Mimecast (MIME) 10-K 22 May 20 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Mar. 31, 2020	May 08, 2020	Sep. 30, 2019
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Trading Symbol	MIME
Title of 12(b) Security	Ordinary Shares, nominal value $0.012 per share
Security Exchange Name	NASDAQ
Entity Registrant Name	MIMECAST LIMITED
Entity Central Index Key	0001644675
Current Fiscal Year End Date	--03-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 1,990,718,872
Entity Common Stock, Shares Outstanding		62,965,224
Entity File Number	001-37637
Entity Incorporation, State or Country Code	Y9
Entity Tax Identification Number	00-0000000
Entity Address, Address Line One	1 Finsbury Avenue
Entity Address, City or Town	London
Entity Address, Country	GB
Entity Address, Postal Zip Code	EC2M 2PF
City Area Code	781
Local Phone Number	996-5340
Document Annual Report	true
Document Transition Report	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Current assets
Cash and cash equivalents	$ 173,958	$ 137,576
Short-term investments		35,941
Accounts receivable, net	97,659	80,953
Deferred contract costs, net	11,133	8,140
Prepaid expenses and other current assets	16,145	25,871
Total current assets	298,895	288,481
Property and equipment, net	85,178	94,202
Operating lease right-of-use assets	116,564
Intangible assets, net	38,394	30,623
Goodwill	150,525	107,575
Deferred contract costs, net of current portion	36,664	28,250
Other assets	3,614	5,156
Total assets	729,834	554,287
Current liabilities
Accounts payable	14,907	9,457
Accrued expenses and other current liabilities	41,607	44,309
Deferred revenue	194,151	163,102
Current portion of finance lease obligations	1,058	844
Current portion of operating lease liabilities	30,379
Current portion of long-term debt	6,573	4,059
Total current liabilities	288,675	221,771
Deferred revenue, net of current portion	12,816	12,472
Long-term finance lease obligations	323	1,381
Operating lease liabilities	105,321
Long-term debt	86,258	92,797
Construction financing lease obligations		36,650
Other non-current liabilities	4,386	15,581
Total liabilities	497,779	380,652
Commitments and contingencies (Note 14)
Shareholders' equity
Ordinary shares, $0.012 par value, 300,000,000 shares authorized; 62,791,691 and 61,158,051 shares issued and outstanding as of March 31, 2020 and 2019, respectively	754	734
Additional paid-in capital	325,808	263,388
Accumulated deficit	(83,660)	(83,632)
Accumulated other comprehensive loss	(10,847)	(6,855)
Total shareholders' equity	232,055	173,635
Total liabilities and shareholders' equity	$ 729,834	$ 554,287

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2020	Mar. 31, 2019
Statement Of Financial Position [Abstract]
Ordinary shares, par value	$ 0.012	$ 0.012
Ordinary shares, authorized	300,000,000	300,000,000
Ordinary shares, issued	62,791,691	61,158,051
Ordinary shares, outstanding	62,791,691	61,158,051

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Revenue	$ 426,963,000	$ 340,377,000	$ 261,897,000
Cost of revenue	109,382,000	90,874,000	69,699,000
Gross profit	317,581,000	249,503,000	192,198,000
Operating expenses
Research and development	80,790,000	57,939,000	38,373,000
Sales and marketing	169,179,000	139,194,000	121,246,000
General and administrative	65,314,000	53,759,000	36,989,000
Impairment of long-lived assets	0	0	1,712,000
Restructuring		(170,000)	832,000
Total operating expenses	315,283,000	250,722,000	199,152,000
Income (loss) from operations	2,298,000	(1,219,000)	(6,954,000)
Other income (expense)
Interest income	3,446,000	2,515,000	1,310,000
Interest expense	(4,507,000)	(5,940,000)	(598,000)
Foreign exchange expense and other, net	(1,078,000)	(356,000)	(3,439,000)
Total other income (expense), net	(2,139,000)	(3,781,000)	(2,727,000)
Income (loss) before income taxes	159,000	(5,000,000)	(9,681,000)
Provision for income taxes	2,359,000	2,001,000	2,705,000
Net loss	$ (2,200,000)	$ (7,001,000)	$ (12,386,000)
Net loss per ordinary share
Basic and diluted	$ (0.04)	$ (0.12)	$ (0.22)
Weighted-average number of ordinary shares outstanding
Basic and diluted	62,024	59,960	57,269

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (2,200)	$ (7,001)	$ (12,386)
Other comprehensive (loss) income:
Net unrealized (losses) gains on investments, net of tax	(28)	117	40
Change in foreign currency translation adjustment	(3,964)	(1,625)	2,839
Reclassification of cumulative translation adjustment to net loss upon liquidation of subsidiaries, net of tax			188
Total other comprehensive (loss) income	(3,992)	(1,508)	3,067
Comprehensive loss	$ (6,192)	$ (8,509)	$ (9,319)

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands		Total	Ordinary Shares [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Cumulative effect adjustment | ASU 2016-09 [Member]	[1]			$ 104	$ (104)
Beginning balance at Mar. 31, 2017		$ 81,992	$ 671	183,752	(94,017)	$ (8,414)
Beginning balance, Shares at Mar. 31, 2017			55,902,000
Excess tax benefits related to exercise of share options		217		217
Net loss		(12,386)			(12,386)
Foreign currency translation adjustment		3,027				3,027
Unrealized gain (losses) on investments		40				40
Issuance of ordinary shares upon exercise of share options		15,636	$ 36	15,600
Issuance of ordinary shares upon exercise of share options, Shares			2,961,000
Share-based compensation		11,763		11,763
Employee share purchase plan (ESPP) purchase		1,492		1,492
Employee share purchase plan (ESPP) purchase, Shares			67,000
Tax withholdings on issuance of ordinary shares		(89)		(89)
Tax withholdings on issuance of ordinary shares, Shares			(3,000)
Vesting of restricted share units (RSUs), Shares			23,000
Ending balance at Mar. 31, 2018		101,692	$ 707	212,839	(106,507)	(5,347)
Ending balance, Shares at Mar. 31, 2018			58,950,000
Cumulative effect adjustment | ASU 2014-09 [Member]	[2]	29,876			29,876
Net loss		(7,001)			(7,001)
Foreign currency translation adjustment		(1,625)				(1,625)
Unrealized gain (losses) on investments		117				117
Issuance of ordinary shares upon exercise of share options		21,353	$ 25	21,328
Issuance of ordinary shares upon exercise of share options, Shares			2,055,000
Share-based compensation		25,929		25,929
Employee share purchase plan (ESPP) purchase		3,633	$ 2	3,631
Employee share purchase plan (ESPP) purchase, Shares			138,000
Vesting of restricted share units (RSUs), Shares			24,000
Tax withholding on ESPP purchases and vesting of RSUs		(339)		(339)
Tax withholding on ESPP purchases and vesting of RSUs, Shares			(9,000)
Ending balance at Mar. 31, 2019		$ 173,635	$ 734	263,388	(83,632)	(6,855)
Ending balance, Shares at Mar. 31, 2019		61,158,051	61,158,000
Cumulative effect adjustment | ASU 2016-02 [Member]	[3]	$ 2,172			2,172
Net loss		(2,200)			(2,200)
Foreign currency translation adjustment		(3,964)				(3,964)
Unrealized gain (losses) on investments		(28)				(28)
Issuance of ordinary shares upon exercise of share options		$ 20,144	$ 16	20,128
Issuance of ordinary shares upon exercise of share options, Shares		1,359,903	1,360,000
Share-based compensation		$ 39,488		39,488
Employee share purchase plan (ESPP) purchase		5,284	$ 2	5,282
Employee share purchase plan (ESPP) purchase, Shares			165,000
Vesting of restricted share units (RSUs)			$ 2	(2)
Vesting of restricted share units (RSUs), Shares			161,000
Tax withholding on ESPP purchases and vesting of RSUs		(2,476)		(2,476)
Tax withholding on ESPP purchases and vesting of RSUs, Shares			(52,000)
Ending balance at Mar. 31, 2020		$ 232,055	$ 754	$ 325,808	$ (83,660)	$ (10,847)
Ending balance, Shares at Mar. 31, 2020		62,791,691	62,792,000
[1]	Accounting Standards Update (ASU) No. 2016-09, Compensation – Stock Compensation
[2]	ASU No. 2014-09, Revenue from Contracts with Customers: Topic 606
[3]	ASU No. 2016-02, Leases (Topic 842) (ASU 2016-02 or ASC 842)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Operating activities
Net loss	$ (2,200,000)	$ (7,001,000)	$ (12,386,000)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	32,245,000	29,953,000	18,960,000
Share-based compensation expense	39,544,000	25,954,000	11,734,000
Amortization of deferred contract costs	9,587,000	6,390,000
Amortization of debt issuance costs	501,000	336,000
Amortization of operating lease right-of-use assets	31,940,000
Impairment of long-lived assets	0	0	1,712,000
Other non-cash items	(54,000)	(400,000)	365,000
Unrealized currency losses on foreign denominated transactions	1,567,000	880,000	2,958,000
Changes in assets and liabilities:
Accounts receivable	(20,467,000)	(18,771,000)	(17,935,000)
Prepaid expenses and other current assets	8,808,000	(2,046,000)	(5,037,000)
Deferred contract costs	(22,751,000)	(20,219,000)
Other assets	(1,161,000)	(2,045,000)	33,000
Accounts payable	4,215,000	2,093,000	(104,000)
Deferred revenue	38,457,000	45,901,000	39,042,000
Operating lease liabilities	(25,941,000)
Accrued expenses and other liabilities	(3,752,000)	5,210,000	7,070,000
Net cash provided by operating activities	90,538,000	66,235,000	46,412,000
Investing activities
Purchases of strategic investments	(3,025,000)
Purchases of investments		(42,856,000)	(76,948,000)
Maturities of investments	36,000,000	66,000,000	77,808,000
Purchases of property, equipment and capitalized software	(53,234,000)	(28,795,000)	(34,498,000)
Payments for acquisitions, net of cash acquired	(45,280,000)	(115,673,000)	(1,381,000)
Net cash used in investing activities	(65,539,000)	(121,324,000)	(35,019,000)
Financing activities
Proceeds from issuance of ordinary shares	25,428,000	24,986,000	17,128,000
Withholding taxes related to net share settlement of ESPP purchases and vesting of RSUs	(2,476,000)	(298,000)	(89,000)
Payments on debt	(4,375,000)	(1,875,000)	(1,825,000)
Payments on finance lease obligations	(844,000)	(1,275,000)	(1,039,000)
Payments on construction financing lease obligations		(2,301,000)	(1,019,000)
Proceeds from issuance of debt, net of issuance costs		97,748,000
Net cash provided by financing activities	17,733,000	116,985,000	13,156,000
Effect of foreign exchange rates on cash	(6,350,000)	(2,659,000)	2,471,000
Net increase in cash and cash equivalents	36,382,000	59,237,000	27,020,000
Cash and cash equivalents at beginning of period	137,576,000	78,339,000	51,319,000
Cash and cash equivalents at end of period	173,958,000	137,576,000	78,339,000
Supplemental disclosure of cash flow information
Cash paid during the period for interest	4,114,000	4,598,000	591,000
Cash paid during the period for income taxes	2,489,000	3,010,000	2,545,000
Supplemental disclosure of non-cash investing and financing activities
Unpaid purchases of property, equipment and capitalized software	13,232,000	7,634,000	7,977,000
Property and equipment acquired under capital lease			4,000,000
Construction costs capitalized under financing lease obligations		27,903,000	$ 70,645,000
Derecognition of building upon completion of construction period		(56,794,000)
Operating lease right-of-use assets exchanged for lease obligations	$ 13,982,000
Withholding taxes payable upon RSU vesting		$ 41,000

Organization and Description of

Organization and Description of Business	12 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Organization and Description of Business	1. Organization and Description of Business Mimecast Limited (Mimecast Jersey) is a public limited company organized under the laws of the Bailiwick of Jersey on July 28, 2015. On November 4, 2015, Mimecast Jersey changed its corporate structure whereby it became the holding company of Mimecast Limited (Mimecast UK), a private limited company incorporated in 2003 under the laws of England and Wales, and its wholly-owned subsidiaries by way of a share-for-share exchange in which the shareholders of Mimecast UK exchanged their shares in Mimecast UK for an identical number of shares of the same class in Mimecast Jersey. Upon the exchange, the historical consolidated financial statements of Mimecast UK became the historical consolidated financial statements of Mimecast Jersey. Mimecast Jersey and its subsidiaries (together, the Group, the Company, or Mimecast) is headquartered in London, England. The principal activity of the Group is the provision of email management services. Delivered as a software-as-a-service (SaaS), Mimecast’s Email Security 3.0 offerings and Cyber Resilience Extensions include email security, awareness training, continuity, archiving, and web security. By unifying disparate and fragmented email environments into one holistic solution from the cloud, Mimecast minimizes risk and reduces cost and complexity while providing total end-to-end control of email. Mimecast’s proprietary software platform provides a single system to address key email management issues. Mimecast operates principally in Europe, North America, Africa and Australia. The Company is subject to a number of risks and uncertainties common to companies in similar industries and stages of development including, but not limited to, rapid technological changes, competition from substitute products and services from larger companies, customer concentration, management of international activities, protection of proprietary rights, patent litigation, and dependence on key individuals.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The accompanying consolidated financial statements reflect the application of certain significant accounting policies as described below and elsewhere in these notes to the consolidated financial statements. The Company believes that a significant accounting policy is one that is both important to the portrayal of the Company’s financial condition and results, and requires management’s most difficult, subjective, or complex judgments, often as the result of the need to make estimates about the effect of matters that are inherently uncertain. Basis of Presentation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB). The Company reclassified certain amounts within its consolidated statements of cash flows to conform to current period presentation. The reclassifications include $0.3 million and $0.1 million from proceeds from issuance of ordinary shares to withholding taxes related to net share settlement of ESPP purchases and vesting of RSUs for the years ended March 31, 2019 and 2018, respectively. These reclassifications had no impact on the Company’s previously reported results of operations or its balance sheets. Principles of Consolidation The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of income and expenses during the reporting period. Significant estimates relied upon in preparing these consolidated financial statements include revenue recognition, variable consideration, valuation at fair value of assets acquired or sold, including intangibles, goodwill, tangible assets, and liabilities assumed, amortization perio ds, expected future cash flows used to evaluate the recoverability of long-lived assets, contingent liabilities, determination of incremental borrowing rates, restructuring liabilities, expensing and capitalization of research and development costs for int ernal-use software, the determination of the fair value of share-based awards issued, the average period of benefit associated with costs capitalized to obtain revenue contracts and the recoverability of the Company’s net deferred tax assets and related va luation allowance. Although the Company regularly assesses these estimates, actual results could differ materially from these estimates. The Company bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances. Actual results may differ from management’s estimates if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. Changes in estimates are recorded in the period in which they become known. Subsequent Events Considerations The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated as required. See Note 18. Cash, Cash Equivalents and Investments The Company considers all highly liquid instruments purchased with an original maturity date of 90 days or less from the date of purchase to be cash equivalents. Cash and cash equivalents consist of cash on deposit with banks, amounts held in interest-bearing money market funds and investments with maturities of 90 days or less from the date of purchase. Cash equivalents are carried at cost, which approximates their fair market value. Investments not classified as cash equivalents are presented as either short-term or long-term investments based on both their stated maturities as well as the time period the Company intends to hold such securities. The Company determines the appropriate classification of investments at the time of purchase and reevaluates such designation at each balance sheet date. The Company adjusts the cost of investments for amortization of premiums and accretion of discounts to maturity. The Company includes such amortization and accretion in interest income in the consolidated statements of operations. The Company did not hold any debt investments as of March 31, 2020. When the Company holds debt investments classified as available-for-sale pursuant to ASC 320, Investments – Debt Securities, The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than its amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the investment, or if it is more likely than not that the Company will be required to sell the investment before recovery of the amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, compliance with the Company’s investment policy, the severity and the duration of the impairment and changes in value subsequent to the end of the period. As of March 31, 2020, the Company did not hold any investments. As of March 31, 2019, the aggregate fair value of investments held by the Company in an unrealized loss position for less than twelve months was $10.0 million. For the years ended March 31, 2020, 2019 and 2018, the Company determined that no other-than-temporary impairments were required to be recognized in the consolidated statements of operations. The following is a summary of cash, cash equivalents and investments as of March 31, 2020 and March 31, 2019: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value March 31, 2020: Cash and cash equivalents due in 90 days or less $ 173,958 $ — $ — $ 173,958 Total cash, cash equivalents and investments $ 173,958 $ — $ — $ 173,958 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value March 31, 2019: Cash and cash equivalents due in 90 days or less $ 137,576 $ — $ — $ 137,576 Investments: U.S. treasury securities due in one year or less 1,993 1 — 1,994 Non-U.S. government securities due in one year or less 7,969 12 — 7,981 Corporate securities due in one year or less 25,951 24 (9 ) 25,966 Total investments 35,913 37 (9 ) 35,941 Total cash, cash equivalents and investments $ 173,489 $ 37 $ (9 ) $ 173,517 Revenue Recognition Revenue Recognition Policy The Company recognizes revenue upon transfer of control of promised products or services to customers in an amount that reflects the consideration the Company expects to receive in exchange for those products or services. To achieve the core principle of ASC 606, the Company performs the following steps: 1) Identify the contract(s) with a customer; 2) Identify the performance obligations in the contract; 3) Determine the transaction price; 4) Allocate the transaction price to the performance obligations in the contract; and 5) Recognize revenue when (or as) the Company satisfies a performance obligation. The Company derives its revenue from two sources: (1) subscription revenue, which are comprised of subscription fees from customers accessing the Company’s cloud services and from customers purchasing additional support beyond the standard support that is included in the basic subscription fees; and (2) related professional services and other revenue, which consists primarily of certain performance obligations related to set-up, ingestion, consulting and training fees. In the years ended March 31, 2020, 2019 and 2018, subscription revenue made up the substantial majority of the Company’s revenue and professional services and other revenue made up less than 5% of the Company’s revenue. The Company’s subscription arrangements provide customers the right to access the Company’s hosted software applications. Customers do not have the right to take possession of the Company’s software during the hosting arrangement. The Company sells its products and services directly through the Company’s sales force and also indirectly through third-party resellers. In accordance with the provisions of ASC 606, the Company has considered certain factors in determining whether the end-user or the third-party reseller is the customer in arrangements involving resellers. The Company concluded that in the majority of transactions with resellers, the reseller is the customer. In these arrangements, the Company considered that it is the reseller, and not the Company, that has the relationship with the end-user. Specifically, the reseller has the ability to set pricing with the end-user and the credit risk with the end-user is borne by the reseller. Further, the reseller is not obligated to report its transaction price with the end-user to the Company, and in the majority of transactions, the Company is unable to determine the amount paid by the end-user customer to the reseller in these transactions. As a result of such considerations, revenue for these transactions is presented in the accompanying consolidated statements of operations based upon the amount billed to the reseller. For transactions where the Company has determined that the end-user is the ultimate customer, revenue is presented in the accompanying consolidated statements of operations based on the transaction price with the end-user. The Company recognizes subscription and support revenue ratably over the term of the contract, typically one year in duration, beginning on the date the customer is provided access to the Company’s service. For performance obligations related to set-up and ingestion, including implementation assistance and data migration services, respectively, the Company recognizes revenue using output measures of performance that reflect the transfer of promised services to the customer consistent with progress to completion. The Company considers training, consulting, and other professional services contracts as separate performance obligations and recognizes revenue using output measures of performance as services are completed. Amounts that have been invo iced are recorded in accounts receivable and in deferred revenue or revenue, depending on whether the revenue recognition criteria have been met. The Company primarily bills and collects payments from customers for its services in advance on a monthly and annual basis. In some instances, the Company receives non-refundable upfront payments for activities that do not constitute a promise to transfer a service and therefore are considered administrative tasks, not separate performance obligations. The upfront payments are evaluated to determine whether a material right to a discount upon renewal of the subscription exists. When the Company concludes a material right does not exist, the Company recognizes revenue related to the upfront payment over the initial contract term. When the Company concludes a material right does exist, the Company recognizes revenue related to the upfront payment, under the look-through method, over the estimated customer benefit period, which has been determined to be six years. All of the Company’s performance obligations, and associated revenue, are generally transferred to customers over time, with the exception of training, consulting and other professional services, which are generally transferred to the customer at a point in time. Revenue is presented net of any taxes collected from customers. Some of the Company’s contracts with customers contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative standalone selling price basis. The Company determines the standalone selling prices based on the Company’s overall pricing objectives, taking into consideration market conditions and other factors, including the value of the Company’s contracts, the products sold, customer demographics, the Company’s sales channel, and the number and size of users within the Company’s contracts. Deferred revenue primarily consists of billings or payments received in advance of revenue recognition from subscription and other services described above and is recognized as the revenue recognition criteria are met. Deferred revenue that is expected to be recognized during the succeeding twelve-month period is recorded as current deferred revenue and the remaining portion is recorded as non-current in the accompanying consolidated balance sheets. Deferred Cost Policy T he Company capitalizes incremental costs of obtaining revenue contracts, which primarily consist of commissions paid to its sales representatives. The Company amortizes these commissions over six years on a systematic basis, consistent with the pattern of transfer of the goods or services to which the asset relates. Six years represents the estimated benefit period of the customer relationship taking into account factors such as peer estimates of technology lives and customer lives as well as the Company's own historical data. No commissions are paid related to contract renewals. The current and noncurrent portions of deferred commissions are included in deferred contract costs, net, and deferred contract costs, net of current portion, respectively, in the accompanying consolidated balance sheets. Cost of Revenue Cost of revenue primarily consists of expenses related to supporting and hosting the Company’s product offerings and delivering professional services. These costs include salaries, benefits, incentive compensation and share-based compensation expense related to the management of the Company’s data centers, customer support team and the Company’s professional services team. In addition to these costs, the Company incurs third-party service provider costs such as data center and networking expenses, allocated overhead, amortization of capitalized software and acquired Concentration of Credit Risk and Off-Balance Sheet Risk The Company has no off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments, which potentially subject the Company to concentrations of credit risk, consist primarily of cash and cash equivalents, investments and accounts receivable. The Company maintains its cash, cash equivalents and investments with major financial institutions of high-credit quality. Although the Company deposits its cash with multiple financial institutions, its deposits, at times, may exceed federally insured limits. Credit risk with respect to accounts receivable is dispersed due to our large number of customers. The Company’s accounts receivable are derived from revenue earned from customers primarily located in the United States, the United Kingdom, and South Africa. The Company generally does not require its customers to provide collateral or other security to support accounts receivable. Credit losses historically have not been significant and the Company generally has not experienced any material losses related to receivables from individual customers, or groups of customers. Due to these factors, no additional credit risk beyond amounts provided for collection losses is believed by management to be probable in the Company’s accounts receivable. As of March 31, 2020 and 2019, no individual customer represented more than 10% of the Company’s accounts receivable. During the years ended March 31, 2020, 2019 and 2018, no individual customer represented more than 10% of the Company’s revenue. The Company's board of directors approved investment policy permits investments in fixed income securities denominated and payable in U.S. dollars, including U.S. government and agency securities, non-U.S. government securities, money market instruments, commercial paper, certificates of deposit, corporate bonds and asset-backed securities. The Company diversifies its investment portfolio by investing in multiple types of investment-grade securities across various industries and issuers, limiting the amount invested in individual securities and limiting the average maturity to two years or less and attempts to mitigate a risk of loss by using a third-party investment manager. As of March 31, 2020, the Company did not hold any investments. As of March 31, 2019, the Company’s investments consisted primarily of investment-grade fixed income corporate debt securities with maturities ranging from one to seven months, non-U.S. government securities with maturities ranging from three to eight months and U.S. treasury securities with maturities in approximately five months. Allowance for Doubtful Accounts The Company makes judgments as to its ability to collect outstanding receivables and provide allowances for the portion of receivables when a loss is reasonably expected to occur. The allowance for doubtful accounts is established to represent the best estimate of the net realizable value of the outstanding accounts receivable. The development of the allowance for doubtful accounts is based on a review of past due amounts, historical write-off and recovery experience, as well as aging trends affecting specific accounts and general operational factors affecting all amounts. In addition, factors are developed utilizing historical trends in bad debts, returns and allowances. The Company considers current economic trends when evaluating the adequacy of the allowance for doubtful accounts. If circumstances relating to specific customers change or unanticipated changes occur in the general business environment, the Company’s estimates of the recoverability of receivables could be further adjusted. For the years ended March 31, 2020, 2019 and 2018, bad debt expense was $0.3 million, $0.2 million and $0.2 million, respectively. The allowance for doubtful accounts as of March 31, 2020 and 2019 was not material. Property and Equipment Property and equipment are stated at cost and are depreciated using the straight-line method over the estimated useful life of the assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the related asset. Property and equipment acquired under capital leases is amortized over the lease term or, in circumstances where ownership is transferred by the end of the lease or there is a bargain purchase option, over the useful life that would be assigned if the asset were owned. Upon retirement or sale, the cost of assets disposed of, and the related accumulated depreciation, are removed from the accounts, and any resulting gain or loss is included in the determination of net loss in the period of retirement or sale. The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life Computer equipment 3 to 5 Leasehold improvements Lesser of asset life or lease term Furniture and fixtures 5 Office equipment 3 Expenditures for maintenance and repairs are charged to expense as incurred, whereas major betterments are capitalized as additions to property and equipment. Business Combinations In accordance with ASC 805, Business Combinations The Company recognizes identifiable assets acquired and liabilities assumed at their acquisition date fair value. Goodwill as of the acquisition date is measured as the excess of consideration transferred over the net of the acquisition date fair value of the assets acquired and the liabilities assumed and represents the expected future economic benefits arising from other assets acquired that are not individually identified and separately recognized. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to accurately value assets acquired and liabilities assumed at the acquisition date, its estimates are inherently uncertain and subject to refinement. Assumptions may be incomplete or inaccurate, and unanticipated events or circumstances may occur, which may affect the accuracy or validity of such assumptions, estimates or actual results. As a result, during the measurement period, which may be up to one year from the acquisition date, the Company records adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill to the extent that it identifies adjustments to the preliminary purchase price allocation. Upon the conclusion of the measurement period or final determination of the values of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the consolidated statements of operations. Goodwill and acquired intangible assets Goodwill is not amortized, but is evaluated for impairment annually, or whenever events or changes in circumstances indicate that the carrying value may not be recoverable. The Company has determined that there is a single reporting unit for the purpose of conducting this goodwill impairment assessment. For purposes of assessing potential impairment, the Company estimates the fair value of the reporting unit, based on the Company’s market capitalization, and compares this amount to the carrying value of the reporting unit. If the Company determines that the carrying value of the reporting unit exceeds its fair value, an impairment charge would be required. The annual goodwill impairment test is performed as of January 1 st Intangible assets acquired in a business combination are recorded at their estimated fair values at the date of acquisition. The Company amortizes acquired definite-lived intangible assets over their estimated useful lives based on the pattern of consumption of the economic benefits or, if that pattern cannot be readily determined, on a straight-line basis. Impairment of Long-Lived Assets The Company reviews long-lived assets, including property and equipment, right-of-use assets, and definite-lived intangible assets, for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. During this review, the Company re-evaluates the significant assumptions used in determining the original cost and estimated lives of long-lived assets. Although the assumptions may vary from asset to asset, they generally include operating results, changes in the use of the asset, cash flows, and other indicators of value. Management then determines whether the remaining useful life continues to be appropriate, or whether there has been an impairment of long-lived assets based primarily upon whether expected future undiscounted cash flows are sufficient to support the recoverability of these assets. Recoverability of these assets is measured by comparison of the carrying amount of the asset to the future undiscounted cash flows the asset is expected to generate. If the asset is considered to be impaired, the amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired asset. For the years ended March 31, 2020 and 2019, the Company did not identify any indicators of impairment of its long-lived assets. For the year ended March 31, 2018, the Company recorded an i Fair Value Measurements ASC 820, Fair Value Measurements and Disclosures ASC 820 identifies fair value as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants based on the highest and best use of the asset or liability. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. The Company uses valuation techniques to measure fair value that maximize the use of observable inputs and minimize the use of unobservable inputs. These inputs are prioritized as follows: • Level 1 inputs—Unadjusted observable quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. • Level 2 inputs—Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. • Level 3 inputs—Unobservable inputs for determining the fair values of assets or liabilities that reflect an entity’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The Company evaluates assets and liabilities subject to fair value measurements on a recurring and nonrecurring basis to determine the appropriate level to classify them for each reporting period. The Company measures eligible assets and liabilities at fair value, with changes in value recognized in earnings. Fair value treatment may be elected either upon initial recognition of an eligible asset or liability or, for an existing asset or liability, if an event triggers a new basis of accounting. The Company did not elect to remeasure any of its existing financial assets or liabilities and did not elect the fair value option for any financial assets and liabilities transacted in the years ended March 31, 2020, 2019 and 2018. Software Development Costs Costs incurred to develop software applications used in the Company’s SaaS platform consist of certain direct costs of materials and services incurred in developing or obtaining internal-use computer software, and payroll and payroll-related costs for employees who are directly associated with, and who devote time to, the project. These costs generally consist of internal labor during configuration, coding, and testing activities. Research and development costs incurred during the preliminary project stage or costs incurred for data conversion activities, training, maintenance and general and administrative or overhead costs are expensed as incurred. Once an application has reached the development stage, internal and external costs, if direct and incremental, are capitalized until the application is substantially complete and ready for its intended use. Qualified costs incurred during the operating stage of the Company’s software applications relating to upgrades and enhancements are capitalized to the extent it is probable that they will result in added functionality, while costs incurred for maintenance of, and minor upgrades and enhancements to, internal-use software are expensed as incurred. During the years ended March 31, 2020, 2019 and 2018, the Company believes the substantial majority of its development efforts were either in the preliminary project stage of development or in the operation stage (post-implementation), and accordingly, no costs have been capitalized during these periods. These costs are included in the accompanying consolidated statements of operations as research and development expense. Capitalized software and Cloud-computing Arrangements (CCA) The Company accounts for acquired internal-use software licenses and certain costs related to video content production related to its awareness training offering within the scope of ASC 350-40, Intangibles – Goodwill and Other – Internal-Use Software Additionally, the Company evaluates its accounting for fees paid in a CCA to determine whether the CCA includes a license to internal-use software. If the CCA includes a software license, the Company accounts for the software license as an intangible asset. Acquired software licenses are recognized and measured at cost, which includes the present value of the license obligation if the license is to be paid for over time. If the CCA does not include a software license, the Company accounts for the arrangement as a service contract (hosting arrangement) and hosting costs are generally expensed as incurred. Since the adoption of ASU 2018-15, Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-24): Customer’s Acco unting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract (ASU 2018-15), on July 1, 2018, the Company evaluates upfront costs including implementation, set-up or other costs (collectively, implementation costs) fo r hosting arrangements under the internal-use software framework. Costs related to preliminary project activities and post implementation activities are expensed as incurred, whereas costs incurred in the development stage are generally capitalized. Capita lized implementation costs are amortized on a straight-line basis over the expected term of the hosting arrangement, which includes consideration of the non-cancellable contractual term and reasonably certain renewals. As of March 31, 2020 and 2019, the ne t carrying value of capitalized implementation costs related to hosting arrangements that were incurred during the application development stage were $ 2.9 million and $ 1.6 million, respectively. These capitalized implementation costs will be amortized over the expected term of the arrangement and are amortized in the same line item in the consolidated statements of operations as the expense for fees for the associated hosti ng arrangement. Foreign Currency Translation The reporting currency of the Company is the U.S. dollar. The Company determines the functional currency for its non-U.S. subsidiaries by reviewing the currencies in which its respective operating activities occur. The functional currency of the Company’s non-U.S. subsidiaries is generally the local currency of each subsidiary. All assets and liabilities in the balance sheets of entities whose functional currency is a currency other than the U.S. dollar are translated into U.S. dollar equivalents at exchange rates as follows: (i) asset and liability accounts at period-end rates, (ii) income statement accounts at weighted-average exchange rates for the period, and (iii) shareholders’ equity accounts at historical exchange rates. Foreign exchange transaction gains and losses are included in foreign exchange (expense) income and other, net in the accompanying consolidated statements of operations. The effects of foreign currency translation adjustments are included as a component of accumulated other comprehensive loss in the accompanying consolidated balance sheets. Net Loss Per Ordinary Share The Company calculates basic and diluted net loss per ordinary share by dividing net loss by the weighted-average number of ordinary shares outstanding during the period. The Company has excluded the following potentially dilutive shares, which include share options outstanding, unvested RSUs and estimated employee share purchase plan ESPP shares, from the weighted-average number of ordinary shares outstanding as their inclusion in the computation for all periods would be anti-dilutive due to net losses incurred (in thousands): Year Ended March 31, 2020 2019 2018 Share options outstanding 6,271 6,209 6,230 Unvested RSUs 1,277 550 33 ESPP Shares 82 85 76 Advertising and Promotion Costs Expenses related to advertising and promotion of solutions is charged to sales and marketing expense as incurred. The Company incurred advertising expenses of $12.5 million, $12.5 million and $12.4 million during the years ended March 31, 2020, 2019 and 2018, respectively. Income Taxes The Company is subject to income tax in the United Kingdom, the United States and other internatio

Revenue and Deferred Revenue

Revenue and Deferred Revenue	12 Months Ended
	Mar. 31, 2020
Revenue From Contract With Customer [Abstract]
Revenue and Deferred Revenue	3. Revenue and Deferred Revenue Revenue recognized during the years ended March 31, 2020 and 2019 from amounts included in deferred revenue at the beginning of the period was approximately $158.8 million and $118.7 million, respectively. Revenue recognized during the years ended March 31, 2020 and 2019 from performance obligations satisfied or partially satisfied in previous periods was not material. Contracted revenue as of March 31, 2020 and 2019 that has not yet been recognized (contracted and not recognized) was $97.2 million and $86.0 million, respectively, which includes deferred revenue and non-cancellable amounts that will be invoiced and recognized as revenue in future periods and excludes contracts with an original expected length of one year or less. The Company expects 54% of contracted and not recognized revenue to be recognized over the next year, 44% in years two and three, with the remaining balance recognized thereafter.

Balance Sheet Components

Balance Sheet Components	12 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Balance Sheet Components	4. Balance Sheet Components Prepaid expenses and other current assets consist of the following: As of March 31, 2020 2019 Prepaid expenses $ 11,498 $ 11,259 Research and development investment tax credits 2,665 3,862 Lease incentive due from landlord — 8,900 Other current assets 1,982 1,850 Total prepaid expenses and other current assets $ 16,145 $ 25,871 Property and equipment, net, consists of the following: As of March 31, 2020 2019 Building and building improvements (1) $ — $ 47,001 Computer equipment (2) 131,920 112,277 Leasehold improvements 34,031 8,166 Furniture and fixtures 5,793 4,590 Office equipment 2,084 1,345 173,828 173,379 Less: Accumulated depreciation and amortization (1) (2) (88,650 ) (79,177 ) Property and equipment, net $ 85,178 $ 94,202 (1 ) As of March 31, 2019 U.S. build-to-suit facility $ 47,001 Less: Accumulated depreciation (5,164 ) $ 41,837 As of March 31, 2019, the U.S. build-to-suit facility includes company-funded building improvements of $5.2 million . (2) Includes property and equipment acquired under finance leases: As of March 31, 2020 2019 Computer equipment $ 4,714 $ 4,754 Less: Accumulated amortization (3,407 ) (2,228 ) $ 1,307 $ 2,526 Depreciation and amortization expense was $25.2 million, $25.2 million, and $17.5 million for the years ended March 31, 2020, 2019 and 2018, respectively. Depreciation and amortization expense in the years ended March 31, 2020, 2019 and 2018 included $1.2 million, $1.2 million and $0.9 million related to property and equipment acquired under capital leases. Accrued expenses and other current liabilities consists of the following: As of March 31, 2020 2019 Accrued payroll and related benefits $ 23,465 $ 21,198 Accrued taxes payable 5,809 5,305 Construction financing lease obligation — 2,670 Restructuring liability — 49 Other accrued expenses 12,333 15,087 Total accrued expenses and other current liabilities $ 41,607 $ 44,309 Other non-current liabilities consist of the following: As of March 31, 2020 2019 Deferred rent (3) $ — $ 10,218 Other non-current liabilities 4,386 5,363 Total other non-current liabilities $ 4,386 $ 15,581 (3 ) Upon the adoption of ASU 2016-02 on April 1, 2019, the Company recognized a ROUA and a lease liability on the balance sheet and therefore recognizes lease expense for operating leases on a straight-line basis over the lease term. See Note 9 for further details.

Restructuring

Restructuring	12 Months Ended
	Mar. 31, 2020
Restructuring And Related Activities [Abstract]
Restructuring	5. Restructuring In the fourth quarter of fiscal 2018, the Company ceased use of its Watertown, Massachusetts corporate office space and recorded a restructuring charge of $0.8 million. The fair value of the restructuring liability at the cease-use date of $1.1 million was determined by discounting estimated future cash flows, which consisted of remaining lease rentals and estimated sublease rentals that could be reasonably obtained for the property and was adjusted for the effects of deferred rent liabilities recognized under the lease of $0.3 million. The Company’s estimate of sublease rentals was based on a sublease agreement executed in the first quarter of fiscal 2019. In the second quarter of fiscal 2019, the Company recorded a revision to restructuring expense of $0.2 million related to the exit of its Watertown, Massachusetts corporate office space. The restructuring liability and any future changes in the estimate will be recorded in Restructuring in the consolidated statements of operations. The fair value measurement is classified within Level 3 of the fair value hierarchy wherein fair value is estimated using significant unobservable inputs

Acquisitions

Acquisitions	12 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Acquisitions	6. Acquisitions The following acquisitions have been accounted for as business combinations in accordance with ASC 805. The Company has recorded the assets acquired and liabilities assumed at their respective fair values as of the acquisition dates. Fiscal 2020 Acquisitions Segasec Labs Ltd. On January 3, 2020, the Company acquired Segasec Labs Ltd. (Segasec), a company incorporated under the laws of the State of Israel, that provides digital threat protection. Prior to the closing of the acquisition, the Company held an ownership interest of approximately 15.4% (see Note 8). The fair value of the previously held interest at the acquisition date approximated its’ original cost of $3.0 million. The Company acquired the remaining interest in Segasec for cash consideration of $24.2 million, net of cash acquired of $4.3 million. The preliminary purchase price allocation primarily consisted of $6.8 million of identifiable intangible assets and approximately $24.0 million of goodwill that is not deductible for tax purposes. The identifiable intangible assets primarily include developed technology of $6.7 million and customer relationships of $0.1 million, with estimated useful lives of 8.3 years and 6.3 years, respectively. The goodwill reflects the value of the synergies the Company expects to realize and the assembled workforce. The preliminary purchase price allocation is subject to finalization of amounts for potential indemnification adjustments. The significant intangible assets identified in the purchase price allocation discussed above include developed technology and customer relationships, which are amortized over their respective useful lives on a straight-line basis when the pattern in which their economic benefits will be consumed cannot be reliably determined. To value the developed technology asset, the Company utilized the income approach, specifically a discounted cash-flow method known as the multi-period excess earnings method. Customer relationships represent the underlying relationships with certain customers to provide ongoing services for products sold. The Company utilized the income approach, specifically the distributor method, a subset of the excess-earnings method to value the customer relationships. The significant assumptions used to estimate the value of the intangible assets included the discount rates, revenue growth rates, and technology migration curves. The Company has not presented pro forma results of operations for the Segasec acquisition because it is not material to the Company's consolidated results of operations, financial position, or cash flows. DMARC Analyzer B.V. On November 13, 2019, the Company acquired DMARC Analyzer B.V., a company organized under the laws of the Netherlands (DMARC Analyzer), for cash consideration of approximately $21.1 million, net of cash acquired of $0.4 million. DMARC Analyzer is a SaaS-based solution provider that offers user-friendly Domain-based Message Authentication, Reporting and Conformance (DMARC) setup, management and analysis. This acquisition further addresses threats at the email perimeter, inside the email network, and beyond their immediate purview. The preliminary purchase price allocation primarily consisted of $3.4 million of identifiable intangible assets and approximately $18.9 million of goodwill that is not deductible for tax purposes. The identifiable intangible assets primarily include developed technology of $3.2 million and customer relationships of $0.2 million, with estimated useful lives of 7.5 years and 5.5 years, respectively. The goodwill reflects the value of the synergies the Company expects to realize and the assembled workforce. The preliminary purchase price allocation is subject to finalization of amounts for potential indemnification adjustments. The significant intangible assets identified in the purchase price allocation discussed above include developed technology and customer relationships, which are amortized over their respective useful lives on a straight-line basis when the pattern in which their economic benefits will be consumed cannot be reliably determined. To value the developed technology asset, the Company utilized the income approach, specifically a discounted cash-flow method known as the multi-period excess earnings method. Customer relationships represent the underlying relationships with certain customers to provide ongoing services for products sold. The Company utilized the income approach, specifically the distributor method, a subset of the excess-earnings method to value the customer relationships. The significant assumptions used to estimate the value of the intangible assets included the discount rates, revenue growth rates, and technology migration curves. The Company has not presented pro forma results of operations for the DMARC Analyzer acquisition because it is not material to the Company's consolidated results of operations, financial position, or cash flows. Fiscal 2019 Acquisitions Solebit LABS Ltd. On July 31, 2018, the Company entered into a share purchase agreement (the Purchase Agreement) pursuant to which it acquired Solebit LABS Ltd. (Solebit), a company organized under the laws of the State of Israel, that provides security software. Solebit’s technology enhances security for the Company’s customers and adds to its ability to detect and prevent cyber-attacks, zero-day threats and malware across email and the web in real time. This acquisition further enhanced the Company’s cyber resilience platform architecture. The total purchase price of $96.5 million included cash payments of approximately $95.7 million. The following table summarizes the final purchase price allocation: Purchase consideration: Total cash paid, net of acquired cash $ 85,258 Cash and cash equivalents acquired 10,410 Fair value of previously held asset 828 Total purchase price consideration $ 96,496 Fair value of assets acquired and liabilities assumed: Cash and cash equivalents $ 10,410 Prepaid expenses and other current assets 76 Intangible assets 16,964 Goodwill 74,469 Total assets acquired 101,919 Accounts payable (18 ) Accrued expenses and other current liabilities (2,345 ) Deferred revenue (663 ) Other non-current liabilities (2,397 ) Total fair value of assets acquired and liabilities assumed $ 96,496 The significant intangible assets identified in the purchase price allocation discussed above include developed technology and customer relationships, which are amortized over their respective useful lives on a straight-line basis when the pattern in which their economic benefits will be consumed cannot be reliably determined. To value the developed technology asset, the Company utilized the income approach, specifically a discounted cash-flow method known as the multi-period excess earnings method. Customer relationships represent the underlying relationships with certain customers to provide ongoing services for products sold. The Company utilized the income approach, specifically the distributor method, a subset of the exces s-earnings method to value the customer relationships. The fair value of the assets acquired and liabilities assumed reflected in the tables above is less than the purchase price, resulting in the recognition of goodwill. The goodwill is not deductible for tax purposes and reflects the value of the synergies the Company expects to realize and the assembled workforce. The following table presents the estimated fair values and useful lives of the identifiable intangible assets acquired: Amount Estimated Useful Life (in years) Developed technology $ 16,689 10 Customer relationships 235 7 Trade names 40 1 Total identifiable intangible assets $ 16,964 Pro Forma Financial Information (unaudited) The following unaudited pro forma information presents the combined results of operations of the Company and Solebit for the years ended March 31, 2019 and 2018 as if the acquisition of Solebit had been completed on April 1, 2017. These pro forma financial results have been prepared for comparative purposes only and include certain adjustments that reflect pro forma results of operations such as fair value adjustments (step-downs) for deferred revenue, increased amortization for the fair value of acquired intangible assets and adjustments to eliminate transaction costs incurred by the Company and Solebit. The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and Solebit. Accordingly, these unaudited pro forma results are presented for informational purposes only and are not necessarily indicative of the results of operations that would have been achieved had the acquisition occurred as of April 1, 2017, nor are they intended to represent or be indicative of future results of operations (in thousands, except per share amounts): Year ended March 31, 2019 Revenue $ 340,824 Net loss (7,729 ) Basic and diluted net loss per share $ (0.13 ) Weighted average number of ordinary shares outstanding Basic and diluted 59,960 ATAATA, Inc. On July 9, 2018, the Company acquired ATAATA, Inc. (Ataata), a privately-owned company based in the United States, for cash consideration of approximately $23.2 million, net of cash acquired of $1.9 million. Ataata is a cybersecurity training and awareness platform designed to reduce human error in the workplace and help enable organizations to become more secure by changing the security culture of their employees. The acquisition allows customers to measure cyber risk training effectiveness by converting behavior observations into actionable risk metrics for security professionals. The addition of security awareness training and risk scoring and analysis strengthened the Company’s cyber resilience for email capabilities. The purchase price allocation primarily consisted of $1.5 million of identifiable intangible assets and approximately $22.6 million of goodwill that is not deductible for tax purposes. The identifiable intangible assets primarily include developed technology of $1.4 million and customer relationships of $0.1 million, with estimated useful lives of ten years and six years, respectively. The goodwill balance is primarily attributed to the expanded market opportunities when combining Ataata's awareness training technology with the Company’s other offerings. The Company has no t presented pro forma results of operations for the Ataata acquisition because it is not material to the Company's consolidated results of operations, financial position, or cash flows. Simply Migrate Ltd. On January 25, 2019, the Company acquired Simply Migrate Ltd., a provider of archive data migration technology, . With this acquisition, the Company expanded its data migration services with a rich portfolio of connectors, combined with a deeper experience in helping organizations get out of the business of managing expensive, unreliable legacy archives so they can move to a next-generation data protection strategy in the Mimecast cloud The purchase price allocation primarily consisted of $3.3 million of identifiable intangible assets, specifically developed technology, with an estimated useful life of eight years and approximately $4.3 million of goodwill that is not deductible for tax purposes. The goodwill balance is primarily attributed to the expanded market opportunities when combining Simply Migrate's archive data migration technology The Company has not presented pro forma results of operations for the Simply Migrate acquisition because it is not material to the Company's consolidated results of operations, financial position, or cash flows.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Mar. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	7. Goodwill and Intangible Assets The following table reflects goodwill activity in each of the periods presented: Year ended March 31, 2020 2019 Beginning balance $ 107,575 $ 5,631 Goodwill acquired 42,927 101,381 Effect of foreign exchange rates 23 563 Ending balance $ 150,525 $ 107,575 Purchased intangible assets consist of the following: Weighted- Average March 31, 2020 Remaining Gross Net Useful Life Carrying Accumulated Carrying (in years) Value Amortization Value Developed technology 8 $ 33,269 $ (4,547 ) $ 28,722 Customer relationships 5 771 (159 ) 612 Trade names N/A 41 (41 ) — Capitalized software and other (1) (2) 3 16,849 (7,789 ) 9,060 $ 50,930 $ (12,536 ) $ 38,394 Weighted- Average March 31, 2019 Remaining Gross Net Useful Life Carrying Accumulated Carrying (in years) Value Amortization Value Developed technology 9 $ 23,577 $ (1,707 ) $ 21,870 Customer relationships 6 455 (73 ) 382 Trade names 1 56 (34 ) 22 Capitalized software (1) 3 12,431 (4,082 ) 8,349 $ 36,519 $ (5,896 ) $ 30,623 (1) As of March 31, 2020 and 2019, the net carrying value of capitalized software and other includes $1.4 million and $0.5 million, respectively of costs capitalized related to video production costs. See Note 2 for further information. (2) As of March 31, 2020, the net carrying value of capitalized software and other includes $0.2 million of costs capitalized related to IP addresses. The Company recorded amortization expense of $7.0 million, $4.8 million and $1.5 million for the years ended March 31, 2020, 2019 and 2018, respectively. Amortization relating to developed technology and capitalized software was recorded within cost of revenue and amortization of customer relationships and trade names was recorded within sales and marketing expenses. Future estimated amortization expense of intangible assets as of March 31, 2020 is as follows: Purchased Intangible Capitalized Assets Software 2021 $ 3,827 $ 3,998 2022 3,827 2,701 2023 3,827 1,676 2024 3,772 395 2025 3,701 236 Thereafter 10,380 54 Total $ 29,334 $ 9,060

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurement	8. Fair Value Measurement The Company’s financial instruments include cash, cash equivalents, investments, accounts receivable, accounts payable, accrued expenses and borrowings under the Company’s long-term debt arrangements Strategic investments consist of non-controlling equity investments in privately held companies. As of March 31, 2020 and 2019, the Company did not hold any strategic investments (see Note 6). During the years ended March 31, 2020 and 2019, the Company held strategic investments of $3.0 million and $0.5 million, respectively, for which the Company did not have the ability to exercise significant influence. The Company elected the measurement alternative for these investments as they did not have readily determinable fair values. These non-marketable equity securities were included in other assets on the consolidated balance sheets and were carried at cost. Any adjustments resulting from impairment or observable price changes in orderly transactions for identical or similar investment of the same issuer are recorded within the consolidated statements of operations. In years ended March 31, 2020 and 2019, there were no adjustments to the carrying value of strategic investments resulting from impairments or observable price changes. The Company has evaluated the estimated fair value of financial instruments using available market information. The use of different market assumptions and/or estimation methodologies could have a significant effect on the estimated fair value amounts. Fair values determined using “Level 1 inputs” utilize unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access. Fair values determined using "Level 2 inputs" utilize quoted prices that are directly or indirectly observable. Fair values determined using “Level 3 inputs” utilize unobservable inputs for determining fair values of assets or liabilities that reflect an entity's own assumptions in pricing assets or liabilities. As of March 31, 2020 and 2019, the Company did not have any assets or liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3). The following table summarizes financial assets measured and recorded at fair value on a recurring basis in the accompanying consolidated balance sheets as of March 31, 2020 and 2019, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value: March 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1 Inputs) Significant Other Observable Inputs (Level 2 Inputs) Total Assets: Money market funds $ 17,495 $ — $ 17,495 March 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1 Inputs) Significant Other Observable Inputs (Level 2 Inputs) Total Assets: Money market funds $ 8,348 $ — $ 8,348 U.S. treasury securities — 1,994 1,994 Non-U.S. government securities — 7,981 7,981 Corporate securities — 25,966 25,966 Total assets $ 8,348 $ 35,941 $ 44,289

Leases

Leases	12 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Leases	9. Leases The Company has operating and finance leases for data centers, facilities, and certain equipment. The leases have remaining lease terms of less than a year to 10 years, some of which include options to extend the leases for up to 10 years. The Company recognizes lease expense for operating leases on a straight-line basis over the lease term. Variable costs, which are based on actual usage, are not included in the measurement of ROUAs and lease liabilities but are expensed when the event determining the amount of variable consideration to be paid occurs. Amortization expense of the ROUA for finance leases is recognized on a straight-line basis over the lease term and interest expense for finance leases is recognized based on the effective interest method using an incremental borrowing rate. Adoption of ASU 2016-02 resulted in the recording of additional net lease ROUA and lease liabilities of approximately $141.3 million and $154.7 million, respectively, as of April 1, 2019. Incremental borrowing rates as of April 1, 2019, the date the new standard was adopted, were used to calculate the present value of the Company’s lease portfolio as of that date. As noted below, leases previously identified as build-to-suit leases were derecognized pursuant to the transition guidance provided for build-to-suit leases in ASU 2016-02. The impact of the derecognition of the build-to-suit lease was a net reduction of $2.2 million to accumulated deficit as of April 1, 2019. The Company recorded the deferred tax impact associated with the cumulative-effect adjustment of adopting ASU 2016-02 to retained earnings with an equal and offsetting adjustment to our valuation allowance. The standard did not materially impact the consolidated net earnings or operating cash flows. The impact of the adoption of ASC 842 is as follows: Balance as of March 31, 2019 Adjustments Due to Adoption of ASC 842 Balance as of April 1, 2019 Assets Prepaid expenses and other current assets $ 25,871 $ (939 ) $ 24,932 Property and equipment, net 94,202 (30,963 ) 63,239 Operating lease right-of-use assets — 141,280 141,280 Other assets 5,156 (2,566 ) 2,590 Liabilities Accrued expenses and other current liabilities 44,309 (3,248 ) 41,061 Current portion of operating lease liabilities — 27,611 27,611 Construction financing lease obligations 36,650 (36,650 ) - Operating lease liabilities — 127,119 127,119 Other non-current liabilities 15,581 (10,192 ) 5,389 Shareholders' equity Accumulated deficit (83,632 ) 2,172 (81,460 ) The components of lease expense were as follows: Year ended March 31, 2020 Short-term lease cost $ 308 Variable lease cost 4,144 Operating lease cost 37,906 Finance lease cost: Amortization of lease assets 1,179 Interest on lease liabilities 93 Total finance lease cost $ 1,272 Supplemental cash flow information related to leases was as follows: Year ended March 31, 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash outflows from operating leases $ 32,816 Operating cash outflows from finance leases $ 74 Financing cash outflows from finance leases $ 844 Weighted-average remaining lease term and discount rate: As of March 31, 2020 Weighted-average remaining lease term (in years) Operating leases 6.46 Finance leases 1.31 Weighted-average discount rate Operating leases 4.74 % Finance leases 4.83 % Maturities of lease liabilities as of March 31, 2020 were as follows: Year Ending March 31, Operating Leases Finance Leases 2021 $ 36,231 $ 1,102 2022 27,653 326 2023 21,291 — 2024 14,741 — 2025 14,254 — Thereafter 43,516 — Total lease payments 157,686 1,428 Less: imputed interest (21,986 ) (47 ) Total lease liabilities $ 135,700 $ 1,381 As of March 31, 2020, the Company had no additional operating or finance leases that have not yet commenced. Rent expense related to the Company’s office facilities was $15.3 million, $5.3 million and $4.8 million for the years ended March 31, 2020, 2019 and 2018, respectively. As previously disclosed in the Company’s Annual Report on Form 10-K for the fiscal year ended March 31, 2019 and under the previous lease accounting standard, future minimum payments for capital leases, facility operating leases (including Lexington MA – U.S. build-to-suit lease) and data center operating leases as of March 31, 2019 were as follows: Year Ending March 31, Capital Leases Facility Leases Data Centers 2020 $ 918 $ 10,649 $ 21,216 2021 1,102 15,186 17,427 2022 326 14,111 13,010 2023 — 13,825 2,774 2024 — 13,686 356 Thereafter — 59,502 — Total minimum lease payments 2,346 $ 126,959 $ 54,783 Less: Amount representing interest (121 ) Present value of capital lease obligations 2,225 Less: Current portion (844 ) Long-term portion of capital lease obligations $ 1,381 Lexington, MA - U.S. Headquarters Prior to the adoption of ASU 2016-02, the Company established assets and liabilities for the estimated construction costs incurred under certain lease arrangements where it was considered the owner for accounting purposes only, or build-to-suit leases, to the extent it was involved in the construction of structural improvements or took construction risk prior to commencement of a lease. Upon occupancy of facilities under build-to-suit leases, the Company assessed whether these arrangements qualified for sales recognition under the sale-leaseback accounting guidance. In February 2017, the Company entered into a lease agreement for a new U.S. headquarters located in a building (the Building) under construction at 191 Spring Street, Lexington, Massachusetts (191 Spring Lease) and determined that it would account for the 191 Spring Lease as a build-to-suit lease as of March 31, 2017. In the year ended March 2018, the construction of the Building was substantially completed. The Company concluded that it did not meet the sale-leaseback criteria and the Company continued to be the deemed owner of the building for accounting purposes. Upon the adoption of ASU 2016-02, the Company derecognized the build-to-suit asset and related liability

Debt

Debt	12 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Debt	10. Debt In July 2018, the Company entered into that certain credit agreement (the Credit Agreement), dated as of July 23, 2018 by and among the Company, certain of the Company’s subsidiaries party thereto, as guarantors, certain financial institutions party thereto from time to time, as lenders, and JPMorgan Chase Bank, N.A., as administrative agent (the Administrative Agent). The Credit Agreement provided the Company with a $100.0 million senior secured term loan (the Term Loan) and a $50.0 million senior secured revolving credit facility (the Revolving Facility, and together with the Term Loan, the Credit Facility). Interest under the Credit Facility accrues at a rate between LIBOR plus 1.375% and LIBOR plus 1.875%, based on the Company’s ratio of indebtedness to earnings before interest, taxes, depreciation, amortization and certain other adjustments (Consolidated EBITDA). Based on this ratio, the effective interest rate as of March 31, 2020 and 2019 under the Credit Facility is LIBOR plus 1.375% and 1.625%, respectively. The term of the Credit Facility is five years, maturing on July 23, 2023. At the time the Company entered into the Credit Agreement, there was no outstanding debt. The Company was in compliance with all covenants as of March 31, 2020 and 2019. The Company allocated debt issuance costs for the Credit Facility on a pro-rata basis between the Term Loan and Revolving Facility. The debt issuance costs on the Term Loan are recorded as a reduction of debt and are amortized and recognized as additional interest expense over the life of the debt instrument using the effective interest method. The debt issuance costs on the Revolving Facility are recorded in other assets and are amortized and recognized as additional interest expense over the life of the Revolving Facility on a straight-line basis. As of March 31, 2020 and 2019, the balance of debt issuance costs recorded as a reduction of debt was $0.9 million and $1.3 million, respectively and the balance of debt issuance costs recorded in other assets was $0.5 million and $0.6 million, respectively. As of March 31, 2020 and 2019, the Company had $93.8 million and $98.1 million, respectively outstanding on the Term Loan and had no outstanding borrowings under the Revolving Facility. As of March 31, 2020 and 2019, total availability under the Revolving Facility was reduced by outstanding letters of credit of $2.0 million and $3.9 million, respectively. As of March 31, 2020 and 2019, total availability under the Revolving Facility was $48.0 million and $46.1 million, respectively. Future minimum principal payment obligations under the Term Loan are as follows: Year Ending March 31, Debt 2021 6,875 2022 9,375 2023 10,000 2024 67,500 Total minimum debt payments 93,750 Less: Debt issuance costs (919 ) Less: Current portion of long-term debt (6,573 ) Long-term debt $ 86,258

Related Party Transactions

Related Party Transactions	12 Months Ended
	Mar. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	11 . Related Party Transactions Certain of the Company’s shareholders and certain companies affiliated with our directors and executive officers were also customers of the Company during the periods included in the consolidated financial statements. Revenue recognized during the years ended March 31, 2020, 2019 and 2018 and accounts receivable outstanding as of March 31, 2020 and 2019 related to these transactions were not material.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Shareholders' Equity	12. Shareholders’ Equity The following ordinary shares were reserved for future issuance under the 2015 Plan, Historical Plans and ESPP (as defined below in Note 13): As of March 31, 2020 Options outstanding under share option plans 6,271,111 Unvested RSUs 1,276,840 Options and awards available for future grant under the 2015 Plan 9,992,607 Shares reserved for issuance under ESPP 748,903 Total authorized ordinary shares reserved for future issuance 18,289,461

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Share-Based Compensation	13. Share-Based Compensation For the years ended March 31, 2020, 2019 and 2018, all grants of share-based awards have been made under the Mimecast Limited 2015 Share Option and Incentive Plan (the 2015 Plan) and the 2015 Employee Share Purchase Plan (the ESPP). Additionally, the Company has three pre-IPO share-based compensation plans including the Mimecast Limited 2007 Key Employee Share Option Plan (the 2007 Plan), the Mimecast Limited 2010 EMI Share Option Scheme (the 2010 Plan), and the Mimecast Limited Approved Share Option Plan (the Approved Plan) (the 2007 Plan, the 2010 Plan and the Approved Plan, collectively, the Historical Plans). Subsequent to November 19, 2015, the IPO date, no further grants under the Historical Plans were permitted. The 2015 Plan allows the compensation committee of the board of directors to make equity-based incentive awards to our officers, employees, non-employee directors and consultants. Initially a total of 5.5 million ordinary shares were reserved for the issuance of awards under the 2015 Plan. This number is subject to adjustment in the event of a share split, share dividend or other change in our capitalization. The 2015 Plan provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1 st Under the 2015 Plan, the share option price may not be less than the fair market value of the ordinary shares on the date of grant and the term of each share option may not exceed 10 years from the date of grant. Share options typically vest over 4 years, but vesting provisions can vary based on the discretion of the board of directors. The Company settles share option exercises and RSU releases under the 2015 Plan through newly issued shares. The Company’s ordinary shares underlying any awards that are forfeited, canceled, withheld upon ex ercise of an option, or settlement of an award to cover the exercise price or tax withholding, or otherwise terminated other than by exercise will be added back to the shares available for issuance under the 2015 Plan. Initially, a total of 1.1 million shares of the Company's ordinary shares were reserved for future issuance under the ESPP. This number is subject to change in the event of a share split, share dividend or other change in capitalization. The ESPP may be terminated or amended by the board of directors at any time. The ESPP permits eligible employees to purchase shares by authorizing payroll deductions from 1% to 10% of his or her eligible compensation during each six-month Share-based compensation expense recognized under the 2015 Plan, Historical Plans and ESPP in the accompanying consolidated statements of operations was as follows: Year ended March 31, 2020 2019 2018 Cost of revenue $ 3,445 $ 1,684 $ 1,053 Research and development 10,900 6,199 2,555 Sales and marketing 13,141 7,856 4,477 General and administrative 12,058 10,215 3,649 Total share-based compensation expense $ 39,544 $ 25,954 $ 11,734 In certain situations, the board of directors has approved modifications to employee share option agreements, including acceleration of vesting or the removal of exercise restrictions for share options for which the service-based vesting has been satisfied, which resulted in additional share-based compensation expense. The total modification expense recognized in the years ended March 31, 2020, 2019 and 2018 was $0.1 million, $3.2 million and $0.5 million, respectively. Share Options Share option activity under the 2015 Plan and Historical Plans for the year ended March 31, 2020 was as follows: Number of Awards Weighted Exercise Price (1) Weighted Remaining Contractual Term (in years) Aggregate Intrinsic Outstanding as of March 31, 2019 6,208,964 $ 23.47 7.58 $ 148,313 Options granted 2,016,318 $ 46.29 Options exercised (1,359,903 ) $ 14.81 Options forfeited and cancelled (594,268 ) $ 35.39 Outstanding as of March 31, 2020 6,271,111 $ 31.61 7.55 $ 47,621 Exercisable as of March 31, 2020 2,602,224 $ 20.43 6.24 $ 40,224 (1) Certain of the Company’s option grants have an exercise price denominated in British pounds. The weighted-average exercise price at the end of each reporting period was translated into U.S. dollars using the exchange rate at the end of the period. The weighted-average exercise price for the options granted, exercised, forfeited and cancelled was translated into U.S. dollars using the exchange rate at the applicable date of grant, exercise, forfeiture or cancellation, as appropriate. The total intrinsic value of options exercised for the years ended March 31, 2020, 2019 and 2018 was $40.0 million, $66.4 million and $74.2 million, respectively. Total cash proceeds from option exercises for the years ended March 31, 2020, 2019 and 2018 were $20.1 million, $21.4 million and $15.6 million, respectively. As of March 31, 2020, there was approximately $53.7 million of unrecognized share-based compensation related to unvested share-based awards subject to service-based vesting conditions, which is expected to be recognized over a weighted-average period of 2.68 years. ESPP In the years ended March 31, 2020, 2019 and 2018, the Company issued 156 thousand, 130 thousand and 64 thousand shares, respectively, in connection with its ESPP offerings and received cash proceeds of $4.9 million, $3.3 million and $1.4 million, respectively. In the years ended March 31, 2020, 2019 and 2018, the Company recognized $1.8 million, $1.3 million and $0.7 million of share-based compensation expense under the ESPP, respectively. RSUs The Company grants RSUs to its non-employee directors and its employees. Non-employee directors receive an initial RSU grant upon joining the board of directors that vests over three years and an annual grant each year thereafter that vests fully on the one-year anniversary of the grant date. RSUs granted to employees generally vest in four equal annual installments. RSU activity under the 2015 Plan for the year ended March 31, 2020 was as follows: Number of Shares Weighted Average Grant Date Fair Value Intrinsic Value (in thousands) (1) Unvested RSUs as of March 31, 2019 549,853 $ 37.15 $ 26,036 RSUs granted 1,015,290 $ 46.17 RSUs vested (161,450 ) $ 37.04 RSUs forfeited (126,853 ) $ 44.08 Unvested RSUs as of March 31, 2020 1,276,840 $ 43.64 $ 45,072 (1) As of March 31, 2020 and 2019, the intrinsic value of unvested shares was calculated based on the closing price of the Company’s ordinary shares on the NASDAQ Global Select Market on March 31, 2020 and 2019, respectively, multiplied by the number of unvested RSUs. As of March 31, 2020, there was approximately $43.5 million of unrecognized share-based compensation expense related to unvested RSUs, which is expected to be recognized over a weighted-average period of 2.97 years.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	14. Commitments and Contingencies Litigation During fiscal 2019 and 2020, the Company engaged in discussions with a non-practicing patent entity (NPE) regarding the entity’s patented technology and allegations regarding the Company’s past infringement of that technology. On September 30, 2019, the Company entered into confidential global patent license agreements with the NPE and certain of its affiliates that provided patent licenses to the Company related to the NPE’s global patent portfolio, resolved all claims of past infringement and provided mutual covenants not to sue for a certain number of years. Under the terms of the patent license agreements, the Company made an aggregate payment of $5.9 million to the NPE. The Company evaluated the transaction as a multiple-element arrangement and allocated the payment of $5.9 million to each identifiable element using its relative fair value. Based on estimates of fair value, the Company determined that the primary benefit of the arrangement is the avoidance of litigation costs and the release of any potential past infringement claims, with a portion of the value attributable to future use or benefit of the global patent license. In the fiscal years ended March 31, 2020 and 2019, the Company recorded expense of $2.7 million and $1.0 million, respectively within general and administrative expenses. The remaining $2.2 million is being amortized over its expected useful life of 3.5 years. On September 10, 2019, ZapFraud, Inc. (ZapFraud), filed a complaint in the U.S. District Court for the District of Delaware against the Company’s wholly owned subsidiaries, Mimecast North America, Inc., Mimecast Services Limited and Mimecast UK Limited. The complaint alleges that certain elements of the Company’s email security technology infringe a patent held by ZapFraud. ZapFraud seeks an award for damages in an unspecified amount, attorney’s fees and injunctive relief. On November 22, 2019, the Company filed a Motion to Dismiss for Failure to State a Claim. The Company has requested that a hearing be held on this motion, but no court date has been set. On April 24, 2020, ZapFraud amended its complaint by alleging that the Company’s email security technology infringes an additional patent that was recently issued to ZapFraud. The Company plans to amend its Motion to Dismiss for Failure to State a Claim to address this additional patent. This litigation is in its very early stages. As a result, neither the ultimate outcome of this litigation nor an estimate of a probable loss or any reasonably possible losses can be assessed at this time. The Company intends to defend the lawsuit vigorously. Regardless of the outcome, litigation can have an adverse impact on the Company because of defense and potential settlement costs, diversion of management resources and other factors. From time to time, the Company may be involved in legal proceedings and subject to claims in the ordinary course of business. Although the results of these proceedings and claims cannot be predicted with certainty, the Company does not believe the ultimate cost to resolve these matters would individually, or taken together, have a material adverse effect on the Company’s business, operating results, cash flows or financial condition. Reg ardless of the outcome, such proceedings can have an adverse impact on the Company because of defense and settlement costs, diversion of resources and other factors, and there can be no assurances that favorable outcomes will be obtained . Except as described above, t he Company was not subject to any material legal proceedings during the years ended March 31, 2020, 2019 and 2018, and, to the best of its knowledge, except as described above, no material legal proceedings are currently pending or threatened. Indemnification The Company typically enters into indemnification agreements with customers in the ordinary course of business. Pursuant to these agreements, the Company indemnifies and agrees to reimburse the indemnified party for losses suffered or incurred as a result of claims of intellectual property infringement. These indemnification agreements are provisions of the applicable customer agreement. Based on when clients first sign an agreement for the Company’s service, the maximum potential amount of future payments the Company could be required to make under certain of these indemnification agreements is unlimited. Based on historical experience and information known as of March 31, 2020, the Company has not incurred any costs for the above indemnities. In certain circumstances, the Company warrants that its services will perform in all material respects in accordance with its standard published specification documentation in effect at the time of delivery of the services to the customer for the term of the agreement. To date, the Company has not incurred significant expense under its warranties and, as a result, the Company believes the estimated fair value of these agreements is immaterial.

Employee benefit plans

Employee benefit plans	12 Months Ended
	Mar. 31, 2020
Postemployment Benefits [Abstract]
Employee Benefit Plans	15. Employee Benefit Plans The Company maintains a defined contribution savings plan under Section 401(k) of the U.S. Internal Revenue Code of 1986 (the 401(k) Plan), covering all U.S. employees who satisfy certain eligibility requirements. The 401(k) Plan allows each participant to defer a percentage of their eligible compensation subject to applicable annual limits pursuant to the limits established by the Internal Revenue Service. The Company’s matching contributions were $1.6 million and $1.2 million for the year ended March 31, 2020 and 2019, respectively. For the year ended March 31, 2018 the Company did not make any matching or profit-sharing contributions. The Company contributes to a defined contribution savings plan for its employees in the United Kingdom who satisfy certain eligibility requirements. The plan allows each participant to defer a percentage of their compensation and the Company contributes an additional 3.5% of all wages for those employees in the scheme on a monthly basis. The Company’s contributions were $1.9 million, $1.5 million and $0.5 million for the years ended March 31, 2020, 2019, and 2018, respectively. Beginning in fiscal year 2020, the Company contributes to defined contribution savings plans for its employees in South Africa, Germany, and the Netherlands, who satisfy certain eligibility requirements. The plans allow each participant to defer a percentage of their compensation and the Company contributes an additional 5%, 3%, and 3%, respectively of all wages for those employees in the scheme on a monthly basis. The Company’s contributions were $0.6 million for the year ended March 31, 2020.

Segment and Geographic Informat

Segment and Geographic Information	12 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Segment and Geographic Information	16. Segment and Geographic Information Disclosure requirements about segments of an enterprise and related information establishes standards for reporting information regarding operating segments in annual financial statements and requires selected information of those segments to be presented in interim financial reports issued to shareholders. Operating segments are defined as components of an enterprise about which separate discrete financial information is available that is evaluated regularly by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company’s chief operating decision maker is the chief executive officer. The Company and the chief executive officer view the Company’s operations and manage its business as one operating segment. Geographic Data The Company allocates, for the purpose of geographic data reporting, its revenue based upon the location of the contracting subsidiary. Total revenue by geographic area was as follows: Year ended March 31, 2020 2019 2018 United States $ 219,423 $ 169,286 $ 128,503 United Kingdom 123,620 103,900 81,720 South Africa 51,549 46,275 39,425 Other 32,371 20,916 12,249 Total revenue $ 426,963 $ 340,377 $ 261,897 Property and equipment, net by geographic location consisted of the following: As of March 31, 2020 2019 United States (1) $ 39,193 $ 62,455 United Kingdom 29,644 17,402 South Africa 7,093 6,170 Other 9,248 8,175 Total $ 85,178 $ 94,202 (1) Includes construction costs capitalized under financing lease obligations related to the Company’s U.S. build-to-suit facility of $41.8 million as of March 31, 2019.

Income Taxes

Income Taxes	12 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	17. Income Taxes Income (loss) before income taxes consists of the following: Year ended March 31, 2020 2019 2018 United Kingdom $ (20,528 ) $ (4,626 ) $ (15,939 ) Foreign 20,687 (374 ) 6,258 Income (loss) before income taxes $ 159 $ (5,000 ) $ (9,681 ) The provision for income taxes in the accompanying consolidated financial statements is comprised of the following: As of March 31, 2020 2019 2018 Current tax expense: Domestic $ — $ — $ — Foreign 2,939 3,493 2,597 Total current tax expense 2,939 3,493 2,597 Deferred tax expense: Domestic — (578 ) — Foreign (580 ) (914 ) 108 Total deferred tax (benefit) expense (580 ) (1,492 ) 108 Total provision for income taxes $ 2,359 $ 2,001 $ 2,705 The reconciliation of the United Kingdom statutory tax rate to the Company’s effective tax rate included in the accompanying consolidated statements of operations is as follows: Year ended March 31, 2020 2019 2018 Tax at statutory rate 19.0 % 19.0 % 19.0 % U.S. state taxes, net of federal 558.0 31.1 14.1 Foreign rate differential 291.5 26.3 36.8 Meals and entertainment 432.6 (11.4 ) (3.1 ) Branch (income) loss (69.9 ) (0.6 ) 0.4 Share-based compensation (2,341.9 ) 172.3 105.3 Tax credits (375.5 ) 7.7 8.1 Unremitted earnings 101.3 (3.8 ) (1.2 ) Change in valuation allowance (1,456.8 ) (249.9 ) (110.7 ) Deferred tax true-ups 116.2 (3.5 ) 8.4 Tax reserves 3,147.4 (4.9 ) (21.5 ) Provision to return 37.6 (0.1 ) 0.4 Withholding taxes 323.5 (2.6 ) (3.5 ) Non-deductible expenses 197.7 (5.2 ) (2.4 ) Deferred tax rate change 473.1 (6.3 ) (77.8 ) Acquisition-related costs 91.7 (7.6 ) — Foreign exchange (59.5 ) — — Other (2.4 ) (0.5 ) (0.2 ) Effective Tax Rate 1,483.6 % (40.0 )% (27.9 )% Although the Company’s parent entity is organized under Jersey law, our affairs are, and are intended to be, managed and controlled in the United Kingdom for tax purposes. Therefore, the Company is resident in the United Kingdom for tax purposes. The Group’s parent entity is domiciled in the United Kingdom and its earnings are subject to 19% statutory tax rates for the years ended March 31, 2020, 2019 and 2018, respectively. The Company’s effective tax rate differs from the statutory rate each year primarily due to windfall tax benefits on equity award exercises, the valuation allowance maintained against the Company’s net deferred tax assets, the jurisdictional earnings mix, tax credits, withholding taxes, tax reserves, and other permanent differences primarily related to non-deductible expenses. Deferred tax assets and liabilities reflect the net tax effects of net operating loss carryovers and the temporary differences between the assets and liabilities carrying value for financial reporting and the amounts used for income tax purposes. T As of March 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 30,879 $ 35,120 Share-based compensation 9,501 5,687 Deferred revenue 2,315 1,761 Fixed assets 4,718 4,187 Lease liability 30,890 11,748 Accrued compensation 1,786 1,211 Deferred rent — 320 Income tax credits 2,311 1,833 Other 2,042 1,648 Gross deferred tax assets 84,442 63,515 Deferred tax liabilities: Fixed assets (7,414 ) (13,855 ) Unremitted earnings (362 ) (320 ) Intangible assets (6,453 ) (4,818 ) Capitalized commissions (9,751 ) (7,606 ) Right-of-use asset (26,498 ) — Other (2,145 ) (606 ) Gross deferred tax liabilities (52,623 ) (27,205 ) Valuation allowance (34,224 ) (38,318 ) Deferred tax liabilities, net $ (2,405 ) $ (2,008 ) In assessing the ability to realize the Company’s net deferred tax assets, management considers various factors including taxable income in carryback years, future reversals of existing taxable temporary differences, tax planning strategies, and future taxable income projections to determine whether it is more likely than not that some portion or all of the net deferred tax assets will not be realized. Based on the negative evidence, including the worldwide cumulative losses that the Company has incurred, the Company has determined that the uncertainty regarding realizing its deferred tax assets is sufficient to warrant the need for a full valuation allowance against its worldwide net deferred tax assets. The $4.1 million net decrease in the valuation allowance from 2019 to 2020 is primarily due to the operating results of our entities against which a valuation allowance is maintained as well as the impact of share-based compensation including windfall tax deductions. During the fourth quarter of fiscal 2020, the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) was enacted in the United States. The CARES Act provides numerous tax provisions and other stimulus measures, including temporary changes regarding the prior and future utilization of net operating losses, temporary suspension of certain payment requirements for the employer portion of Social Security taxes, technical corrections from prior tax legislation for tax depreciation of certain qualified improvement property, and the creation of certain refundable employee retention credits. The Company evaluated the provisions of the CARES Act and does not anticipate the associated impacts, if any, will have a material effect on the Company’s provision for income taxes for the year ended March 31, 2020. As of March 31, 2020, the Company had U.K. net operating loss carryforwards of approximately $70.2 million that do not expire. As of March 31, 2020, the Company had U.S. federal net operating loss carryforwards of approximately $69.4 million. U.S. federal net operating loss carryforwards generated through March 31, 2018 of approximately $51.4 million expire at various dates through 2038, and U.S. federal net operating loss carryforwards generated in the tax years beginning after March 31, 2018 of approximately As of March 31, 2020, the Company had Israeli net operating loss carryforwards of approximately $9.7 million that do not expire. As of March 31, 2020, the Company had Dutch net operating loss carryforwards of approximately $0.8 million that expire at various dates from 2026 through 2028. As of March 31, 2020, the Company had an Israeli income tax credit carryforward of $0.9 million that expire at various dates from 2023 through 2025 Under Section 382 of the U.S. Interna l Revenue Code, if a corporation undergoes an ownership change, the corporation’s ability to use its pre-change net operating loss carryforwards to offset its post-change income and taxes may be limited. In general, an ownership change occurs if there is a 50 percent cumulative change in ownership of the Company over a rolling three-year period. Similar rules may apply under U.S. state tax laws. The Company believes that it has experienced an ownership change in the past and may experience ownership changes in the future resulting from future transactions in our share capital, some of which may be outside the Company’s control. The Company’s ability to utilize its net operating loss carryforwards or other tax attributes to offset U.S. federal and state taxab le income in the future may be subject to future limitations. The most recent analysis of the Company’s historical ownership changes was completed through March 31, 2020. Based on the analysis, the Company does not anticipate a significant limitation on th e utilization of the Company’s tax attributes. As of March 31, 2020 and 2019, the Company had liabilities for uncertain tax positions of $10.4 million and $6.0 million, respectively, none of which, if recognized, would materially impact the Company’s effective tax rate. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: Year ended March 31, 2020 2019 Beginning balance $ 6,016 $ 6,164 Additions based on tax positions related to current year 535 164 Additions for tax positions of prior years 4,235 231 Reductions due to change in foreign exchange rate (431 ) (301 ) Expiration of statutes of limitation — (165 ) Reductions due to settlements with tax authorities — (77 ) Ending balance $ 10,355 $ 6,016 Interest and penalty charges, if any, related to uncertain tax positions are classified as income tax expense in the accompanying consolidated statements of operations. As of March 31, 2020 and 2019, the Company had immaterial accrued interest or penalties related to uncertain tax positions. The Company is subject to taxation in the United Kingdom and several foreign jurisdictions. As of March 31, 2020, the Company is no longer subject to examination by taxing authorities in the United Kingdom for years prior to March 31, 2019. The significant foreign jurisdictions in which the Company operates are no longer subject to examination by taxing authorities for years prior to March 31, 2017. In addition, net operating loss carryforwards in certain jurisdictions may be subject to adjustments by taxing authorities in future years when they are utilized. The Company had approximately $47.8 million of unremitted foreign earnings as of March 31, 2020. Income taxes have been provided on approximately $14.2 million of the unremitted foreign earnings. Income taxes have not been provided on approximately $33.5 million of unremitted foreign earnings because they are considered to be indefinitely reinvested. The tax payable on the earnings that are indefinitely reinvested would be immaterial.

Subsequent Events

Subsequent Events	12 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	18. Subsequent Events S hare Option and RSU Grants On April 1, 2020, the Company granted approximately 0.8 million share options and 1.6 million RSUs to its employees as part of its annual share-based award grant. The grant date fair value per share for share options and RSUs was $14.29 and $33.38, respectively.

Quarterly Results of Operations

Quarterly Results of Operations Data (unaudited)	12 Months Ended
	Mar. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results of Operations Data (unaudited)	19. Quarterly Results of Operations Data (unaudited) The following tables set forth our unaudited quarterly consolidated statements of operations for each of the eight quarters in the period ended March 31, 2020. The Company has prepared the quarterly consolidated statements of operations data on a basis consistent with the audited consolidated financial statements included elsewhere in this Annual Report on Form 10-K. In the opinion of management, the financial information reflects all adjustments, consisting only of normal recurring adjustments, which management considers necessary for a fair presentation of this data. This information should be read in conjunction with the audited consolidated financial statements and related notes included elsewhere in this Annual Report on Form 10-K. The results of historical periods are not necessarily indicative of the results to be expected for any future period. Quarter ended Mar 31, Dec 31, Sep 30, Jun 30, Mar 31, Dec 31, Sep 30, Jun 30, 2020 2019 2019 2019 2019 2018 2018 2018 (in thousands, except per share amounts) Revenue $ 114,217 $ 110,158 $ 103,357 $ 99,231 $ 92,193 $ 87,611 $ 82,169 $ 78,404 Gross profit 84,891 81,703 77,223 73,764 67,491 64,353 60,231 57,428 Income (loss) from operations 5,125 1,629 (18 ) (4,438 ) 207 1,572 (909 ) (2,089 ) Net income (loss) 2,525 206 (921 ) (4,010 ) (1,930 ) 458 (2,058 ) (3,471 ) Net income (loss) per ordinary share: Basic $ 0.04 $ 0.00 $ (0.01 ) $ (0.07 ) $ (0.03 ) $ 0.01 $ (0.03 ) $ (0.06 ) Diluted $ 0.04 $ 0.00 $ (0.01 ) $ (0.07 ) $ (0.03 ) $ 0.01 $ (0.03 ) $ (0.06 ) Weighted-average number of ordinary shares outstanding: Basic 62,636 62,189 61,829 61,444 60,733 60,141 59,800 59,175 Diluted 64,382 63,996 61,829 61,444 60,733 62,537 59,800 59,175

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB). The Company reclassified certain amounts within its consolidated statements of cash flows to conform to current period presentation. The reclassifications include $0.3 million and $0.1 million from proceeds from issuance of ordinary shares to withholding taxes related to net share settlement of ESPP purchases and vesting of RSUs for the years ended March 31, 2019 and 2018, respectively. These reclassifications had no impact on the Company’s previously reported results of operations or its balance sheets.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of income and expenses during the reporting period. Significant estimates relied upon in preparing these consolidated financial statements include revenue recognition, variable consideration, valuation at fair value of assets acquired or sold, including intangibles, goodwill, tangible assets, and liabilities assumed, amortization perio ds, expected future cash flows used to evaluate the recoverability of long-lived assets, contingent liabilities, determination of incremental borrowing rates, restructuring liabilities, expensing and capitalization of research and development costs for int ernal-use software, the determination of the fair value of share-based awards issued, the average period of benefit associated with costs capitalized to obtain revenue contracts and the recoverability of the Company’s net deferred tax assets and related va luation allowance. Although the Company regularly assesses these estimates, actual results could differ materially from these estimates. The Company bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances. Actual results may differ from management’s estimates if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. Changes in estimates are recorded in the period in which they become known.
Subsequent Events Considerations	Subsequent Events Considerations The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated as required. See Note 18.
Cash, Cash Equivalents and Investments	Cash, Cash Equivalents and Investments The Company considers all highly liquid instruments purchased with an original maturity date of 90 days or less from the date of purchase to be cash equivalents. Cash and cash equivalents consist of cash on deposit with banks, amounts held in interest-bearing money market funds and investments with maturities of 90 days or less from the date of purchase. Cash equivalents are carried at cost, which approximates their fair market value. Investments not classified as cash equivalents are presented as either short-term or long-term investments based on both their stated maturities as well as the time period the Company intends to hold such securities. The Company determines the appropriate classification of investments at the time of purchase and reevaluates such designation at each balance sheet date. The Company adjusts the cost of investments for amortization of premiums and accretion of discounts to maturity. The Company includes such amortization and accretion in interest income in the consolidated statements of operations. The Company did not hold any debt investments as of March 31, 2020. When the Company holds debt investments classified as available-for-sale pursuant to ASC 320, Investments – Debt Securities, The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than its amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the investment, or if it is more likely than not that the Company will be required to sell the investment before recovery of the amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, compliance with the Company’s investment policy, the severity and the duration of the impairment and changes in value subsequent to the end of the period. As of March 31, 2020, the Company did not hold any investments. As of March 31, 2019, the aggregate fair value of investments held by the Company in an unrealized loss position for less than twelve months was $10.0 million. For the years ended March 31, 2020, 2019 and 2018, the Company determined that no other-than-temporary impairments were required to be recognized in the consolidated statements of operations. The following is a summary of cash, cash equivalents and investments as of March 31, 2020 and March 31, 2019: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value March 31, 2020: Cash and cash equivalents due in 90 days or less $ 173,958 $ — $ — $ 173,958 Total cash, cash equivalents and investments $ 173,958 $ — $ — $ 173,958 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value March 31, 2019: Cash and cash equivalents due in 90 days or less $ 137,576 $ — $ — $ 137,576 Investments: U.S. treasury securities due in one year or less 1,993 1 — 1,994 Non-U.S. government securities due in one year or less 7,969 12 — 7,981 Corporate securities due in one year or less 25,951 24 (9 ) 25,966 Total investments 35,913 37 (9 ) 35,941 Total cash, cash equivalents and investments $ 173,489 $ 37 $ (9 ) $ 173,517
Revenue Recognition	Revenue Recognition Revenue Recognition Policy The Company recognizes revenue upon transfer of control of promised products or services to customers in an amount that reflects the consideration the Company expects to receive in exchange for those products or services. To achieve the core principle of ASC 606, the Company performs the following steps: 1) Identify the contract(s) with a customer; 2) Identify the performance obligations in the contract; 3) Determine the transaction price; 4) Allocate the transaction price to the performance obligations in the contract; and 5) Recognize revenue when (or as) the Company satisfies a performance obligation. The Company derives its revenue from two sources: (1) subscription revenue, which are comprised of subscription fees from customers accessing the Company’s cloud services and from customers purchasing additional support beyond the standard support that is included in the basic subscription fees; and (2) related professional services and other revenue, which consists primarily of certain performance obligations related to set-up, ingestion, consulting and training fees. In the years ended March 31, 2020, 2019 and 2018, subscription revenue made up the substantial majority of the Company’s revenue and professional services and other revenue made up less than 5% of the Company’s revenue. The Company’s subscription arrangements provide customers the right to access the Company’s hosted software applications. Customers do not have the right to take possession of the Company’s software during the hosting arrangement. The Company sells its products and services directly through the Company’s sales force and also indirectly through third-party resellers. In accordance with the provisions of ASC 606, the Company has considered certain factors in determining whether the end-user or the third-party reseller is the customer in arrangements involving resellers. The Company concluded that in the majority of transactions with resellers, the reseller is the customer. In these arrangements, the Company considered that it is the reseller, and not the Company, that has the relationship with the end-user. Specifically, the reseller has the ability to set pricing with the end-user and the credit risk with the end-user is borne by the reseller. Further, the reseller is not obligated to report its transaction price with the end-user to the Company, and in the majority of transactions, the Company is unable to determine the amount paid by the end-user customer to the reseller in these transactions. As a result of such considerations, revenue for these transactions is presented in the accompanying consolidated statements of operations based upon the amount billed to the reseller. For transactions where the Company has determined that the end-user is the ultimate customer, revenue is presented in the accompanying consolidated statements of operations based on the transaction price with the end-user. The Company recognizes subscription and support revenue ratably over the term of the contract, typically one year in duration, beginning on the date the customer is provided access to the Company’s service. For performance obligations related to set-up and ingestion, including implementation assistance and data migration services, respectively, the Company recognizes revenue using output measures of performance that reflect the transfer of promised services to the customer consistent with progress to completion. The Company considers training, consulting, and other professional services contracts as separate performance obligations and recognizes revenue using output measures of performance as services are completed. Amounts that have been invo iced are recorded in accounts receivable and in deferred revenue or revenue, depending on whether the revenue recognition criteria have been met. The Company primarily bills and collects payments from customers for its services in advance on a monthly and annual basis. In some instances, the Company receives non-refundable upfront payments for activities that do not constitute a promise to transfer a service and therefore are considered administrative tasks, not separate performance obligations. The upfront payments are evaluated to determine whether a material right to a discount upon renewal of the subscription exists. When the Company concludes a material right does not exist, the Company recognizes revenue related to the upfront payment over the initial contract term. When the Company concludes a material right does exist, the Company recognizes revenue related to the upfront payment, under the look-through method, over the estimated customer benefit period, which has been determined to be six years. All of the Company’s performance obligations, and associated revenue, are generally transferred to customers over time, with the exception of training, consulting and other professional services, which are generally transferred to the customer at a point in time. Revenue is presented net of any taxes collected from customers. Some of the Company’s contracts with customers contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative standalone selling price basis. The Company determines the standalone selling prices based on the Company’s overall pricing objectives, taking into consideration market conditions and other factors, including the value of the Company’s contracts, the products sold, customer demographics, the Company’s sales channel, and the number and size of users within the Company’s contracts. Deferred revenue primarily consists of billings or payments received in advance of revenue recognition from subscription and other services described above and is recognized as the revenue recognition criteria are met. Deferred revenue that is expected to be recognized during the succeeding twelve-month period is recorded as current deferred revenue and the remaining portion is recorded as non-current in the accompanying consolidated balance sheets. Deferred Cost Policy T he Company capitalizes incremental costs of obtaining revenue contracts, which primarily consist of commissions paid to its sales representatives. The Company amortizes these commissions over six years on a systematic basis, consistent with the pattern of transfer of the goods or services to which the asset relates. Six years represents the estimated benefit period of the customer relationship taking into account factors such as peer estimates of technology lives and customer lives as well as the Company's own historical data. No commissions are paid related to contract renewals. The current and noncurrent portions of deferred commissions are included in deferred contract costs, net, and deferred contract costs, net of current portion, respectively, in the accompanying consolidated balance sheets. Revenue recognized during the years ended March 31, 2020 and 2019 from amounts included in deferred revenue at the beginning of the period was approximately $158.8 million and $118.7 million, respectively. Revenue recognized during the years ended March 31, 2020 and 2019 from performance obligations satisfied or partially satisfied in previous periods was not material.
Cost of Revenue	Cost of Revenue Cost of revenue primarily consists of expenses related to supporting and hosting the Company’s product offerings and delivering professional services. These costs include salaries, benefits, incentive compensation and share-based compensation expense related to the management of the Company’s data centers, customer support team and the Company’s professional services team. In addition to these costs, the Company incurs third-party service provider costs such as data center and networking expenses, allocated overhead, amortization of capitalized software and acquired
Concentration of Credit Risk and Off-Balance Sheet Risk	Concentration of Credit Risk and Off-Balance Sheet Risk The Company has no off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments, which potentially subject the Company to concentrations of credit risk, consist primarily of cash and cash equivalents, investments and accounts receivable. The Company maintains its cash, cash equivalents and investments with major financial institutions of high-credit quality. Although the Company deposits its cash with multiple financial institutions, its deposits, at times, may exceed federally insured limits. Credit risk with respect to accounts receivable is dispersed due to our large number of customers. The Company’s accounts receivable are derived from revenue earned from customers primarily located in the United States, the United Kingdom, and South Africa. The Company generally does not require its customers to provide collateral or other security to support accounts receivable. Credit losses historically have not been significant and the Company generally has not experienced any material losses related to receivables from individual customers, or groups of customers. Due to these factors, no additional credit risk beyond amounts provided for collection losses is believed by management to be probable in the Company’s accounts receivable. As of March 31, 2020 and 2019, no individual customer represented more than 10% of the Company’s accounts receivable. During the years ended March 31, 2020, 2019 and 2018, no individual customer represented more than 10% of the Company’s revenue. The Company's board of directors approved investment policy permits investments in fixed income securities denominated and payable in U.S. dollars, including U.S. government and agency securities, non-U.S. government securities, money market instruments, commercial paper, certificates of deposit, corporate bonds and asset-backed securities. The Company diversifies its investment portfolio by investing in multiple types of investment-grade securities across various industries and issuers, limiting the amount invested in individual securities and limiting the average maturity to two years or less and attempts to mitigate a risk of loss by using a third-party investment manager. As of March 31, 2020, the Company did not hold any investments. As of March 31, 2019, the Company’s investments consisted primarily of investment-grade fixed income corporate debt securities with maturities ranging from one to seven months, non-U.S. government securities with maturities ranging from three to eight months and U.S. treasury securities with maturities in approximately five months.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts The Company makes judgments as to its ability to collect outstanding receivables and provide allowances for the portion of receivables when a loss is reasonably expected to occur. The allowance for doubtful accounts is established to represent the best estimate of the net realizable value of the outstanding accounts receivable. The development of the allowance for doubtful accounts is based on a review of past due amounts, historical write-off and recovery experience, as well as aging trends affecting specific accounts and general operational factors affecting all amounts. In addition, factors are developed utilizing historical trends in bad debts, returns and allowances. The Company considers current economic trends when evaluating the adequacy of the allowance for doubtful accounts. If circumstances relating to specific customers change or unanticipated changes occur in the general business environment, the Company’s estimates of the recoverability of receivables could be further adjusted. For the years ended March 31, 2020, 2019 and 2018, bad debt expense was $0.3 million, $0.2 million and $0.2 million, respectively. The allowance for doubtful accounts as of March 31, 2020 and 2019 was not material.
Property and Equipment	Property and Equipment Property and equipment are stated at cost and are depreciated using the straight-line method over the estimated useful life of the assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the related asset. Property and equipment acquired under capital leases is amortized over the lease term or, in circumstances where ownership is transferred by the end of the lease or there is a bargain purchase option, over the useful life that would be assigned if the asset were owned. Upon retirement or sale, the cost of assets disposed of, and the related accumulated depreciation, are removed from the accounts, and any resulting gain or loss is included in the determination of net loss in the period of retirement or sale. The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life Computer equipment 3 to 5 Leasehold improvements Lesser of asset life or lease term Furniture and fixtures 5 Office equipment 3 Expenditures for maintenance and repairs are charged to expense as incurred, whereas major betterments are capitalized as additions to property and equipment.
Business Combinations	Business Combinations In accordance with ASC 805, Business Combinations The Company recognizes identifiable assets acquired and liabilities assumed at their acquisition date fair value. Goodwill as of the acquisition date is measured as the excess of consideration transferred over the net of the acquisition date fair value of the assets acquired and the liabilities assumed and represents the expected future economic benefits arising from other assets acquired that are not individually identified and separately recognized. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to accurately value assets acquired and liabilities assumed at the acquisition date, its estimates are inherently uncertain and subject to refinement. Assumptions may be incomplete or inaccurate, and unanticipated events or circumstances may occur, which may affect the accuracy or validity of such assumptions, estimates or actual results. As a result, during the measurement period, which may be up to one year from the acquisition date, the Company records adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill to the extent that it identifies adjustments to the preliminary purchase price allocation. Upon the conclusion of the measurement period or final determination of the values of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the consolidated statements of operations.
Goodwill and acquired intangible assets	Goodwill and acquired intangible assets Goodwill is not amortized, but is evaluated for impairment annually, or whenever events or changes in circumstances indicate that the carrying value may not be recoverable. The Company has determined that there is a single reporting unit for the purpose of conducting this goodwill impairment assessment. For purposes of assessing potential impairment, the Company estimates the fair value of the reporting unit, based on the Company’s market capitalization, and compares this amount to the carrying value of the reporting unit. If the Company determines that the carrying value of the reporting unit exceeds its fair value, an impairment charge would be required. The annual goodwill impairment test is performed as of January 1 st Intangible assets acquired in a business combination are recorded at their estimated fair values at the date of acquisition. The Company amortizes acquired definite-lived intangible assets over their estimated useful lives based on the pattern of consumption of the economic benefits or, if that pattern cannot be readily determined, on a straight-line basis.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews long-lived assets, including property and equipment, right-of-use assets, and definite-lived intangible assets, for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. During this review, the Company re-evaluates the significant assumptions used in determining the original cost and estimated lives of long-lived assets. Although the assumptions may vary from asset to asset, they generally include operating results, changes in the use of the asset, cash flows, and other indicators of value. Management then determines whether the remaining useful life continues to be appropriate, or whether there has been an impairment of long-lived assets based primarily upon whether expected future undiscounted cash flows are sufficient to support the recoverability of these assets. Recoverability of these assets is measured by comparison of the carrying amount of the asset to the future undiscounted cash flows the asset is expected to generate. If the asset is considered to be impaired, the amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired asset. For the years ended March 31, 2020 and 2019, the Company did not identify any indicators of impairment of its long-lived assets. For the year ended March 31, 2018, the Company recorded an i
Fair Value Measurements	Fair Value Measurements ASC 820, Fair Value Measurements and Disclosures ASC 820 identifies fair value as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants based on the highest and best use of the asset or liability. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. The Company uses valuation techniques to measure fair value that maximize the use of observable inputs and minimize the use of unobservable inputs. These inputs are prioritized as follows: • Level 1 inputs—Unadjusted observable quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. • Level 2 inputs—Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. • Level 3 inputs—Unobservable inputs for determining the fair values of assets or liabilities that reflect an entity’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The Company evaluates assets and liabilities subject to fair value measurements on a recurring and nonrecurring basis to determine the appropriate level to classify them for each reporting period. The Company measures eligible assets and liabilities at fair value, with changes in value recognized in earnings. Fair value treatment may be elected either upon initial recognition of an eligible asset or liability or, for an existing asset or liability, if an event triggers a new basis of accounting. The Company did not elect to remeasure any of its existing financial assets or liabilities and did not elect the fair value option for any financial assets and liabilities transacted in the years ended March 31, 2020, 2019 and 2018.
Internal-use Software Costs	Software Development Costs Costs incurred to develop software applications used in the Company’s SaaS platform consist of certain direct costs of materials and services incurred in developing or obtaining internal-use computer software, and payroll and payroll-related costs for employees who are directly associated with, and who devote time to, the project. These costs generally consist of internal labor during configuration, coding, and testing activities. Research and development costs incurred during the preliminary project stage or costs incurred for data conversion activities, training, maintenance and general and administrative or overhead costs are expensed as incurred. Once an application has reached the development stage, internal and external costs, if direct and incremental, are capitalized until the application is substantially complete and ready for its intended use. Qualified costs incurred during the operating stage of the Company’s software applications relating to upgrades and enhancements are capitalized to the extent it is probable that they will result in added functionality, while costs incurred for maintenance of, and minor upgrades and enhancements to, internal-use software are expensed as incurred. During the years ended March 31, 2020, 2019 and 2018, the Company believes the substantial majority of its development efforts were either in the preliminary project stage of development or in the operation stage (post-implementation), and accordingly, no costs have been capitalized during these periods. These costs are included in the accompanying consolidated statements of operations as research and development expense. Capitalized software and Cloud-computing Arrangements (CCA) The Company accounts for acquired internal-use software licenses and certain costs related to video content production related to its awareness training offering within the scope of ASC 350-40, Intangibles – Goodwill and Other – Internal-Use Software Additionally, the Company evaluates its accounting for fees paid in a CCA to determine whether the CCA includes a license to internal-use software. If the CCA includes a software license, the Company accounts for the software license as an intangible asset. Acquired software licenses are recognized and measured at cost, which includes the present value of the license obligation if the license is to be paid for over time. If the CCA does not include a software license, the Company accounts for the arrangement as a service contract (hosting arrangement) and hosting costs are generally expensed as incurred. Since the adoption of ASU 2018-15, Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-24): Customer’s Acco unting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract (ASU 2018-15), on July 1, 2018, the Company evaluates upfront costs including implementation, set-up or other costs (collectively, implementation costs) fo r hosting arrangements under the internal-use software framework. Costs related to preliminary project activities and post implementation activities are expensed as incurred, whereas costs incurred in the development stage are generally capitalized. Capita lized implementation costs are amortized on a straight-line basis over the expected term of the hosting arrangement, which includes consideration of the non-cancellable contractual term and reasonably certain renewals. As of March 31, 2020 and 2019, the ne t carrying value of capitalized implementation costs related to hosting arrangements that were incurred during the application development stage were $ 2.9 million and $ 1.6 million, respectively. These capitalized implementation costs will be amortized over the expected term of the arrangement and are amortized in the same line item in the consolidated statements of operations as the expense for fees for the associated hosti ng arrangement.
Foreign Currency Translation	Foreign Currency Translation The reporting currency of the Company is the U.S. dollar. The Company determines the functional currency for its non-U.S. subsidiaries by reviewing the currencies in which its respective operating activities occur. The functional currency of the Company’s non-U.S. subsidiaries is generally the local currency of each subsidiary. All assets and liabilities in the balance sheets of entities whose functional currency is a currency other than the U.S. dollar are translated into U.S. dollar equivalents at exchange rates as follows: (i) asset and liability accounts at period-end rates, (ii) income statement accounts at weighted-average exchange rates for the period, and (iii) shareholders’ equity accounts at historical exchange rates. Foreign exchange transaction gains and losses are included in foreign exchange (expense) income and other, net in the accompanying consolidated statements of operations. The effects of foreign currency translation adjustments are included as a component of accumulated other comprehensive loss in the accompanying consolidated balance sheets.
Net Loss Per Share	Net Loss Per Ordinary Share The Company calculates basic and diluted net loss per ordinary share by dividing net loss by the weighted-average number of ordinary shares outstanding during the period. The Company has excluded the following potentially dilutive shares, which include share options outstanding, unvested RSUs and estimated employee share purchase plan ESPP shares, from the weighted-average number of ordinary shares outstanding as their inclusion in the computation for all periods would be anti-dilutive due to net losses incurred (in thousands): Year Ended March 31, 2020 2019 2018 Share options outstanding 6,271 6,209 6,230 Unvested RSUs 1,277 550 33 ESPP Shares 82 85 76
Advertising and Promotion Costs	Advertising and Promotion Costs Expenses related to advertising and promotion of solutions is charged to sales and marketing expense as incurred. The Company incurred advertising expenses of $12.5 million, $12.5 million and $12.4 million during the years ended March 31, 2020, 2019 and 2018, respectively.
Income Taxes	Income Taxes The Company is subject to income tax in the United Kingdom, the United States and other international jurisdictions, and uses estimates in determining its provision for income taxes. The Company accounts for income taxes in accordance with ASC 740, Income Taxes The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not the tax position will be sustained on examination by the tax authorities, based on the technical merits of the position. The tax benefits recognized in the consolidated financial statements from such position are then measured based on the largest benefit that has a greater than 50% likelihood of being realized upon settlement. As of March 31, 2020 and 2019, the Company did not have any material uncertain tax positions that would impact the Company’s tax provision if recognized.
Share-Based Compensation	Share-Based Compensation The Company accounts for share-based compensation awards in accordance with the provisions of ASC 718, Compensation—Stock Compensation See Note 13 for further description of the Company’s share-based compensation plans and a summary of the share-based award activity for the year ended March 31, 2020. Share Options The Company estimates the fair value of employee share options on the date of grant using the Black-Scholes option-pricing model, which requires the use of highly subjective estimates and assumptions. The Company estimates the expected term of share options for service-based awards utilizing the “Simplified Method,” as it does not have sufficient historical share option exercise information on which to base its estimate. The Simplified Method is based on the average of the vesting tranches and the contractual life of each grant. The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected life of the share option. Since there was no public market for the Company’s ordinary shares prior to the Company’s initial public offering and as its ordinary shares have been publicly traded for a limited time, the Company determined the expected volatility for options granted based on an analysis of reported data for a peer group of companies that issue options with substantially similar terms. The expected volatility of options granted has been determined using an average of the historical volatility measures of this peer group of companies and the Company’s historical volatility. The Company uses an expected dividend rate of zero as it currently has no history or expectation of paying dividends on its ordinary shares. The fair value of the Company’s ordinary shares at the time of each share option grant is based on the closing market value of its ordinary shares on the grant date. The fair value of each share option grant was estimated using the Black-Scholes option-pricing model that used the following weighted-average assumptions: Year ended March 31, 2020 2019 2018 Expected term (in years) 6.1 6.1 6.1 Risk-free interest rate 2.1 % 2.7 % 2.2 % Expected volatility 42.6 % 41.5 % 39.8 % Expected dividend yield — % — % — % Estimated grant date fair value per ordinary share $ 46.29 $ 37.15 $ 26.52 The weighted-average per share fair value of share options granted to employees during the years ended March 31, 2020, 2019 and 2018 was $20.43, $16.48 and $11.12 per share, respectively. Employee Share Purchase Plan The Company estimates the fair value of its ESPP share options on the date of grant using the Black-Scholes option-pricing model, which requires the use of highly subjective estimates and assumptions. The Company estimates the expected term of ESPP share options based on the length of each offering period, which is six months. The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected life of the ESPP share option. Expected volatility is based on an average of the historical volatility measures of the peer group of companies noted above and the Company’s historical volatility. The Company uses an expected dividend rate of zero as it currently has no history or expectation of paying dividends on its ordinary shares. The grant date fair value per ordinary share is based on the closing market value of its ordinary shares on the first day of each ESPP offering period. The first authorized offering period under the ESPP commenced on July 1, 2017. The fair value of each ESPP option grant was estimated using the Black-Scholes option-pricing model that used the following weighted-average assumptions: Year ended March 31, 2020 2019 2018 Expected term (in years) 0.5 0.5 0.5 Risk-free interest rate 1.8 % 2.3 % 1.4 % Expected volatility 37.4 % 39.1 % 29.9 % Expected dividend yield — % — % — % Grant date fair value per ordinary share $ 45.41 $ 36.69 $ 27.15 The weighted-average per share fair value of ESPP share options granted to employees during the years ended March 31, 2020, 2019 and 2018, was $11.73, $9.58 and $6.41, respectively. RSUs For RSUs issued under the Company’s share-based compensation plans, the fair value of each grant is calculated based on the closing market value of its ordinary shares on the date of grant.
Leases	Leases In accordance with ASU 2016-02, effective April 1, 2019, the Company classifies leases at the lease commencement date. At the commencement date, the Company will recognize a right-of-use asset (ROUA) and a lease liability on the balance sheet for all leases with the exception of facilities leases with a lease term of 12 months or less. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company has elected to account for lease and non-lease components as a single lease component. Lease liabilities and their corresponding ROUAs are recorded based on the present value of lease payments over the expected lease term. The implicit rate within the Company’s leases are generally not determinable and therefore the Company uses the incremental borrowing rate at the lease commencement date to determine the present value of lease payments. The Company determines its incremental borrowing rate for each lease based on the rate of interest that the Company would have to pay to borrow an amount equal to the lease payments on a collateralized basis over a similar term. Certain of the Company’s leases include options to extend or terminate the lease. An option to extend the lease is considered in connection with determining the ROUA and lease liability when it is reasonably certain the Company will exercise that option. An option to terminate is considered unless it is reasonably certain the Company will not exercise the option. Refer to Note 9 for further information.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions, other events, and circumstances from non-owner sources. Comprehensive loss consists of net loss and other comprehensive (loss) income, which includes certain changes in equity that are excluded from net loss. As of March 31, 2020 and 2019, accumulated other comprehensive loss is presented separately on the consolidated balance sheets and consists of cumulative foreign currency translation adjustments and unrealized gains and losses on investments.
Recently Issued and Adopted Accounting Pronouncements	Recently Issued and Adopted Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Recently Adopted Accounting Pronouncements On April 1, 2019, the Company adopted ASU 2016-02, which requires a lessee to recognize most leases on the balance sheet but recognize expenses on the income statement in a manner similar to historical practice. The update states that a lessee will recognize a lease liability for the obligation to make lease payments and a right-of-use asset for the right to use the underlying assets for the lease term. The Company adopted ASU 2016-02 utilizing the modified retrospective transition method in the first quarter of fiscal 2020 and did not restate comparative periods. The Company has elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed it to carry forward the historical lease classification. Refer to Note 9 for further information on the impact of the adoption of ASU 2016-02 on the Company’s consolidated financial statements. On April 1, 2019, the Company adopted ASU 2018-07, Compensation—Stock Comp ensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (ASU 2018-07). ASU 2018-07 simplifies the accounting for share-based payments to non-employees by aligning it with the accounting for share-based payments to employees, with c ertain exceptions. The adoption of this standard had no impact on the Company’s consolidated financial statements. Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Schedule of Cash, Cash Equivalents And Investments	The following is a summary of cash, cash equivalents and investments as of March 31, 2020 and March 31, 2019: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value March 31, 2020: Cash and cash equivalents due in 90 days or less $ 173,958 $ — $ — $ 173,958 Total cash, cash equivalents and investments $ 173,958 $ — $ — $ 173,958 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value March 31, 2019: Cash and cash equivalents due in 90 days or less $ 137,576 $ — $ — $ 137,576 Investments: U.S. treasury securities due in one year or less 1,993 1 — 1,994 Non-U.S. government securities due in one year or less 7,969 12 — 7,981 Corporate securities due in one year or less 25,951 24 (9 ) 25,966 Total investments 35,913 37 (9 ) 35,941 Total cash, cash equivalents and investments $ 173,489 $ 37 $ (9 ) $ 173,517
Estimated Useful Lives of Property and Equipment	The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life Computer equipment 3 to 5 Leasehold improvements Lesser of asset life or lease term Furniture and fixtures 5 Office equipment 3
Dilutive Ordinary Shares Excluded from Calculation of Diluted Weighted Average Shares Outstanding	Year Ended March 31, 2020 2019 2018 Share options outstanding 6,271 6,209 6,230 Unvested RSUs 1,277 550 33 ESPP Shares 82 85 76
Summary of Weighted Average Assumption Utilized to Determine Fair Value of Option	The fair value of each share option grant was estimated using the Black-Scholes option-pricing model that used the following weighted-average assumptions: Year ended March 31, 2020 2019 2018 Expected term (in years) 6.1 6.1 6.1 Risk-free interest rate 2.1 % 2.7 % 2.2 % Expected volatility 42.6 % 41.5 % 39.8 % Expected dividend yield — % — % — % Estimated grant date fair value per ordinary share $ 46.29 $ 37.15 $ 26.52
Summary of Assumptions Used in Black-Scholes Option Pricing Model to Estimate Fair Value of Shares Under the ESPP	The fair value of each ESPP option grant was estimated using the Black-Scholes option-pricing model that used the following weighted-average assumptions: Year ended March 31, 2020 2019 2018 Expected term (in years) 0.5 0.5 0.5 Risk-free interest rate 1.8 % 2.3 % 1.4 % Expected volatility 37.4 % 39.1 % 29.9 % Expected dividend yield — % — % — % Grant date fair value per ordinary share $ 45.41 $ 36.69 $ 27.15

Balance Sheet Components (Table

Balance Sheet Components (Tables)	12 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consist of the following: As of March 31, 2020 2019 Prepaid expenses $ 11,498 $ 11,259 Research and development investment tax credits 2,665 3,862 Lease incentive due from landlord — 8,900 Other current assets 1,982 1,850 Total prepaid expenses and other current assets $ 16,145 $ 25,871
Schedule of Property and Equipment, Net	Property and equipment, net, consists of the following: As of March 31, 2020 2019 Building and building improvements (1) $ — $ 47,001 Computer equipment (2) 131,920 112,277 Leasehold improvements 34,031 8,166 Furniture and fixtures 5,793 4,590 Office equipment 2,084 1,345 173,828 173,379 Less: Accumulated depreciation and amortization (1) (2) (88,650 ) (79,177 ) Property and equipment, net $ 85,178 $ 94,202 (1 ) As of March 31, 2019 U.S. build-to-suit facility $ 47,001 Less: Accumulated depreciation (5,164 ) $ 41,837 As of March 31, 2019, the U.S. build-to-suit facility includes company-funded building improvements of $5.2 million . (2) Includes property and equipment acquired under finance leases: As of March 31, 2020 2019 Computer equipment $ 4,714 $ 4,754 Less: Accumulated amortization (3,407 ) (2,228 ) $ 1,307 $ 2,526
Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consists of the following: As of March 31, 2020 2019 Accrued payroll and related benefits $ 23,465 $ 21,198 Accrued taxes payable 5,809 5,305 Construction financing lease obligation — 2,670 Restructuring liability — 49 Other accrued expenses 12,333 15,087 Total accrued expenses and other current liabilities $ 41,607 $ 44,309
Other Non-current Liabilities	Other non-current liabilities consist of the following: As of March 31, 2020 2019 Deferred rent (3) $ — $ 10,218 Other non-current liabilities 4,386 5,363 Total other non-current liabilities $ 4,386 $ 15,581 (3 ) Upon the adoption of ASU 2016-02 on April 1, 2019, the Company recognized a ROUA and a lease liability on the balance sheet and therefore recognizes lease expense for operating leases on a straight-line basis over the lease term. See Note 9 for further details.

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Summary of Final Purchase Price Allocation	The following table summarizes the final purchase price allocation: Purchase consideration: Total cash paid, net of acquired cash $ 85,258 Cash and cash equivalents acquired 10,410 Fair value of previously held asset 828 Total purchase price consideration $ 96,496 Fair value of assets acquired and liabilities assumed: Cash and cash equivalents $ 10,410 Prepaid expenses and other current assets 76 Intangible assets 16,964 Goodwill 74,469 Total assets acquired 101,919 Accounts payable (18 ) Accrued expenses and other current liabilities (2,345 ) Deferred revenue (663 ) Other non-current liabilities (2,397 ) Total fair value of assets acquired and liabilities assumed $ 96,496
Summary of Estimated Fair Values and Useful Lives of Identifiable Intangible	The following table presents the estimated fair values and useful lives of the identifiable intangible assets acquired: Amount Estimated Useful Life (in years) Developed technology $ 16,689 10 Customer relationships 235 7 Trade names 40 1 Total identifiable intangible assets $ 16,964
Summary of Pro Forma Financial Information (unaudited)	Accordingly, these unaudited pro forma results are presented for informational purposes only and are not necessarily indicative of the results of operations that would have been achieved had the acquisition occurred as of April 1, 2017, nor are they intended to represent or be indicative of future results of operations (in thousands, except per share amounts): Year ended March 31, 2019 Revenue $ 340,824 Net loss (7,729 ) Basic and diluted net loss per share $ (0.13 ) Weighted average number of ordinary shares outstanding Basic and diluted 59,960

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Mar. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Goodwill Balance	The following table reflects goodwill activity in each of the periods presented: Year ended March 31, 2020 2019 Beginning balance $ 107,575 $ 5,631 Goodwill acquired 42,927 101,381 Effect of foreign exchange rates 23 563 Ending balance $ 150,525 $ 107,575
Schedule of Purchased Intangible Assets	Purchased intangible assets consist of the following: Weighted- Average March 31, 2020 Remaining Gross Net Useful Life Carrying Accumulated Carrying (in years) Value Amortization Value Developed technology 8 $ 33,269 $ (4,547 ) $ 28,722 Customer relationships 5 771 (159 ) 612 Trade names N/A 41 (41 ) — Capitalized software and other (1) (2) 3 16,849 (7,789 ) 9,060 $ 50,930 $ (12,536 ) $ 38,394 Weighted- Average March 31, 2019 Remaining Gross Net Useful Life Carrying Accumulated Carrying (in years) Value Amortization Value Developed technology 9 $ 23,577 $ (1,707 ) $ 21,870 Customer relationships 6 455 (73 ) 382 Trade names 1 56 (34 ) 22 Capitalized software (1) 3 12,431 (4,082 ) 8,349 $ 36,519 $ (5,896 ) $ 30,623 (1) As of March 31, 2020 and 2019, the net carrying value of capitalized software and other includes $1.4 million and $0.5 million, respectively of costs capitalized related to video production costs. See Note 2 for further information. (2) As of March 31, 2020, the net carrying value of capitalized software and other includes $0.2 million of costs capitalized related to IP addresses.
Schedule of Future Estimated Amortization Expense of Acquired Intangible Assets	Future estimated amortization expense of intangible assets as of March 31, 2020 is as follows: Purchased Intangible Capitalized Assets Software 2021 $ 3,827 $ 3,998 2022 3,827 2,701 2023 3,827 1,676 2024 3,772 395 2025 3,701 236 Thereafter 10,380 54 Total $ 29,334 $ 9,060

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Summary of Financial Assets Measured and Recorded at Fair Value on Recurring Basis	The following table summarizes financial assets measured and recorded at fair value on a recurring basis in the accompanying consolidated balance sheets as of March 31, 2020 and 2019, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value: March 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1 Inputs) Significant Other Observable Inputs (Level 2 Inputs) Total Assets: Money market funds $ 17,495 $ — $ 17,495 March 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1 Inputs) Significant Other Observable Inputs (Level 2 Inputs) Total Assets: Money market funds $ 8,348 $ — $ 8,348 U.S. treasury securities — 1,994 1,994 Non-U.S. government securities — 7,981 7,981 Corporate securities — 25,966 25,966 Total assets $ 8,348 $ 35,941 $ 44,289

Leases (Tables)

Leases (Tables)	12 Months Ended
	Mar. 31, 2020
Schedule of Components of Lease Expense	The components of lease expense were as follows: Year ended March 31, 2020 Short-term lease cost $ 308 Variable lease cost 4,144 Operating lease cost 37,906 Finance lease cost: Amortization of lease assets 1,179 Interest on lease liabilities 93 Total finance lease cost $ 1,272
Schedule of Supplemental Cash Flow Information Related to Leases	Supplemental cash flow information related to leases was as follows: Year ended March 31, 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash outflows from operating leases $ 32,816 Operating cash outflows from finance leases $ 74 Financing cash outflows from finance leases $ 844
Schedule of Weighted-average Remaining Lease Term and Discount Rate	Weighted-average remaining lease term and discount rate: As of March 31, 2020 Weighted-average remaining lease term (in years) Operating leases 6.46 Finance leases 1.31 Weighted-average discount rate Operating leases 4.74 % Finance leases 4.83 %
Schedule of Maturities of Lease Liabilities	Maturities of lease liabilities as of March 31, 2020 were as follows: Year Ending March 31, Operating Leases Finance Leases 2021 $ 36,231 $ 1,102 2022 27,653 326 2023 21,291 — 2024 14,741 — 2025 14,254 — Thereafter 43,516 — Total lease payments 157,686 1,428 Less: imputed interest (21,986 ) (47 ) Total lease liabilities $ 135,700 $ 1,381
Future Minimum Payments for Capital Leases, Facility Operating Leases and Data Center Operating Leases	As previously disclosed in the Company’s Annual Report on Form 10-K for the fiscal year ended March 31, 2019 and under the previous lease accounting standard, future minimum payments for capital leases, facility operating leases (including Lexington MA – U.S. build-to-suit lease) and data center operating leases as of March 31, 2019 were as follows: Year Ending March 31, Capital Leases Facility Leases Data Centers 2020 $ 918 $ 10,649 $ 21,216 2021 1,102 15,186 17,427 2022 326 14,111 13,010 2023 — 13,825 2,774 2024 — 13,686 356 Thereafter — 59,502 — Total minimum lease payments 2,346 $ 126,959 $ 54,783 Less: Amount representing interest (121 ) Present value of capital lease obligations 2,225 Less: Current portion (844 ) Long-term portion of capital lease obligations $ 1,381
ASU 2016-02 [Member]
Schedule of Impact of Adoption of ASC 842	The impact of the adoption of ASC 842 is as follows: Balance as of March 31, 2019 Adjustments Due to Adoption of ASC 842 Balance as of April 1, 2019 Assets Prepaid expenses and other current assets $ 25,871 $ (939 ) $ 24,932 Property and equipment, net 94,202 (30,963 ) 63,239 Operating lease right-of-use assets — 141,280 141,280 Other assets 5,156 (2,566 ) 2,590 Liabilities Accrued expenses and other current liabilities 44,309 (3,248 ) 41,061 Current portion of operating lease liabilities — 27,611 27,611 Construction financing lease obligations 36,650 (36,650 ) - Operating lease liabilities — 127,119 127,119 Other non-current liabilities 15,581 (10,192 ) 5,389 Shareholders' equity Accumulated deficit (83,632 ) 2,172 (81,460 )

Debt (Tables)

Debt (Tables)	12 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Schedule of Future Minimum Principal Payment Obligations	Future minimum principal payment obligations under the Term Loan are as follows: Year Ending March 31, Debt 2021 6,875 2022 9,375 2023 10,000 2024 67,500 Total minimum debt payments 93,750 Less: Debt issuance costs (919 ) Less: Current portion of long-term debt (6,573 ) Long-term debt $ 86,258

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Summary of Ordinary Share Reserved for Future Issuance under 2015 Plan, Historical Plans and ESPP	The following ordinary shares were reserved for future issuance under the 2015 Plan, Historical Plans and ESPP (as defined below in Note 13): As of March 31, 2020 Options outstanding under share option plans 6,271,111 Unvested RSUs 1,276,840 Options and awards available for future grant under the 2015 Plan 9,992,607 Shares reserved for issuance under ESPP 748,903 Total authorized ordinary shares reserved for future issuance 18,289,461

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Share-Based Compensation Expense Recognized in Statements of Operations	Share-based compensation expense recognized under the 2015 Plan, Historical Plans and ESPP in the accompanying consolidated statements of operations was as follows: Year ended March 31, 2020 2019 2018 Cost of revenue $ 3,445 $ 1,684 $ 1,053 Research and development 10,900 6,199 2,555 Sales and marketing 13,141 7,856 4,477 General and administrative 12,058 10,215 3,649 Total share-based compensation expense $ 39,544 $ 25,954 $ 11,734
Schedule of Share-Based Compensation, Stock Options, Activity	Share option activity under the 2015 Plan and Historical Plans for the year ended March 31, 2020 was as follows: Number of Awards Weighted Exercise Price (1) Weighted Remaining Contractual Term (in years) Aggregate Intrinsic Outstanding as of March 31, 2019 6,208,964 $ 23.47 7.58 $ 148,313 Options granted 2,016,318 $ 46.29 Options exercised (1,359,903 ) $ 14.81 Options forfeited and cancelled (594,268 ) $ 35.39 Outstanding as of March 31, 2020 6,271,111 $ 31.61 7.55 $ 47,621 Exercisable as of March 31, 2020 2,602,224 $ 20.43 6.24 $ 40,224 (1) Certain of the Company’s option grants have an exercise price denominated in British pounds. The weighted-average exercise price at the end of each reporting period was translated into U.S. dollars using the exchange rate at the end of the period. The weighted-average exercise price for the options granted, exercised, forfeited and cancelled was translated into U.S. dollars using the exchange rate at the applicable date of grant, exercise, forfeiture or cancellation, as appropriate.
Schedule of Share-Based Compensation, RSUs, Activity	RSU activity under the 2015 Plan for the year ended March 31, 2020 was as follows: Number of Shares Weighted Average Grant Date Fair Value Intrinsic Value (in thousands) (1) Unvested RSUs as of March 31, 2019 549,853 $ 37.15 $ 26,036 RSUs granted 1,015,290 $ 46.17 RSUs vested (161,450 ) $ 37.04 RSUs forfeited (126,853 ) $ 44.08 Unvested RSUs as of March 31, 2020 1,276,840 $ 43.64 $ 45,072 (1) As of March 31, 2020 and 2019, the intrinsic value of unvested shares was calculated based on the closing price of the Company’s ordinary shares on the NASDAQ Global Select Market on March 31, 2020 and 2019, respectively, multiplied by the number of unvested RSUs.

Segment and Geographic Inform_2

Segment and Geographic Information (Tables)	12 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Summary of Revenue by Geographic Area	The Company allocates, for the purpose of geographic data reporting, its revenue based upon the location of the contracting subsidiary. Total revenue by geographic area was as follows: Year ended March 31, 2020 2019 2018 United States $ 219,423 $ 169,286 $ 128,503 United Kingdom 123,620 103,900 81,720 South Africa 51,549 46,275 39,425 Other 32,371 20,916 12,249 Total revenue $ 426,963 $ 340,377 $ 261,897
Summary of Property and Equipment, Net by Geographic Location	Property and equipment, net by geographic location consisted of the following: As of March 31, 2020 2019 United States (1) $ 39,193 $ 62,455 United Kingdom 29,644 17,402 South Africa 7,093 6,170 Other 9,248 8,175 Total $ 85,178 $ 94,202 (1) Includes construction costs capitalized under financing lease obligations related to the Company’s U.S. build-to-suit facility of $41.8 million as of March 31, 2019.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Summary of Income (Loss) Before Income Taxes	Income (loss) before income taxes consists of the following: Year ended March 31, 2020 2019 2018 United Kingdom $ (20,528 ) $ (4,626 ) $ (15,939 ) Foreign 20,687 (374 ) 6,258 Income (loss) before income taxes $ 159 $ (5,000 ) $ (9,681 )
Schedule of Provision for Income Taxes	The provision for income taxes in the accompanying consolidated financial statements is comprised of the following: As of March 31, 2020 2019 2018 Current tax expense: Domestic $ — $ — $ — Foreign 2,939 3,493 2,597 Total current tax expense 2,939 3,493 2,597 Deferred tax expense: Domestic — (578 ) — Foreign (580 ) (914 ) 108 Total deferred tax (benefit) expense (580 ) (1,492 ) 108 Total provision for income taxes $ 2,359 $ 2,001 $ 2,705
Schedule of Reconciliation of Statutory Tax Rate to Effective Tax Rate	The reconciliation of the United Kingdom statutory tax rate to the Company’s effective tax rate included in the accompanying consolidated statements of operations is as follows: Year ended March 31, 2020 2019 2018 Tax at statutory rate 19.0 % 19.0 % 19.0 % U.S. state taxes, net of federal 558.0 31.1 14.1 Foreign rate differential 291.5 26.3 36.8 Meals and entertainment 432.6 (11.4 ) (3.1 ) Branch (income) loss (69.9 ) (0.6 ) 0.4 Share-based compensation (2,341.9 ) 172.3 105.3 Tax credits (375.5 ) 7.7 8.1 Unremitted earnings 101.3 (3.8 ) (1.2 ) Change in valuation allowance (1,456.8 ) (249.9 ) (110.7 ) Deferred tax true-ups 116.2 (3.5 ) 8.4 Tax reserves 3,147.4 (4.9 ) (21.5 ) Provision to return 37.6 (0.1 ) 0.4 Withholding taxes 323.5 (2.6 ) (3.5 ) Non-deductible expenses 197.7 (5.2 ) (2.4 ) Deferred tax rate change 473.1 (6.3 ) (77.8 ) Acquisition-related costs 91.7 (7.6 ) — Foreign exchange (59.5 ) — — Other (2.4 ) (0.5 ) (0.2 ) Effective Tax Rate 1,483.6 % (40.0 )% (27.9 )%
Components of Deferred Tax Assets and (Liabilities)	Deferred tax assets and liabilities reflect the net tax effects of net operating loss carryovers and the temporary differences between the assets and liabilities carrying value for financial reporting and the amounts used for income tax purposes. T As of March 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 30,879 $ 35,120 Share-based compensation 9,501 5,687 Deferred revenue 2,315 1,761 Fixed assets 4,718 4,187 Lease liability 30,890 11,748 Accrued compensation 1,786 1,211 Deferred rent — 320 Income tax credits 2,311 1,833 Other 2,042 1,648 Gross deferred tax assets 84,442 63,515 Deferred tax liabilities: Fixed assets (7,414 ) (13,855 ) Unremitted earnings (362 ) (320 ) Intangible assets (6,453 ) (4,818 ) Capitalized commissions (9,751 ) (7,606 ) Right-of-use asset (26,498 ) — Other (2,145 ) (606 ) Gross deferred tax liabilities (52,623 ) (27,205 ) Valuation allowance (34,224 ) (38,318 ) Deferred tax liabilities, net $ (2,405 ) $ (2,008 )
Summary of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: Year ended March 31, 2020 2019 Beginning balance $ 6,016 $ 6,164 Additions based on tax positions related to current year 535 164 Additions for tax positions of prior years 4,235 231 Reductions due to change in foreign exchange rate (431 ) (301 ) Expiration of statutes of limitation — (165 ) Reductions due to settlements with tax authorities — (77 ) Ending balance $ 10,355 $ 6,016

Quarterly Results of Operatio_2

Quarterly Results of Operations Data (unaudited) (Tables)	12 Months Ended
	Mar. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Summary of Quarterly Results of Operations Data	The following tables set forth our unaudited quarterly consolidated statements of operations for each of the eight quarters in the period ended March 31, 2020. The Company has prepared the quarterly consolidated statements of operations data on a basis consistent with the audited consolidated financial statements included elsewhere in this Annual Report on Form 10-K. In the opinion of management, the financial information reflects all adjustments, consisting only of normal recurring adjustments, which management considers necessary for a fair presentation of this data. This information should be read in conjunction with the audited consolidated financial statements and related notes included elsewhere in this Annual Report on Form 10-K. The results of historical periods are not necessarily indicative of the results to be expected for any future period. Quarter ended Mar 31, Dec 31, Sep 30, Jun 30, Mar 31, Dec 31, Sep 30, Jun 30, 2020 2019 2019 2019 2019 2018 2018 2018 (in thousands, except per share amounts) Revenue $ 114,217 $ 110,158 $ 103,357 $ 99,231 $ 92,193 $ 87,611 $ 82,169 $ 78,404 Gross profit 84,891 81,703 77,223 73,764 67,491 64,353 60,231 57,428 Income (loss) from operations 5,125 1,629 (18 ) (4,438 ) 207 1,572 (909 ) (2,089 ) Net income (loss) 2,525 206 (921 ) (4,010 ) (1,930 ) 458 (2,058 ) (3,471 ) Net income (loss) per ordinary share: Basic $ 0.04 $ 0.00 $ (0.01 ) $ (0.07 ) $ (0.03 ) $ 0.01 $ (0.03 ) $ (0.06 ) Diluted $ 0.04 $ 0.00 $ (0.01 ) $ (0.07 ) $ (0.03 ) $ 0.01 $ (0.03 ) $ (0.06 ) Weighted-average number of ordinary shares outstanding: Basic 62,636 62,189 61,829 61,444 60,733 60,141 59,800 59,175 Diluted 64,382 63,996 61,829 61,444 60,733 62,537 59,800 59,175

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2020USD ($)Customer$ / shares	Mar. 31, 2019USD ($)Customer$ / shares	Mar. 31, 2018USD ($)Customer$ / shares
Summary Of Significant Accounting Policies [Line Items]
Proceeds from issuance of ordinary shares	$ 2,476,000	$ 298,000	$ 89,000
Realized gains or losses on investments	0	0	0
Investments hold in unrealized loss position for less than twelve months	$ 0	$ 10,000,000	$ 10,000,000
Maximum percentage of revenue contribution from professional services and other revenue	5.00%	5.00%	5.00%
Upfront ingestion fee to be recognized over estimated customer benefit period	6 years
Number of customers representing more than 10% of accounts receivable | Customer	0	0
Number of customers representing more than 10% of revenue | Customer	0	0	0
Bad debt expenses	$ 300,000	$ 200,000	$ 200,000
Annual goodwill impairment test date	January 1st of each year
Impairment of long-lived assets	$ 0	0	1,712,000
Capitalized costs	0	0	0
Implementation costs capitalized	2,900,000	1,600,000
Advertising expenses incurred	12,500,000	12,500,000	$ 12,400,000
Uncertain tax positions impact to net tax provision	$ 0	$ 0
Weighted-average per share fair value of share options granted to employees | $ / shares	$ 20.43	$ 16.48	$ 11.12
2015 Employee Share Purchase Plan [Member]
Summary Of Significant Accounting Policies [Line Items]
Expected dividend rate	0.00%
Weighted-average per share fair value of share options granted to employees | $ / shares	$ 11.73	$ 9.58	$ 6.41
Share Options [Member]
Summary Of Significant Accounting Policies [Line Items]
Expected dividend rate	0.00%
Capitalized Software Video Production Costs [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated Useful Life (in years)	5 years
U.S. Treasury Securities [Member]
Summary Of Significant Accounting Policies [Line Items]
Investment maturity period	5 months
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Investment maturity period	2 years
Maximum [Member] | Corporate Securities [Member]
Summary Of Significant Accounting Policies [Line Items]
Investment maturity period	7 months
Maximum [Member] | Non-U.S. Government Securities [Member]
Summary Of Significant Accounting Policies [Line Items]
Investment maturity period	8 months
Minimum [Member] | Corporate Securities [Member]
Summary Of Significant Accounting Policies [Line Items]
Investment maturity period	1 month
Minimum [Member] | Non-U.S. Government Securities [Member]
Summary Of Significant Accounting Policies [Line Items]
Investment maturity period	3 months
ASU 2014-09 [Member]
Summary Of Significant Accounting Policies [Line Items]
Amortization period of deferred contract costs	6 years
Payment of commissions related to contract renewals	$ 0
Adjustment [Member]
Summary Of Significant Accounting Policies [Line Items]
Proceeds from issuance of ordinary shares		$ 300,000	$ 100,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Cash, Cash Equivalents and Investments (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents due in 90 days or less, Cost	$ 173,958	$ 137,576
Cash and cash equivalents due in 90 days or less, Estimated fair value	173,958	137,576
Investments, Cost		35,913
Investments, Gross unrealized gains		37
Investments, Gross unrealized losses		(9)
Investments, Estimated fair value		35,941
Total cash, cash equivalents and investments, Cost	173,958	173,489
Total cash, cash equivalents and investments, Gross unrealized gains		37
Total cash, cash equivalents and investments, Gross unrealized Losses		(9)
Total cash, cash equivalents and investments, Estimated fair value	173,958	173,517
Cash and cash equivalents	$ 173,958	137,576
U.S. Treasury Securities Due in One Year or Less [Member]
Cash And Cash Equivalents [Line Items]
Investments, Cost		1,993
Investments, Gross unrealized gains		1
Investments, Estimated fair value		1,994
Non-U.S. Government Securities Due in One Year or Less [Member]
Cash And Cash Equivalents [Line Items]
Investments, Cost		7,969
Investments, Gross unrealized gains		12
Investments, Estimated fair value		7,981
Corporate Securities Due in One Year or Less [Member]
Cash And Cash Equivalents [Line Items]
Investments, Cost		25,951
Investments, Gross unrealized gains		24
Investments, Gross unrealized losses		(9)
Investments, Estimated fair value		$ 25,966

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Estimated Useful Lives of Property and Equipment (Detail)	12 Months Ended
	Mar. 31, 2020
Computer Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Computer Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	Lesser of asset life or lease term
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Dilutive Ordinary Shares Excluded from Calculation of Diluted Weighted-Average Shares Outstanding (Detail) - shares shares in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Share Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive ordinary share equivalents excluded from calculation of diluted weighted-average shares outstanding	6,271	6,209	6,230
Unvested Restricted Share Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive ordinary share equivalents excluded from calculation of diluted weighted-average shares outstanding	1,277	550	33
ESPP Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive ordinary share equivalents excluded from calculation of diluted weighted-average shares outstanding	82	85	76

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Summary of Weighted-Average Assumption Utilized to Determine Fair Value of Option (Detail) - Share Options [Member] - $ / shares	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days	6 years 1 month 6 days
Risk-free interest rate	2.10%	2.70%	2.20%
Expected volatility	42.60%	41.50%	39.80%
Expected dividend yield	0.00%
Estimated grant date fair value per ordinary share	$ 46.29	$ 37.15	$ 26.52

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Summary of Assumptions Used in Black-Scholes Option Pricing Model to Estimate Fair Value of Shares Under the ESPP (Detail) - 2015 Employee Share Purchase Plan [Member] - $ / shares	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 months	6 months	6 months
Risk-free interest rate	1.80%	2.30%	1.40%
Expected volatility	37.40%	39.10%	29.90%
Expected dividend yield	0.00%
Estimated grant date fair value per ordinary share	$ 45.41	$ 36.69	$ 27.15

Revenue and Deferred Revenue -

Revenue and Deferred Revenue - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenue From Contract With Customer [Abstract]
Revenue recognized included in deferred revenue	$ 158.8	$ 118.7
Contracted revenue not yet recognized	$ 97.2	$ 86
Contracted revenue not yet recognized, expected timing of satisfaction, explanation	The Company expects 54% of contracted and not recognized revenue to be recognized over the next year, 44% in years two and three, with the remaining balance recognized thereafter.

Revenue and Deferred Revenue _2

Revenue and Deferred Revenue - Additional Information (Detail 1)	Mar. 31, 2020
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-04-01
Disaggregation Of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	54.00%
Revenue, remaining performance obligation, expected timing of satisfaction, period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-04-01
Disaggregation Of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	44.00%
Revenue, remaining performance obligation, expected timing of satisfaction, period	24 months

Balance Sheet Components - Prep

Balance Sheet Components - Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Prepaid Expense And Other Assets Current [Abstract]
Prepaid expenses	$ 11,498	$ 11,259
Research and development investment tax credits	2,665	3,862
Lease incentive due from landlord		8,900
Other current assets	1,982	1,850
Total prepaid expenses and other current assets	$ 16,145	$ 25,871

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 173,828	$ 173,379
Less: Accumulated depreciation and amortization	(88,650)	(79,177)
Property and equipment, net	85,178	94,202
Buildings and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		47,001
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	131,920	112,277
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	34,031	8,166
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,793	4,590
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,084	$ 1,345

Balance Sheet Components - Sc_2

Balance Sheet Components - Schedule of Property and Equipment, Net (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 173,828	$ 173,379
Less: Accumulated depreciation and amortization	(88,650)	(79,177)
Property and equipment, net	85,178	94,202
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,714	4,754
Less: Accumulated depreciation and amortization	(3,407)	(2,228)
Property and equipment, net	1,307	2,526
United States [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 39,193	62,455
United States [Member] | Construction Costs Capitalized Related to Build-to-suit Facility [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		47,001
Less: Accumulated depreciation and amortization		(5,164)
Property and equipment, net		$ 41,837

Balance Sheet Components - Addi

Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 173,828	$ 173,379
Depreciation and amortization	25,200	25,200	$ 17,500
Depreciation and amortization related to property and equipment acquired under capital leases	$ 1,179	1,200	$ 900
Building Improvements [Member] | United States [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 5,200

Balance Sheet Components - Accr

Balance Sheet Components - Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Payables And Accruals [Abstract]
Accrued payroll and related benefits	$ 23,465	$ 21,198
Accrued taxes payable	5,809	5,305
Construction financing lease obligation		2,670
Restructuring liability		49
Other accrued expenses	12,333	15,087
Total accrued expenses and other current liabilities	$ 41,607	$ 44,309

Balance Sheet Components - Othe

Balance Sheet Components - Other Non-current Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Other Liabilities Disclosure [Abstract]
Deferred rent		$ 10,218
Other non-current liabilities	$ 4,386	5,363
Total other non-current liabilities	$ 4,386	$ 15,581

Restructuring - Additional Info

Restructuring - Additional Information (Detail) - Watertown, MA Corporate Office [Member] - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2018	Mar. 31, 2018
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 0.2	$ 0.8
Fair value of the restructuring liability		1.1
Deferred rent liabilities		$ 0.3

Acquisitions - Additional Infor

Acquisitions - Additional Information (Detail) - USD ($) $ in Thousands	Jan. 03, 2020	Nov. 13, 2019	Jan. 25, 2019	Jul. 31, 2018	Jul. 09, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Business Acquisition [Line Items]
Net of cash acquired						$ 45,280	$ 115,673	$ 1,381
Goodwill						$ 150,525	$ 107,575	$ 5,631
Developed Technology [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)						8 years	9 years
Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)						5 years	6 years
Segasec Labs Ltd. [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount	$ 6,800
Goodwill	24,000
Segasec Labs Ltd. [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount	$ 6,700
Estimated Useful Life (in years)	8 years 3 months 18 days
Segasec Labs Ltd. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount	$ 100
Estimated Useful Life (in years)	6 years 3 months 18 days
Segasec Labs Ltd. [Member] | Israel [Member]
Business Acquisition [Line Items]
Business acquisition, effective date of acquisition	Jan. 3, 2020
Ownership interest before acquisition	15.40%
Fair value of previously held asset	$ 3,000
Cash payment	24,200
Net of cash acquired	$ 4,300
DMARC Analyzer B.V. [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount		$ 3,400
Goodwill		18,900
DMARC Analyzer B.V. [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount		$ 3,200
Estimated Useful Life (in years)		7 years 6 months
DMARC Analyzer B.V. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount		$ 200
Estimated Useful Life (in years)		5 years 6 months
DMARC Analyzer B.V. [Member] | Netherlands [Member]
Business Acquisition [Line Items]
Business acquisition, effective date of acquisition		Nov. 13, 2019
Cash payment		$ 21,100
Net of cash acquired		$ 400
Solebit Labs Ltd. [Member]
Business Acquisition [Line Items]
Fair value of previously held asset				$ 828
Net of cash acquired				85,258
Estimated fair values of identifiable intangible assets, amount				16,964
Goodwill				74,469
Purchase price				96,496
Solebit Labs Ltd. [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount				$ 16,689
Estimated Useful Life (in years)				10 years
Solebit Labs Ltd. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount				$ 235
Estimated Useful Life (in years)				7 years
Solebit Labs Ltd. [Member] | Israel [Member]
Business Acquisition [Line Items]
Cash payment				$ 95,700
Business acquisition, agreement date of acquisition				Jul. 31, 2018
Purchase price				$ 96,500
Ataata [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount					$ 1,500
Goodwill					22,600
Ataata [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount					$ 1,400
Estimated Useful Life (in years)					10 years
Ataata [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, amount					$ 100
Estimated Useful Life (in years)					6 years
Ataata [Member] | United States [Member]
Business Acquisition [Line Items]
Business acquisition, effective date of acquisition					Jul. 9, 2018
Cash payment					$ 23,200
Net of cash acquired					$ 1,900
Simply Migrate [Member]
Business Acquisition [Line Items]
Business acquisition, effective date of acquisition			Jan. 25, 2019
Cash payment			$ 7,200
Net of cash acquired			100
Estimated fair values of identifiable intangible assets, amount			3,300
Goodwill			$ 4,300
Simply Migrate [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)			8 years

Acquisitions - Summary of Final

Acquisitions - Summary of Final Purchase Price Allocation (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Purchase consideration:
Total cash paid, net of acquired cash		$ 45,280	$ 115,673	$ 1,381
Fair value of assets acquired and liabilities assumed:
Goodwill		$ 150,525	$ 107,575	$ 5,631
Solebit Labs Ltd. [Member]
Purchase consideration:
Total cash paid, net of acquired cash	$ 85,258
Cash and cash equivalents acquired	10,410
Fair value of previously held asset	828
Total purchase price consideration	96,496
Fair value of assets acquired and liabilities assumed:
Cash and cash equivalents	10,410
Prepaid expenses and other current assets	76
Intangible assets	16,964
Goodwill	74,469
Total assets acquired	101,919
Accounts payable	(18)
Accrued expenses and other current liabilities	(2,345)
Deferred revenue	(663)
Other non-current liabilities	(2,397)
Total fair value of assets acquired and liabilities assumed	$ 96,496

Acquisitions - Summary of Estim

Acquisitions - Summary of Estimated Fair Values and Useful Lives of Identifiable Intangible (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Mar. 31, 2020	Mar. 31, 2019
Developed Technology [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)		8 years	9 years
Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)		5 years	6 years
Trade Names [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)			1 year
Solebit Labs Ltd. [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, Amount	$ 16,964
Solebit Labs Ltd. [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, Amount	$ 16,689
Estimated Useful Life (in years)	10 years
Solebit Labs Ltd. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, Amount	$ 235
Estimated Useful Life (in years)	7 years
Solebit Labs Ltd. [Member] | Trade Names [Member]
Business Acquisition [Line Items]
Estimated fair values of identifiable intangible assets, Amount	$ 40
Estimated Useful Life (in years)	1 year

Acquisitions - Summary of Pro F

Acquisitions - Summary of Pro Forma Financial Information (unaudited) (Detail) - Solebit Labs Ltd. [Member] $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Mar. 31, 2019USD ($)$ / sharesshares
Business Acquisition [Line Items]
Revenue	$ 340,824
Net loss	$ (7,729)
Basic and diluted net loss per share | $ / shares	$ (0.13)
Weighted average number of ordinary shares outstanding
Basic and diluted | shares	59,960

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Goodwill Balance (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Goodwill Roll Forward
Beginning balance	$ 107,575	$ 5,631
Goodwill acquired	42,927	101,381
Effect of foreign exchange rates	23	563
Ending balance	$ 150,525	$ 107,575

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross Carrying Value	$ 50,930	$ 36,519
Accumulated Amortization	(12,536)	(5,896)
Finite-Lived Intangible Assets, Net Carrying Value	$ 38,394	$ 30,623
Developed Technology [Member]
Finite Lived Intangible Assets [Line Items]
Weighted-Average Remaining Useful Life (in years)	8 years	9 years
Finite-Lived Intangible Assets, Gross Carrying Value	$ 33,269	$ 23,577
Accumulated Amortization	(4,547)	(1,707)
Finite-Lived Intangible Assets, Net Carrying Value	$ 28,722	$ 21,870
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Weighted-Average Remaining Useful Life (in years)	5 years	6 years
Finite-Lived Intangible Assets, Gross Carrying Value	$ 771	$ 455
Accumulated Amortization	(159)	(73)
Finite-Lived Intangible Assets, Net Carrying Value	612	$ 382
Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Weighted-Average Remaining Useful Life (in years)		1 year
Finite-Lived Intangible Assets, Gross Carrying Value	41	$ 56
Accumulated Amortization	$ (41)	(34)
Finite-Lived Intangible Assets, Net Carrying Value		$ 22
Capitalized Software and Other [Member]
Finite Lived Intangible Assets [Line Items]
Weighted-Average Remaining Useful Life (in years)	3 years
Finite-Lived Intangible Assets, Gross Carrying Value	$ 16,849
Accumulated Amortization	(7,789)
Finite-Lived Intangible Assets, Net Carrying Value	9,060
Capitalized Software [Member]
Finite Lived Intangible Assets [Line Items]
Weighted-Average Remaining Useful Life (in years)		3 years
Finite-Lived Intangible Assets, Gross Carrying Value		$ 12,431
Accumulated Amortization		(4,082)
Finite-Lived Intangible Assets, Net Carrying Value	$ 9,060	$ 8,349

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Schedule of Intangible Assets (Parenthetical) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Mar. 31, 2019
Video Production Costs [Member]
Finite Lived Intangible Assets [Line Items]
Capitalized software and other cost	$ 1.4	$ 0.5
IP Addresses [Member]
Finite Lived Intangible Assets [Line Items]
Capitalized software and other cost	$ 0.2

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense	$ 7	$ 4.8	$ 1.5

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets - Schedule of Future Estimated Amortization Expense of Acquired Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net Carrying Value	$ 38,394	$ 30,623
Purchased Intangible Assets [Member]
Finite Lived Intangible Assets [Line Items]
2021	3,827
2022	3,827
2023	3,827
2024	3,772
2025	3,701
Thereafter	10,380
Finite-Lived Intangible Assets, Net Carrying Value	29,334
Capitalized Software [Member]
Finite Lived Intangible Assets [Line Items]
2021	3,998
2022	2,701
2023	1,676
2024	395
2025	236
Thereafter	54
Finite-Lived Intangible Assets, Net Carrying Value	$ 9,060	$ 8,349

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Detail) - USD ($)	Mar. 31, 2020	Mar. 31, 2019
Fair Value, Measurements, Recurring [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Assets measured at fair value on a recurring basis		$ 44,289,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Assets measured at fair value on a recurring basis	$ 0	0
Liabilities measured at fair value on a recurring basis	0	0
Strategic Investments [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Equity securities without readily determinable fair value	3,000,000	500,000
Adjustments to carrying value of strategic investment from impairments	$ 0	$ 0

Fair Value Measurement - Summar

Fair Value Measurement - Summary of Financial Assets Measured and Recorded at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Assets:
Total assets		$ 44,289
Money Market Funds [Member]
Assets:
Total assets	$ 17,495	8,348
U.S. Treasury Securities [Member]
Assets:
Total assets		1,994
Non-U.S. Government Securities [Member]
Assets:
Total assets		7,981
Corporate Securities [Member]
Assets:
Total assets		25,966
Quoted Prices in Active Markets for Identical Assets (Level 1 Inputs) [Member]
Assets:
Total assets		8,348
Quoted Prices in Active Markets for Identical Assets (Level 1 Inputs) [Member] | Money Market Funds [Member]
Assets:
Total assets	$ 17,495	8,348
Significant Other Observable Inputs (Level 2 Inputs) [Member]
Assets:
Total assets		35,941
Significant Other Observable Inputs (Level 2 Inputs) [Member] | U.S. Treasury Securities [Member]
Assets:
Total assets		1,994
Significant Other Observable Inputs (Level 2 Inputs) [Member] | Non-U.S. Government Securities [Member]
Assets:
Total assets		7,981
Significant Other Observable Inputs (Level 2 Inputs) [Member] | Corporate Securities [Member]
Assets:
Total assets		$ 25,966

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019		Mar. 31, 2018	Apr. 01, 2019
Lessee Lease Description [Line Items]
Operating and finance leases, existence of option to extend [true false]	true
Operating and finance leases, option to extend, description	some of which include options to extend the leases for up to 10 years.
Operating lease right-of-use assets	$ 116,564,000
Operating lease liabilities	$ 135,700,000
Operating or finance lease, lease not yet commenced, description	the Company had no additional operating or finance leases that have not yet commenced.
Finance lease, lease not yet commenced, value	$ 0
Operating lease, lease not yet commenced, value	0
Rent expense	$ 15,300,000	$ 5,300,000		$ 4,800,000
ASU 2016-02 [Member]
Lessee Lease Description [Line Items]
Operating lease right-of-use assets					$ 141,280,000
Cumulative effect adjustment		$ 2,172,000	[1]		2,200,000
ASU 2016-02 [Member] | Adjustments [Member]
Lessee Lease Description [Line Items]
Operating lease right-of-use assets					141,280,000
Operating lease liabilities					$ 154,700,000
Minimum [Member]
Lessee Lease Description [Line Items]
Operating and finance leases, remaining lease term	1 year
Maximum [Member]
Lessee Lease Description [Line Items]
Operating and finance leases, remaining lease term	10 years
Operating and finance leases, renewal term	10 years
[1]	ASU No. 2016-02, Leases (Topic 842) (ASU 2016-02 or ASC 842)

Leases - Schedule of Impact of

Leases - Schedule of Impact of Adoption of ASC 842 (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Apr. 01, 2019	Mar. 31, 2019
Assets
Prepaid expenses and other current assets	$ 16,145		$ 25,871
Property and equipment, net	85,178		94,202
Operating lease right-of-use assets	116,564
Other assets	3,614		5,156
Liabilities
Accrued expenses and other current liabilities	41,607		44,309
Current portion of operating lease liabilities	30,379
Construction financing lease obligations			36,650
Operating lease liabilities	105,321
Other non-current liabilities	4,386		15,581
Shareholders' equity
Accumulated deficit	$ (83,660)		$ (83,632)
ASU 2016-02 [Member]
Assets
Prepaid expenses and other current assets		$ 24,932
Property and equipment, net		63,239
Operating lease right-of-use assets		141,280
Other assets		2,590
Liabilities
Accrued expenses and other current liabilities		41,061
Current portion of operating lease liabilities		27,611
Operating lease liabilities		127,119
Other non-current liabilities		5,389
Shareholders' equity
Accumulated deficit		(81,460)
ASU 2016-02 [Member] | Adjustments [Member]
Assets
Prepaid expenses and other current assets		(939)
Property and equipment, net		(30,963)
Operating lease right-of-use assets		141,280
Other assets		(2,566)
Liabilities
Accrued expenses and other current liabilities		(3,248)
Current portion of operating lease liabilities		27,611
Construction financing lease obligations		(36,650)
Operating lease liabilities		127,119
Other non-current liabilities		(10,192)
Shareholders' equity
Accumulated deficit		$ 2,172

Leases - Schedule of Components

Leases - Schedule of Components of Lease Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Leases [Abstract]
Short-term lease cost	$ 308
Variable lease cost	4,144
Operating lease cost	37,906
Finance lease cost:
Amortization of lease assets	1,179	$ 1,200	$ 900
Interest on lease liabilities	93
Total finance lease cost	$ 1,272

Leases - Schedule of Supplement

Leases - Schedule of Supplemental Cash Flow Information Related to Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash outflows from operating leases	$ 32,816
Operating cash outflows from finance leases	74
Financing cash outflows from finance leases	$ 844	$ 1,275	$ 1,039

Leases - Schedule of Weighted-a

Leases - Schedule of Weighted-average Remaining Lease Term and Discount Rate (Detail)	Mar. 31, 2020
Leases [Abstract]
Operating leases, Weighted-average remaining lease term	6 years 5 months 15 days
Finance leases, Weighted-average remaining lease term	1 year 3 months 21 days
Operating leases, Weighted-average discount rate	4.74%
Finance leases, Weighted-average discount rate	4.83%

Leases - Schedule of Maturities

Leases - Schedule of Maturities of Lease Liabilities (Detail) $ in Thousands	Mar. 31, 2020USD ($)
Operating Leases
2021	$ 36,231
2022	27,653
2023	21,291
2024	14,741
2025	14,254
Thereafter	43,516
Total lease payments	157,686
Less: imputed interest	(21,986)
Total lease liabilities	135,700
Finance Leases
2021	1,102
2022	326
Total lease payments	1,428
Less: imputed interest	(47)
Total lease liabilities	$ 1,381

Leases - Future Minimum Payment

Leases - Future Minimum Payments for Capital Leases, Facility Operating Leases and Data Center Operating Leases (Detail) $ in Thousands	Mar. 31, 2019USD ($)
Capital Leases Operating Leases And Data Centers [Line Items]
Capital Leases, 2020	$ 918
Capital Leases, 2021	1,102
Capital Leases, 2022	326
Total minimum lease payments	2,346
Less: Amount representing interest	(121)
Present value of capital lease obligations	2,225
Less: Current portion	(844)
Long-term portion of capital lease obligations	1,381
Facility Leases, 2020	10,649
Facility Leases, 2021	15,186
Facility Leases, 2022	14,111
Facility Leases, 2023	13,825
Facility Leases, 2024	13,686
Facility Leases, Thereafter	59,502
Total minimum lease payments	126,959
Data Centers [Member]
Capital Leases Operating Leases And Data Centers [Line Items]
Data Centers, 2020	21,216
Data Centers, 2021	17,427
Data Centers, 2022	13,010
Data Centers, 2023	2,774
Data Centers, 2024	356
Total minimum lease payments	$ 54,783

Debt - Additional Information (

Debt - Additional Information (Detail) - USD ($)	Jul. 23, 2018	Mar. 31, 2020	Mar. 31, 2019
Senior Secured Term Loan [Member]
Debt Instrument [Line Items]
Debt issuance costs		$ 919,000	$ 1,300,000
Outstanding borrowings		93,750,000	98,100,000
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest expense		3,900	3,000
Outstanding borrowings		0	0
Amount available under credit facility		48,000,000	46,100,000
Senior Secured Revolving Credit Facility [Member] | Letter of Credit [Member]
Debt Instrument [Line Items]
Outstanding borrowings		2,000,000	3,900,000
Senior Secured Revolving Credit Facility [Member] | Other Assets [Member]
Debt Instrument [Line Items]
Debt issuance costs		$ 500,000	$ 600,000
Credit Agreement with Certain Lenders [Member]
Debt Instrument [Line Items]
Credit facility term	5 years
Credit facility maturity date	Jul. 23, 2023
Credit facility outstanding debt	$ 0
Credit Agreement with Certain Lenders [Member] | LIBOR Plus [Member]
Debt Instrument [Line Items]
Credit facility current interest rate		1.375%	1.625%
Credit Agreement with Certain Lenders [Member] | Minimum [Member] | LIBOR Plus [Member]
Debt Instrument [Line Items]
Credit facility interest rate	1.375%
Credit Agreement with Certain Lenders [Member] | Maximum [Member] | LIBOR Plus [Member]
Debt Instrument [Line Items]
Credit facility interest rate	1.875%
Credit Agreement with Certain Lenders [Member] | Senior Secured Term Loan [Member]
Debt Instrument [Line Items]
Credit facility amount	$ 100,000,000
Credit Agreement with Certain Lenders [Member] | Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility amount	$ 50,000,000

Debt - Schedule of Future Minim

Debt - Schedule of Future Minimum Principal Payment Obligations (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Debt Instrument [Line Items]
Less: Current portion of long-term debt	$ (6,573)	$ (4,059)
Long-term debt	86,258	92,797
Senior Secured Term Loan [Member]
Debt Instrument [Line Items]
2021	6,875
2022	9,375
2023	10,000
2024	67,500
Total minimum debt payments	93,750	98,100
Less: Debt issuance costs	(919)	$ (1,300)
Less: Current portion of long-term debt	(6,573)
Long-term debt	$ 86,258

Shareholders' Equity - Schedule

Shareholders' Equity - Schedule of Ordinary Share Reserved for Future Issuance (Detail) - shares	Mar. 31, 2020	Mar. 31, 2019
Class of Stock [Line Items]
Options outstanding under share option plans	6,271,111	6,208,964
Unvested RSUs	1,276,840
Total authorized ordinary shares reserved for future issuance	18,289,461
ESPP [Member]
Class of Stock [Line Items]
Total authorized ordinary shares reserved for future issuance	748,903
2015 Plan [Member]
Class of Stock [Line Items]
Options and awards available for future grant under the 2015 Plan	9,992,607

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Detail) $ in Thousands	12 Months Ended
	Mar. 31, 2020USD ($)CompensationPlanInstallmentshares	Mar. 31, 2019USD ($)shares	Mar. 31, 2018USD ($)shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of share-based compensation plans | CompensationPlan	3
Ordinary shares reserved for future issuance | shares	18,289,461
Employee share option agreements, modification expense	$ 100	$ 3,200	$ 500
Total intrinsic value of options exercised	40,000	66,400	74,200
Proceeds from exercises of share-based awards	20,100	21,400	15,600
Share-based compensation expense recognized	39,544	$ 25,954	$ 11,734
Service-Based Vesting Conditions [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 53,700
Unrecognized share-based compensation expense, net of estimated forfeiture, period for recognition	2 years 8 months 4 days
Unvested Restricted Share Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 43,500
Unrecognized share-based compensation expense, net of estimated forfeiture, period for recognition	2 years 11 months 19 days
Unvested Restricted Share Units [Member] | Non-Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, vesting period	3 years
Unvested Restricted Share Units [Member] | Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of vesting installment for equity granted | Installment	4
2015 Plan [Member] | Share Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ordinary shares reserved for future issuance | shares	5,500,000
Increase in number of shares reserved and available for issuance, percentage	5.00%
Share-based compensation arrangement by share-based payment award, term	10 years
Share-based compensation arrangement by share-based payment award, vesting period	4 years
2015 Employee Share Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, term	6 months
Ordinary shares reserved and authorized for issuance | shares	1,100,000
Authorized payroll deductions percentage	10.00%
Percentage of fair market value of shares to be considered as share price	85.00%
Number of shares issued in connection with ESPP | shares	156,000	130,000	64,000
Cash proceeds from shares issued in connection with ESPP	$ 4,900	$ 3,300	$ 1,400
Share-based compensation expense recognized	$ 1,800	$ 1,300	$ 700
2015 Employee Share Purchase Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Authorized payroll deductions percentage	1.00%

Share-Based Compensation - Shar

Share-Based Compensation - Share-Based Compensation Expense Recognized in Statements of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	$ 39,544	$ 25,954	$ 11,734
Cost of Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	3,445	1,684	1,053
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	10,900	6,199	2,555
Sales and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	13,141	7,856	4,477
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	$ 12,058	$ 10,215	$ 3,649

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of Share-Based Compensation, Stock Options, Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Awards, Beginning balance	6,208,964
Number of Awards, Options granted	2,016,318
Number of Awards, Options exercised	(1,359,903)
Number of Awards, Options forfeited and cancelled	(594,268)
Number of Awards, Ending balance	6,271,111	6,208,964
Number of Awards, Exercisable	2,602,224
Weighted Average Exercise Price, Beginning balance	$ 23.47
Weighted Average Exercise Price, Options granted	46.29
Weighted Average Exercise Price, Options exercised	14.81
Weighted Average Exercise Price, Options forfeited and cancelled	35.39
Weighted Average Exercise Price, Ending balance	31.61	$ 23.47
Weighted Average Exercise Price Exercisable	$ 20.43
Weighted Average Remaining Contractual Term, Outstanding	7 years 6 months 18 days	7 years 6 months 29 days
Weighted Average Remaining Contractual Term, Exercisable	6 years 2 months 26 days
Aggregate Intrinsic Value, Outstanding	$ 47,621	$ 148,313
Aggregate Intrinsic Value, Exercisable	$ 40,224

Share-Based Compensation - Sc_2

Share-Based Compensation - Schedule of Share-Based Compensation, RSUs, Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Mar. 31, 2020USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares Unvested, RSUs Begining balance
Number of Shares, Unvested RSUs, Ending balance	1,276,840
Restricted Share Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares Unvested, RSUs Begining balance	549,853
Number of Shares, RSUs granted	1,015,290
Number of Shares, RSUs vested	(161,450)
Number of Shares, RSUs forfeited	(126,853)
Number of Shares, Unvested RSUs, Ending balance	1,276,840
Weighted Average Grant Date Fair Value, Unvested RSUs, Beginning balance | $ / shares	$ 37.15
Weighted Average Grant Date Fair Value, RSUs granted | $ / shares	46.17
Weighted Average Grant Date Fair Value, RSUs vested | $ / shares	37.04
Weighted Average Grant Date Fair Value, RSUs forfeited | $ / shares	44.08
Weighted Average Grant Date Fair Value, Unvested RSUs, Ending balance | $ / shares	$ 43.64
Intrinsic Value, Unvested RSUs, Beginning balance | $	$ 26,036
Intrinsic Value, Unvested RSUs, Ending Balance | $	$ 45,072

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - Patented Technology [Member] - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Commitments And Contingencies [Line Items]
Incremental expense	$ 2.7	$ 1
Aggregate payment of litigation settlement	5.9
Remaining amortization expense	$ 2.2
Weighted-Average Remaining Useful Life (in years)	3 years 6 months

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Defined Contribution Plan Disclosure [Line Items]
Matching or profit sharing contributions to 401(k) plan by employer	$ 1,600,000	$ 1,200,000	$ 0
Contribution expense	$ 600,000
United Kingdom [Member]
Defined Contribution Plan Disclosure [Line Items]
Additional contribution percentage by the company	3.50%
Contribution expense	$ 1,900,000	$ 1,500,000	$ 500,000
South Africa [Member]
Defined Contribution Plan Disclosure [Line Items]
Additional contribution percentage by the company	5.00%
Germany [Member]
Defined Contribution Plan Disclosure [Line Items]
Additional contribution percentage by the company	3.00%
Netherlands [Member]
Defined Contribution Plan Disclosure [Line Items]
Additional contribution percentage by the company	3.00%

Segment and Geographic Inform_3

Segment and Geographic Information - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2020Segment
Segment Reporting [Abstract]
Number of operating segment	1

Segment and Geographic Inform_4

Segment and Geographic Information - Summary of Revenue by Geographic Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	$ 426,963	$ 340,377	$ 261,897
United States [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	219,423	169,286	128,503
United Kingdom [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	123,620	103,900	81,720
South Africa [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	51,549	46,275	39,425
Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	$ 32,371	$ 20,916	$ 12,249

Segment and Geographic Inform_5

Segment and Geographic Information - Summary of Property and Equipment, Net by Geographic Location (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	$ 85,178	$ 94,202
United States [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	39,193	62,455
United Kingdom [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	29,644	17,402
South Africa [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	7,093	6,170
Other [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	$ 9,248	$ 8,175

Segment and Geographic Inform_6

Segment and Geographic Information - Summary of Property and Equipment, Net by Geographic Location (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	$ 85,178	$ 94,202
United States [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	$ 39,193	62,455
United States [Member] | Construction Costs Capitalized under Financing Lease Obligations Related to Build-to-suit Facility [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net		$ 41,837

Income Taxes - Summary of Incom

Income Taxes - Summary of Income (Loss) Before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
United Kingdom	$ (20,528)	$ (4,626)	$ (15,939)
Foreign	20,687	(374)	6,258
Income (loss) before income taxes	$ 159	$ (5,000)	$ (9,681)

Income Taxes - Schedule of Prov

Income Taxes - Schedule of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Domestic	$ 0	$ 0	$ 0
Foreign	2,939	3,493	2,597
Total current tax expense	2,939	3,493	2,597
Domestic	0	(578)	0
Foreign	(580)	(914)	108
Total deferred tax (benefit) expense	(580)	(1,492)	108
Total provision for income taxes	$ 2,359	$ 2,001	$ 2,705

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Statutory Tax Rate to Effective Tax Rate (Detail)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Tax at statutory rate	19.00%	19.00%	19.00%
U.S. state taxes, net of federal	558.00%	31.10%	14.10%
Foreign rate differential	291.50%	26.30%	36.80%
Meals and entertainment	432.60%	(11.40%)	(3.10%)
Branch (income) loss	(69.90%)	(0.60%)	0.40%
Share-based compensation	(2341.90%)	172.30%	105.30%
Tax credits	(375.50%)	7.70%	8.10%
Unremitted earnings	101.30%	(3.80%)	(1.20%)
Change in valuation allowance	(1456.80%)	(249.90%)	(110.70%)
Deferred tax true-ups	116.20%	(3.50%)	8.40%
Tax reserves	3147.40%	(4.90%)	(21.50%)
Provision to return	37.60%	(0.10%)	0.40%
Withholding taxes	323.50%	(2.60%)	(3.50%)
Non-deductible expenses	197.70%	(5.20%)	(2.40%)
Deferred tax rate change	473.10%	(6.30%)	(77.80%)
Acquisition-related costs	91.70%	(7.60%)
Foreign exchange	(59.50%)
Other	(2.40%)	(0.50%)	(0.20%)
Effective Tax Rate	1483.60%	(40.00%)	(27.90%)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Taxes [Line Items]
Tax at statutory rate	19.00%	19.00%	19.00%
Liabilities for uncertain tax positions	$ 10,400,000	$ 6,000,000
Liabilities for uncertain tax positions, if recognized having impact on effective tax rate	0	$ 0
Unremitted foreign earnings	47,800,000
Unremitted foreign earnings for income taxes have been provided	14,200,000
Unremitted foreign earnings for income taxes have not been provided	33,500,000
U. K. [Member] | Domestic Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	70,200,000
Tax Credit Carryforward, Amount	1,400,000
U.S. Federal [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	69,400,000
U.S. State [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 33,900,000
Net operating loss carryforwards, expiration year	2040
Australian [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 22,000,000
German [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	9,900,000
Israeli [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	9,700,000
Tax Credit Carryforward, Amount	900,000
Dutch [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 800,000
Minimum [Member] | Israeli [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Tax credit carryforward, expiration year	2023
Minimum [Member] | Dutch [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards, expiration year	2026
Maximum [Member] | Israeli [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Tax credit carryforward, expiration year	2025
Maximum [Member] | Dutch [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards, expiration year	2028
Expires at Various Dates [Member] | U.S. Federal [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 51,400,000
Net operating loss carryforwards, expiration year	2038
Do Not Expire [Member] | U.S. Federal [Member] | Foreign Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 18,000,000
ASU 2016-09 [Member]
Income Taxes [Line Items]
Net decrease in valuation allowance	$ 4,100,000

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and (Liabilities) (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Deferred tax assets:
Net operating loss carryforwards	$ 30,879	$ 35,120
Share-based compensation	9,501	5,687
Deferred revenue	2,315	1,761
Fixed assets	4,718	4,187
Lease liability	30,890	11,748
Accrued compensation	1,786	1,211
Deferred rent		320
Income tax credits	2,311	1,833
Other	2,042	1,648
Gross deferred tax assets	84,442	63,515
Deferred tax liabilities:
Fixed assets	(7,414)	(13,855)
Unremitted earnings	(362)	(320)
Intangible assets	(6,453)	(4,818)
Capitalized commissions	(9,751)	(7,606)
Right-of-use asset	(26,498)
Other	(2,145)	(606)
Gross deferred tax liabilities	(52,623)	(27,205)
Valuation allowance	(34,224)	(38,318)
Deferred tax liabilities, net	$ (2,405)	$ (2,008)

Income Taxes - Summary of Recon

Income Taxes - Summary of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Beginning balance	$ 6,016	$ 6,164
Additions based on tax positions related to current year	535	164
Additions for tax positions of prior years	4,235	231
Reductions due to change in foreign exchange rate	(431)	(301)
Expiration of statutes of limitation		(165)
Reductions due to settlements with tax authorities		(77)
Ending balance	$ 10,355	$ 6,016

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - $ / shares	Apr. 01, 2020	Mar. 31, 2020
Subsequent Event [Line Items]
Options granted		2,016,318
Share Options [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Options granted	800,000
Grant date fair value of options	$ 14.29
Restricted Share Units (RSUs) [Member]
Subsequent Event [Line Items]
Number of Shares, Restricted share units granted		1,015,290
Restricted Share Units (RSUs) [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Number of Shares, Restricted share units granted	1,600,000
Grant date fair value of restricted share units	$ 33.38

Quarterly Results of Operatio_3

Quarterly Results of Operations Data (Unaudited) - Summary of Quarterly Results of Operations Data (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 114,217	$ 110,158	$ 103,357	$ 99,231	$ 92,193	$ 87,611	$ 82,169	$ 78,404
Gross profit	84,891	81,703	77,223	73,764	67,491	64,353	60,231	57,428	$ 317,581	$ 249,503	$ 192,198
Income (loss) from operations	5,125	1,629	(18)	(4,438)	207	1,572	(909)	(2,089)	2,298	(1,219)	(6,954)
Net income (loss)	$ 2,525	$ 206	$ (921)	$ (4,010)	$ (1,930)	$ 458	$ (2,058)	$ (3,471)	$ (2,200)	$ (7,001)	$ (12,386)
Net income (loss) per ordinary share:
Basic	$ 0.04	$ 0	$ (0.01)	$ (0.07)	$ (0.03)	$ 0.01	$ (0.03)	$ (0.06)
Diluted	$ 0.04	$ 0	$ (0.01)	$ (0.07)	$ (0.03)	$ 0.01	$ (0.03)	$ (0.06)
Weighted-average number of ordinary shares outstanding
Basic	62,636	62,189	61,829	61,444	60,733	60,141	59,800	59,175
Diluted	64,382	63,996	61,829	61,444	60,733	62,537	59,800	59,175