384,725
Weighted average remaining lease term (in years)	10 years 1 month 6 days	10 years 2 months 12 days
Weighted average discount rate	2.59%	2.58%

Leases - Maturities of Lease Li

Leases - Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Leases [Abstract]
2021 (remainder)	$ 41,075
2022	57,598
2023	44,656
2024	39,995
2025	33,588
2026	26,705
Thereafter	191,236
Total lease payments	434,853
Less: imputed interest	(59,622)
Total lease liabilities	$ 375,231	$ 384,725

Commitments And Contingencies (

Commitments And Contingencies (Details)	3 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Product warranty period	1 year

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Effective tax rate	25.10%	22.80%
Unrecognized tax benefit	$ 54.3

Net Income Per Share (Details)

Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Numerator
Net income	$ 87,678	$ 98,527
Denominator
Weighted average shares outstanding — basic (shares)	61,440	60,649
Dilutive effect of common shares from stock options and restricted stock units	842	166
Weighted average shares outstanding — diluted (shares)	62,282	60,815
Basic net income per share (dollars per share)	$ 1.43	$ 1.62
Diluted net income per share (dollars per share)	$ 1.41	$ 1.62

Segment Information (Details)

Segment Information (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2020USD ($)segmentgeographic_region	Dec. 31, 2019USD ($)	Sep. 30, 2020USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	1
Number of geographic regions | geographic_region	3
Net revenues	$ 624,617	$ 569,305
Long-lived assets	215,649		$ 229,239
Product
Segment Reporting Information [Line Items]
Net revenues	288,045	234,536
Software [Member] | Product
Segment Reporting Information [Line Items]
Net revenues	109,474	64,935
Systems [Member] | Product
Segment Reporting Information [Line Items]
Net revenues	178,571	169,601
United States
Segment Reporting Information [Line Items]
Net revenues	320,343	275,499
Long-lived assets	178,638		190,509
Other
Segment Reporting Information [Line Items]
Net revenues	22,793	26,063
Total Americas
Segment Reporting Information [Line Items]
Net revenues	343,136	301,562
EMEA
Segment Reporting Information [Line Items]
Net revenues	162,084	155,952
Long-lived assets	19,405		20,361
Asia Pacific
Segment Reporting Information [Line Items]
Net revenues	119,397	$ 111,791
Other countries
Segment Reporting Information [Line Items]
Long-lived assets	$ 17,606		$ 18,369
Ingram Micro, Inc. | Net Revenue | Geographic Concentration
Segment Reporting Information [Line Items]
Concentration risk percentage	18.10%	16.50%
Westcon Group, Inc. | Net Revenue | Geographic Concentration
Segment Reporting Information [Line Items]
Concentration risk percentage	0.00%	11.00%
Arrow ECS | Net Revenue | Geographic Concentration
Segment Reporting Information [Line Items]
Concentration risk percentage	0.00%	10.10%
Synnex Corporation | Net Revenue | Geographic Concentration
Segment Reporting Information [Line Items]
Concentration risk percentage	10.00%	0.00%

Restructuring Charges - Narrati

Restructuring Charges - Narrative (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)employee
Restructuring Charges [Abstract]
Number of employees in reduction of force program | employee		75
Restructuring charges | $	$ 0	$ 7,800

Restructuring Charges - Restruc

Restructuring Charges - Restructuring Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Restructuring Reserve [Roll Forward]
Accrued expenses (Beginning balance)		$ 0
Restructuring charges	$ 0	7,800
Cash payments		(5,282)
Non-cash items		0
Accrued expenses (Ending balance)		$ 2,518

Subsequent Event (Details)

Subsequent Event (Details) - USD ($) $ in Millions	Feb. 03, 2021	Jan. 22, 2021	Dec. 31, 2020
Subsequent Event [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 1,300
Volterra [Member]
Subsequent Event [Line Items]
Transaction costs			$ 2.7
Subsequent Event
Subsequent Event [Line Items]
Accelerated Share Repurchases, Settlement (Payment) or Receipt	$ 500
Accelerated Share Repurchases, Cash or Stock Settlement	approximates 80 percent of the total number of shares to be repurchased under the ASR agreements.
Subsequent Event | Volterra [Member]
Subsequent Event [Line Items]
Payments to Acquire Businesses, Gross		$ 440
Business Combination, Consideration Transferred, Other		$ 60