Nimble Storage (NMBL) 10-K 2 Apr 15 2015 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, unless otherwise specified	Jan. 31, 2015	Mar. 25, 2015	Jul. 31, 2014
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Jan-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Trading Symbol	NMBL
Entity Registrant Name	Nimble Storage Inc
Entity Central Index Key	1452751
Current Fiscal Year End Date	-30
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		77.5
Entity Public Float			$25.60

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Jan. 31, 2015	Jan. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$208,394	$208,486
Accounts receivable, net of allowance for doubtful accounts of $0 and $76 as of January 31, 2015 and 2014, respectively	35,271	17,676
Inventories	11,981	5,412
Prepaid expenses and other current assets	4,974	3,176
Total current assets	260,620	234,750
Property and equipment, net	36,716	20,209
Restricted cash, non-current	3,983	3,900
Other long-term assets	255	212
Total assets	301,574	259,071
Current liabilities:
Accounts payable	19,799	9,093
Accrued compensation and benefits	21,128	9,837
Deferred revenue, current portion	34,246	16,178
Other current liabilities	8,063	3,855
Total current liabilities	83,236	38,963
Deferred revenue, non-current portion	40,200	17,331
Other long-term liabilities	9,566	11,091
Total liabilities	133,002	67,385
Commitments and contingencies (Note 6)
Stockholders' equity:
Preferred stock, par value of $0.001 per share; 5,000 shares authorized, no shares issued and outstanding as of January 31, 2015 and 2014	0	0
Common stock, par value of $0.001 per share; 750,000 shares authorized as of January 31, 2015 and 2014, respectively; 76,191 and 71,643 shares issued and outstanding as of January 31, 2015 and 2014, respectively	71	67
Additional paid-in capital	368,689	292,686
Accumulated other comprehensive income (loss)	-250	25
Accumulated deficit	-199,938	-101,092
Total stockholders' equity	168,572	191,686
Total liabilities and stockholders' equity	$301,574	$259,071

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Jan. 31, 2015	Jan. 31, 2014
In Thousands, except Per Share data, unless otherwise specified
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$0	$76
Preferred stock, par value	$0.00	$0.00
Preferred stock, shares authorized	5,000	5,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	750,000	750,000
Common stock, shares issued	76,191	71,643
Common stock, shares outstanding	76,191	71,643

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Revenue:
Product	$198,129	$112,812	$49,765
Support and service	29,544	12,921	4,075
Total revenue	227,673	125,733	53,840
Cost of revenue:
Product	62,780	36,231	17,266
Support and service	16,173	7,980	3,184
Total cost of revenue	78,953	44,211	20,450
Gross profit	148,720	81,522	33,390
Operating expenses:
Research and development	70,338	35,247	16,135
Sales and marketing	143,575	75,107	39,851
General and administrative	30,884	13,737	5,168
Total operating expenses	244,797	124,091	61,154
Loss from operations	-96,077	-42,569	-27,764
Interest income, net	139	21	32
Other expense, net	-2,071	-150	-26
Loss before provision for income taxes	-98,009	-42,698	-27,758
Provision for income taxes	837	425	99
Net loss	-98,846	-43,123	-27,857
Accretion of redeemable convertible preferred stock	0	-36	-34
Net loss attributable to common stockholders	($98,846)	($43,159)	($27,891)
Net loss per share attributable to common stockholders, basic and diluted	($1.37)	($1.61)	($1.53)
Weighted-average shares used to compute net loss per share attributable to common stockholders, basic and diluted	72,304	26,772	18,236

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Loss (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Statement of Comprehensive Income [Abstract]
Net loss	($98,846)	($43,123)	($27,857)
Other comprehensive income (loss), net of taxes:
Change in cumulative translation adjustment	-275	8	17
Comprehensive loss	($99,121)	($43,115)	($27,840)

Consolidated_Statements_of_Red

Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (USD $)	Total	Initial Public Offering [Member]	Redeemable Convertible Preferred Stock [Member]	Redeemable Convertible Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member]	Notes Receivable from Stockholders [Member]	Accumulated Other Comprehensive Income (Deficit) [Member]	Accumulated Deficit [Member]
In Thousands, except Share data				Series E Redeemable Convertible Preferred Stock [Member]		Initial Public Offering [Member]		Initial Public Offering [Member]
Beginning balance at Jan. 31, 2012	($29,741)		$57,921		$11		$1,403		($1,043)		($30,112)
Beginning balance, Shares at Jan. 31, 2012			34,620,000		19,128,000
Issuance of Series E redeemable convertible preferred stock for cash, net of issuance costs of $96				40,604
Issuance of Series E redeemable convertible preferred stock for cash, net of issuance costs of $96, Shares				4,248,000
Accretion of redeemable convertible preferred stock to redemption value	-34		34				-34
Issuance of common stock upon exercise stock options, net of repurchases	881				6		875
Issuance of common stock upon exercise stock options, net of repurchases, Shares					2,260,000
Notes receivable from stockholders	-519								-519
Vesting of early exercise of stock options	987						987
Stock-based compensation	2,604						2,604
Net loss	-27,840									17	-27,857
Ending balance at Jan. 31, 2013	-53,662		98,559		17		5,835		-1,562	17	-57,969
Ending balance, Shares at Jan. 31, 2013			38,868,000		21,388,000
Accretion of redeemable convertible preferred stock to redemption value	-36		36				-36
Issuance of common stock upon initial public offering, net of issuance costs of $3,973		175,702				9		175,693
Issuance of common stock upon initial public offering, net of issuance costs of $3,973, Shares						9,200,000
Conversion of preferred stock into shares of common stock	98,595		-98,595		39		98,556
Conversion of preferred stock into shares of common stock, Shares			-38,868,000		38,868,000
Issuance of common stock upon exercise stock options, net of repurchases	1,486				2		1,484
Issuance of common stock upon exercise stock options, net of repurchases, Shares					2,187,000
Repayment of notes receivable from stockholders	1,562								1,562
Vesting of early exercise of stock options	2,005						2,005
Stock-based compensation	9,149						9,149
Net loss	-43,115									8	-43,123
Ending balance at Jan. 31, 2014	191,686				67		292,686			25	-101,092
Ending balance, Shares at Jan. 31, 2014					71,643,000
Issuance costs for initial public offering	-283						-283
Issuance of common stock upon exercise stock options, net of repurchases	7,674				3		7,671
Issuance of common stock upon exercise stock options, net of repurchases, Shares	3,543,000				3,508,000
Issuance of common stock for settlement of restricted stock units (RSUs)	0		0		0		0		0	0	0
Issuance of common stock for settlement of restricted stock units (RSUs), Shares					532,000
Shares withheld related to net share settlement of RSUs	-125						-125
Shares withheld related to net share settlement of RSUs, Shares					-3,000
Issuance of common stock under employee stock purchase plan	9,227				1		9,226
Issuance of common stock under employee stock purchase plan, Shares					511,000
Vesting of early exercise of stock options	2,340						2,340
Tax benefit from employee stock plans	163						163
Stock-based compensation	57,011						57,011
Net loss	-99,121									-275	-98,846
Ending balance at Jan. 31, 2015	$168,572				$71		$368,689			($250)	($199,938)
Ending balance, Shares at Jan. 31, 2015					76,191,000

Consolidated_Statements_of_Red1

Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2013	Jan. 31, 2014
Series E Redeemable Convertible Preferred Stock [Member]
Issuance costs	$96
Initial Public Offering [Member]
Issuance costs		$3,973

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Cash flows from operating activities:
Net loss	($98,846)	($43,123)	($27,857)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation	8,753	4,177	1,118
Stock-based compensation expense	57,067	9,149	2,604
Loss on disposal of property and equipment	0	148	0
Provision (recoveries) for allowance for doubtful accounts	-32	104	0
Provision (recoveries) for excess and obsolete inventories	-101	252	421
Changes in operating assets and liabilities:
Accounts receivable	-17,563	-4,055	-9,187
Inventories	-6,158	-1,305	-3,043
Prepaid expenses and other assets	-1,841	-2,182	-570
Accounts payable	8,451	333	4,318
Deferred revenue	40,937	22,613	8,868
Accrued and other liabilities	14,709	7,147	4,574
Net cash provided by (used in) operating activities	5,376	-6,742	-18,754
Cash flows from investing activities:
Purchase of property and equipment	-20,820	-13,613	-3,954
Proceeds from sale of property and equipment	0	27	0
Change in restricted cash	-83	-3,900	400
Net cash used in investing activities	-20,903	-17,486	-3,554
Cash flows from financing activities:
Proceeds from issuance of common stock, net of issuance costs	-1,310	176,729	0
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs	0	0	40,604
Proceeds from exercise of stock options, net of repurchases	7,729	5,201	2,096
Proceeds from issuance of stock under employee stock purchase plan	9,227	0	0
Excess tax benefit from employee stock plans	163	0	0
Proceeds from repayment of loans from stockholders	0	1,571	0
Payment of taxes related to net settlement of restricted stock units	-125	0	0
Net cash provided by financing activities	15,684	183,501	42,700
Foreign exchange impact on cash and cash equivalents	-249	8	17
Net increase (decrease) in cash and cash equivalents	-92	159,281	20,409
Cash and cash equivalents, beginning of period	208,486	49,205	28,796
Cash and cash equivalents, end of period	208,394	208,486	49,205
Supplemental disclosure of cash flow information:
Cash paid for income taxes	394	37	0
Cash paid for interest	23	0	0
Supplemental disclosure of noncash investing and financing activities:
Increase in accounts payable and accrued liabilities related to property and equipment purchase	4,776	6,888	0
Vesting of early exercised stock options	2,340	2,005	987
Conversion of preferred stock to common stock upon IPO	0	98,595	0
Deferred offering costs	0	1,027	0
Accretion of redeemable convertible preferred stock	0	36	34
Issuance of employee loan for stock options exercised	$0	$0	$439

Description_of_Business_and_Ba

Description of Business and Basis of Presentation	12 Months Ended
	Jan. 31, 2015
Accounting Policies [Abstract]
Description of Business and Basis of Presentation	1. Description of Business and Basis of Presentation
	Description of Business
	Nimble Storage, Inc. (the Company) was incorporated in the state of Delaware in November 2007. The Company’s mission is to provide its customers with the industry’s most efficient data storage platform. The Company has designed and sells a flash-optimized storage platform, Adaptive Flash, that it believes is disrupting the market by enabling significant improvements in application performance and storage capacity with superior data protection, while simplifying business operations and lowering costs. With the combination of the Company’s file system, CASL, and its cloud-based storage management and support service, InfoSight, the Company’s platform serves a broad array of enterprises and cloud-based service providers, and the Company’s software and storage systems effectively handle mainstream applications, including virtual desktops, databases, email, collaboration and analytics. The Company is headquartered in San Jose, California, with employees in several international locations, including the United Kingdom, Australia, Canada, Germany, and Singapore.
	Basis of Presentation and Consolidation
	The consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and include the consolidated accounts of the Company and its subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Jan. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies
	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Such estimates include, but are not limited to, the determination of the best estimated selling prices of deliverables included in multiple-deliverable revenue arrangements; the allowance for doubtful accounts; provision for excess or obsolete inventory; the useful lives of property and equipment; the warranty reserve; and the fair value of the Company’s common stock and stock options issued. Actual results could differ from these estimates.
	Concentrations
	The Company’s financial instruments that are exposed to concentrations of credit risk are primarily cash and cash equivalents and trade accounts receivable. Cash and cash equivalents are maintained primarily at one financial institution, and deposits may exceed the amount of insurance provided on such deposits. Risks associated with cash and cash equivalents are mitigated by banking with a creditworthy institution. The Company has not experienced any losses on its deposits of cash and cash equivalents.
	The Company performs ongoing credit evaluations of its customers’ financial condition whenever deemed necessary and generally does not require collateral. The Company maintains an allowance for doubtful accounts based upon the expected collectability of its accounts receivable, which takes into consideration specific customer creditworthiness and current economic trends. During the third and fourth quarters of the year ended January 31, 2014, the Company consolidated the majority of its North American sales to two distributors, and as a result, accounts receivable and revenue increased in concentration. The majority of previous value added resellers (VARs) are now purchasing from these two distributors. Of all the Company’s customers, which include direct end-customers, VARs and distributors, the following customers individually accounted for more than 10% of the Company’s accounts receivable and revenue at the end of and for each period presented:
			% of Accounts Receivable								% of Revenue
			As of January 31,								Year Ended January 31,
			2015			2014					2015			2014			2013
	Customer A			44	%		47	%				48	%		16	%		*
	Customer B			18	%		*					*			*			*
	Customer C			16	%		21	%				21	%		*			*
	Customer D			*			10	%				*			*			*
	Customer E			*			*					*			*			15	%
	*	Represents less than 10%.
	There are no concentrations of business transacted with a particular market that would severely impact the Company’s business in the near term. However, the Company currently relies on one key contract manufacturer and supplier to produce most of its products; any disruption or termination of these arrangements could materially adversely affect the Company’s operating results.
	Foreign Currency Translation and Transactions
	The functional currency of each of the Company’s foreign subsidiaries is its respective local currency. The Company translates all monetary assets and liabilities denominated in foreign currencies into U.S. dollars using the exchange rates in effect at the balance sheet dates and other assets and liabilities using historical exchange rates. Revenue and expenses are translated at average exchange rates in effect during the year. Translation adjustments are recorded within accumulated other comprehensive income (loss), a separate component of stockholders’ equity.
	Foreign currency denominated transactions are initially recorded and re-measured at the end of each period using the applicable exchange rate in effect. Foreign currency re-measurement losses are recognized in other expense, net, in the consolidated statements of operations. Foreign currency re-measurement net losses recognized were $2.1 million, $149,000, and $26,000 for the years ended January 31, 2015, 2014, and 2013, respectively. For the year ended January 31, 2015, the $2.1 million net losses from foreign currency remeasurement included $0.7 million gains related to foreign currency forward contracts.
	Fair Value
	The carrying value of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximates fair value.
	Cash and Cash Equivalents
	The Company considers all highly liquid investments with an original maturity of 90 days or less at the date of purchase to be cash equivalents. Cash and cash equivalents consist principally of cash accounts and investments in money market funds.
	Restricted Cash
	As a condition of the Company’s headquarters facility lease agreement, the Company is required to maintain a letter of credit of $3.9 million, with the landlord named as the beneficiary. These restricted cash balance have been excluded from the Company’s cash and cash equivalents balance and are classified as restricted cash on the Company’s consolidated balance sheets. As of January 31, 2015 and 2014, the amount of restricted cash was $4.0 million and $3.9 million, respectively, and classified as non-current (see Note 6).
	Accounts Receivable
	Accounts receivable are recorded at the invoiced amounts and do not bear interest. The Company maintains an allowance for doubtful accounts for estimated losses inherent in its accounts receivable portfolio. An allowance for doubtful accounts is calculated based on the aging of the Company’s trade receivables, historical experience, and management judgment. The Company writes off trade receivables against the allowance when management determines a balance is uncollectible and no longer actively pursues collection of the receivable. As of January 31, 2015 and 2014, the allowance for doubtful accounts was $0 and $76,000, respectively.
	Inventories
	Inventories consist primarily of raw materials related to component parts, finished goods, which include both inventory held for sale and service inventory held at service depots in support of customer service agreements, and customer evaluation inventory.
	The following is a summary of the Company’s inventories by major category (in thousands):
			As of January 31,
			2015			2014
	Raw materials		$	2,383		$	679
	Finished goods			6,871			3,605
	Evaluation inventory			2,727			1,128
			$	11,981		$	5,412
	Inventory values are stated at the lower of cost (on a first-in, first-out method), or market value. A provision is recorded to adjust inventory to its estimated realizable value when inventory is determined to be in excess of anticipated demand or obsolete. In determining the provision, the Company also considers estimated recovery rates based on the nature of the inventory. Service inventory is written down to its net realizable value based upon the estimated loss of utility starting from the date the service inventory is placed in the service depots. Customer evaluation inventory is written down to its net realizable value based upon its estimated loss of utility, starting from 180 days after the unit is placed in the evaluation pool, which is the expected life of the finished goods in the evaluation pool.
	The Company recorded inventory recoveries of $101,000 and inventory provisions of $252,000 and $421,000 for the years ended January 31, 2015, 2014 and 2013, respectively.
	Property and Equipment
	Property and equipment are stated at cost, net of accumulated depreciation. Demonstration units are not sold and are transferred from inventory at cost. Depreciation is computed using the straight-line method over the following estimated useful lives:
	Property and Equipment		Useful Life
	Computer equipment, lab equipment and software		3 years
	Furniture and fixtures		5 years
	Leasehold improvements		Shorter of estimated useful life or remaining lease term
	Demonstration equipment		2 years
	Repairs and maintenance are expensed as incurred.
	Impairment of Long-Lived Assets
	The Company evaluates events and changes in circumstances that could indicate carrying amounts of long-lived assets, including property and equipment, may not be recoverable. When such events or changes in circumstances occur, the Company assesses the recoverability of long-lived assets by determining whether or not the carrying value of such assets will be recovered through undiscounted expected future cash flows. If the total of the future undiscounted cash flows is less than the carrying amount of an asset, the Company records an impairment charge for the amount by which the carrying amount of the assets exceeds the fair value of the asset. Through January 31, 2015, the Company had not written down any of its long-lived assets as a result of impairment.
	Warranties
	The Company provides a standard one-year warranty for hardware components covering material defects in materials and workmanship. In addition, the Company provides a 90-day warranty on the embedded software in its products for non-conformance with documented specifications. The Company accrues for estimated warranty costs based upon historical experience, and periodically assesses the adequacy of its recorded warranty liability at the end of each period. These costs are expensed as incurred and included in cost of product revenue in the Company’s consolidated statements of operations. The Company records warranty liability in other current liabilities in its consolidated balance sheet.
	The table below summarizes the activity in the warranty accrual (in thousands):
			Year Ended January 31,
			2015			2014
	Beginning balance		$	537		$	275
	Warranty expense for new warranties issued			1,372			1,432
	Utilization of warranty obligation			(1,233	)		(1,181	)
	Changes in estimates for pre-existing warranties			(485	)		11
	Ending balance		$	191		$	537
	Revenue Recognition
	The Company generates revenue from sales of software-enabled storage products and related support. The Company’s software that is integrated on the storage products is more than incidental, and functions together with the storage product to deliver its essential functionality. The Company also offers an optional support plan (typically one to five years). The support plan includes automated support (Proactive Wellness), bug fixes, updates and upgrades to product firmware and the Company’s management platform, including InfoSight, telephone support and expedited delivery times for replacement hardware parts. While support is not contractually mandatory, substantially all products shipped have been purchased together with a support plan. The Company also periodically sells optional installation services with its products that are not essential to the functionality of the storage product.
	Substantially all of the Company’s customer arrangements contain multiple deliverables. As a result, the Company accounts for the revenue for these sales in accordance with Accounting Standards Codification (ASC) 605-25 Revenue Recognition – Multiple Element Arrangements. Arrangements are divided into separate units of accounting based on whether the delivered items have stand-alone value. In its typical customer arrangements, the Company considers the following to be separate units of accounting: the storage product (together with the integrated software), support services and installation services. The Company has determined that each unit of accounting has stand-alone value because they are sold separately by the Company or could be resold by a customer on a stand-alone basis. The Company allocates the total consideration to all deliverables based on its determination of the units of accounting and their relative selling prices.
	As the Company has not yet established vendor-specific objective evidence (VSOE) or identified third-party evidence of fair value for its storage product (together with the integrated software) and installation services, it uses the best estimate of the selling price (BESP) of each deliverable to allocate the total arrangement fee among the separate units of accounting. The Company’s process to determine its BESP for its products and services is based on qualitative and quantitative considerations of multiple factors, which primarily include historical stand-alone sales, margin objectives, and discount behavior. Additional considerations are given to factors such as customer demographics, competitive alternatives, anticipated sales volume, costs to manufacture products or provide services, pricing practices, and market conditions. During the second quarter of the year ended January 31, 2013, the Company established VSOE of fair value for support services based on stand-alone renewals offered to its customers. As a result, beginning in the second quarter of the year ended January 31, 2013, the Company allocated the fair value of consideration related to support services based on VSOE of fair value for its support services. Prior to this change, the Company allocated consideration related to support services based on BESP. The effect of the change from BESP to VSOE of fair value for support services did not have a material impact on the allocation of consideration.
	Revenue is recognized when all of the following criteria are met:
		•		Persuasive Evidence of an Arrangement Exists. The Company relies upon non-cancelable sales agreements and purchase orders to determine the existence of an arrangement.
	•		Delivery Has Occurred. The Company uses shipping documents to verify delivery.
	•		The Fee Is Fixed or Determinable. The Company assesses whether the fee is fixed or determinable based on the payment terms associated with the transaction.
	•		Collectability Is Reasonably Assured. The Company assesses collectability based on credit analysis and payment history.
It is the Company’s practice to identify a direct customer or an end-customer from its VARs and distributors prior to shipment. In the majority of instances, products are shipped directly to the direct customer or the end-customers. For a certain end-customer orders, products are shipped to resellers, distributors and third-party systems integrators for various reasons including importing of products to non-U.S. countries and systems integration (e.g. SmartStack integrations) prior to shipment to the end-customer or the end-customer specified location. Assuming all other revenue recognition criteria have been met, the Company generally recognizes revenue upon shipment, as title and risk of loss are transferred at that time. For certain VARs and distributors, title and risk of loss is transferred upon delivery to the end-customer and revenue is recognized after delivery has been completed. The Company’s arrangements with VARs and distributors do not contain rights of return, subsequent price discounts, price protection or other allowances for shipments completed.
The majority of the Company’s deferred revenue consists of the unrecognized portion of revenue from sales of its support and service contracts. The Company records amounts to be recognized during the twelve months following the balance sheet date in deferred revenue, current portion in the consolidated balance sheets, and the remainder in deferred revenue, non-current portion in the consolidated balance sheets. As of January 31, 2015, the weighted average remaining contract period related to non-current deferred revenue was approximately 2.2 years.
In November 2014, the Company announced its Storage on Demand (SoD) service offering, for enterprises and service providers managing storage in cloud environments. Under this pay-as-you-go subscription model, customers are generally billed on a monthly basis based on the amount of data consumed during the month. The SoD service offering includes all support services such as InfoSight. Revenue is recognized as services are performed. SoD revenue is recognized in support and service revenue in the consolidated statements of operations.
Shipping Costs
Shipping charges billed to customers are included in product revenue and the related shipping and handling costs are included in cost of revenue.
Research and Development
Research and development expense consists of personnel costs, including stock-based compensation expense, for the Company’s research and development personnel and product development costs, including engineering services, development software and hardware tools, depreciation of capital equipment and facility costs. Research and development costs are expensed as incurred.
Advertising Costs
Advertising costs are expensed as incurred and are included in sales and marketing expense. Advertising costs for the years ended January 31, 2015, 2014 and 2013 were $3.0 million, $1.2 million and $0.4 million, respectively.
Stock-Based Compensation
Prior to the Company’s initial public offering on December 13, 2013, the Company’s board of directors determined the fair value of its common stock using various valuation methodologies, including valuation analyses performed by third-party valuation firms. After the initial public offering, the Company used the publicly quoted price as the fair value of its common stock.
The Company determines the fair value of its stock options and shares of common stock to be issued related to its employee stock purchase plan (ESPP) on the date of grant utilizing the Black-Scholes-Merton option-pricing model, and is impacted by the fair value of its common stock, as well as changes in assumptions regarding a number of highly complex and subjective variables. These variables include, but are not limited to, the expected common stock price volatility over the term of the option awards, the expected term of the awards, risk-free interest rates and expected dividend yield. The Company generally recognizes compensation expense for stock option grants and ESPP on a straight-line basis over the requisite service period, which is generally four years for stock options, and six months to two years for ESPP. Stock-based compensation expense recognized at fair value includes the impact of estimated forfeitures.
Stock-based compensation cost for restricted stock units (RSUs) is measured based on the fair value of the underlying shares on the date of grant. The RSUs generally vest over the requisite service period. The fair value of RSUs is determined by the estimated fair value of the Company’s common stock at the time of grant. Stock-based compensation expense is recognized at fair value and includes the impact of estimated forfeitures.
Income Taxes
The Company accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using the enacted tax rates in effect for the years in which the temporary differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected to be realized.
Derivative Financial Instruments
During the year ended January 31, 2015, the Company entered into foreign currency forward contracts to minimize the short-term impact of foreign currency exchange rate fluctuations on cash and certain trade and inter-company receivables and payables. These contracts reduce the exposure to fluctuations in foreign currency exchange rate movements as the gains and losses associated with foreign currency balances are offset with the gains and losses on the forward contracts. The Company does not enter into foreign currency forward contracts for trading or speculative purposes. These instruments are marked to market through earnings every period and generally are one month in original maturity. The net gain or loss from the settlement of these foreign currency forward contracts is recorded in other expense, net in the consolidated statements of operations.
Net Loss Per Share Attributable to Common Stockholders
Prior to the Company’s initial public offering on December 13, 2013, the Company calculated its basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for companies with participating securities. The Company considers all series of its redeemable convertible preferred stock to be participating securities. In the event a dividend is declared or paid on the Company’s common stock, holders of redeemable convertible preferred stock are entitled to a proportionate share of such dividend in proportion to the holders of common stock on an as-if converted basis. Under the two-class method, basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period, less shares subject to repurchase. Net loss attributable to common stockholders is determined by allocating undistributed earnings between common and redeemable convertible preferred stockholders. The diluted net loss per share attributable to common stockholders is computed by giving effect to all potential dilutive common stock equivalents outstanding for the period. For purposes of this calculation, redeemable convertible preferred stock, options to purchase common stock, repurchasable shares from early exercised options, unvested RSUs and shares subject to ESPP withholding are considered common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as their effect is antidilutive. Under the two-class method, the net loss attributable to common stockholders is not allocated to the convertible redeemable preferred stock as the convertible redeemable preferred stock do not have a contractual obligation to share in the Company’s losses.
On December 13, 2013, all shares of redeemable convertible preferred stocks were converted to common stock.
The following table sets forth the computation of net loss per share (in thousands, except per share amounts):
		Year Ended January 31,
		2015			2014			2013
Numerator:
Net loss		$	(98,846	)	$	(43,123	)	$	(27,857	)
Add: accretion of redeemable convertible preferred stock			—			(36	)		(34	)
Net loss attributable to common stockholders		$	(98,846	)	$	(43,159	)	$	(27,891	)
Denominator:
Weighted-average number of shares outstanding—basic and diluted			72,304			26,772			18,236
Net loss per share—basic and diluted		$	(1.37	)	$	(1.61	)	$	(1.53	)
The following potentially dilutive securities were excluded (as common stock equivalents) from the computation of diluted net loss per share for the periods presented as their effect would have been antidilutive (in thousands):
		As of January 31,
		2015			2014			2013
Shares subject to options to purchase common stock			12,360			16,329			12,019
Unvested restricted stock units			5,743			626			—
Unvested early exercised common shares			704			1,593			1,866
Employee stock purchase plan			320			—			—
Redeemable convertible preferred stock			—			—			38,868
Recent Accounting Pronouncements
In May 2014, the Financial Accounting Standards Board (FASB) released Accounting Standards Update (ASU) No. 2014-09, Revenue from Contracts with Customers, requiring an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The guidance in ASU No. 2014-09 supersedes the revenue recognition requirements in Accounting Standards Codification Topic 605, Revenue Recognition and permits the use of either the retrospective or cumulative effect transition method. The Company is required to adopt this standard starting in the first quarter of fiscal 2018. Early adoption is not permitted. The Company has not yet selected a transition method and is currently in the process of determining the impact of ASU No. 2014-09 on its consolidated financial statements and related disclosures.
In July 2013, the FASB released ASU No. 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists. The new standard requires that an unrecognized tax benefit should be presented as a reduction of a deferred tax asset for a net operating loss carryforward or other tax credit carryforward when settlement in this manner is available under the tax law. The Company adopted this accounting standard update on February 1, 2014 and the adoption did not have a significant impact on its consolidated financial position, results of operations, comprehensive loss or cash flows.
In February 2013, the FASB issued an accounting standard update to require reclassification adjustments from other comprehensive income to be presented either in the financial statements or in the notes to the financial statements. The Company adopted this accounting standard update on February 1, 2013 and the adoption did not have a significant impact on its consolidated financial position, results of operations, comprehensive loss or cash flows.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Jan. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements
	Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The standard describes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, to measure the fair value:
		•		Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities.
		•		Level 2—Inputs are quoted prices for similar assets and liabilities in active markets or inputs other than quoted prices that are observable for the assets or liabilities, either directly or indirectly through market corroboration, for substantially the full term of the financial instruments.
		•		Level 3—Inputs are unobservable inputs based on our own assumptions used to measure assets and liabilities at fair value. The inputs require significant management judgment or estimation.
	In November 2014, the Company entered into foreign currency forward contracts to minimize the short-term impact of foreign currency exchange rate fluctuations on cash and certain trade and inter-company receivables and payables. These instruments are marked to market through earnings every period and generally are one month in original maturity. These instruments are classified within level 2 of the fair value hierarchy. As of January 31, 2015, the fair value of foreign exchange forward contracts outstanding was a loss of $59,000. The Company’s derivative assets and derivative liabilities as of January 31, 2015 are as follows (in thousands):
			As of January 31, 2015
			Nominal		Fair
			Amount		Value
	Forward Contracts:
	Purchased		$	—	$	—
	Sold		$	17,324	$	(59	)

Balance_Sheet_Components

Balance Sheet Components	12 Months Ended
	Jan. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance Sheet Components	4. Balance Sheet Components
	Property and Equipment
	Property and equipment, net consisted of the following (in thousands):
		As of January 31,
		2015			2014
	Computer equipment	$	9,226		$	5,619
	Lab equipment		17,768			6,517
	Software		3,443			1,443
	Furniture and fixtures		3,287			2,069
	Leasehold improvements		14,461			8,377
	Construction in progress		1,223			694
	Demonstration equipment		1,256			770
	Total property and equipment		50,664			25,489
	Less: accumulated depreciation		(13,948	)		(5,280	)
	Total property and equipment, net	$	36,716		$	20,209
	Costs incurred in connection with the development of the Company’s software are accounted for as follows: all costs incurred in the preliminary project and post-implementation stages are expensed as incurred. Certain costs incurred in the application development stage of a new product or projects are capitalized if certain criteria are met. Such costs are depreciated on a straight-line basis over the estimated useful lives of the related assets, which was estimated to be three years. Maintenance and training costs are typically expensed as incurred.
	Depreciation expense related to property and equipment for the years ended January 31, 2015, 2014 and 2013 was $8.8 million, $4.2 million and $1.1 million, respectively.

Employee_Loans

Employee Loans	12 Months Ended
	Jan. 31, 2015
Postemployment Benefits [Abstract]
Employee Loans	5. Employee Loans
	During the years ended January 31, 2011 and 2012, the Company issued full recourse loans to two employees to facilitate the exercise of their stock options. The first of these loans was issued in December 2011 with a principal amount of $1.0 million and an interest rate of at 1.3% per annum. The loan was contractually due and payable in full in December 2020 or upon such earlier date that the Company files a registration statement related to an initial public offering. The second of these loans was issued in June 2012 with a principal amount of $439,000 and an interest of 2.3% per annum. The loan was contractually due and payable in full in June 2020 or upon such earlier date that the Company files a registration statement related to an initial public offering. The principal loan amount and the accrued interest were $1.6 million as of January 31, 2013, and were reported as a deduction from stockholders’ equity on the Company’s consolidated balance sheets. Both of these loans and related interest were repaid in full in August 2013.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Jan. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	6. Commitments and Contingencies
	Leases
	The Company leases its facilities under various noncancelable operating leases with fixed rental payments. Rent expense totaled $5.3 million, $3.1 million and $0.5 million for the years ended January 31, 2015, 2014 and 2013, respectively. Future minimum commitments under these operating leases as of January 31, 2015 were as follows (in thousands):
	Years ending January 31:
	2016	$	6,045
	2017		6,215
	2018		6,246
	2019		6,399
	2020		6,557
	Thereafter		11,541
		$	43,003
	In July 2014, the Company entered into a new facility lease agreement for its North Carolina office. The 84-month lease commenced on August 1, 2014 and provides 47,986 square feet of space. Total rent, including common area maintenance expense and fixed operating expense, payable over the lease period is $5.0 million. As part of the lease agreement, the Company will receive an allowance of $1.4 million for tenant improvements. This allowance was included in the calculation of rent expense and related deferred rent balances. As a condition of the lease agreement, the Company is required to maintain a letter of credit of $0.9 million, with the landlord named as the beneficiary. In December 2014, the Company amended the lease agreement for its North Carolina office which grants the Company access to an additional 38,909 square feet of space on February 1, 2016 through the same term as the original facility lease.
	In April 2013, the Company entered into a facility lease agreement. The 96-month lease commenced on November 1, 2013 and provides 164,608 square feet space in San Jose, California. Total rent, including operating expenses, payable over the lease period is $35.5 million. As part of the lease agreement, the Company received $4.9 million in tenant improvement allowance during the year ended January 31, 2014. This tenant improvement allowance was included in the calculation of rent expense and related deferred rent balances. As a condition of the lease agreement, the Company is required to maintain a letter of credit of $3.9 million, with the landlord named as the beneficiary. The Company has the option to extend the term of the lease for an additional period of 60 months.
	Contingencies
	From time to time, the Company is party to litigation and subject to claims that arise in the ordinary course of business, including actions with respect to employment claims and other matters. Although the results of litigation and claims are inherently unpredictable, the Company believes that the final outcome of such matters will not have a material adverse effect on the business, consolidated financial position, results of operations or cash flows.
	On October 29, 2013, NetApp, Inc. (NetApp) filed a lawsuit in United States District Court, Northern District of California, alleging violations of the federal Computer Fraud and Abuse Act (“CFAA”), trade secret misappropriation, unfair competition and related state law claims. The Company and three individuals, a sales engineer employee of an Australian affiliate, along with a sales representative and program manager of the Company, have been named as defendants. On January 10, 2014, NetApp filed a First Amended Complaint that added similar state law claims against three additional individuals as defendants. The First Amended Complaint alleges that the Australian defendant, a former employee of a NetApp reseller, accessed NetApp’s password-protected website allegedly restricted to NetApp partners, resellers, employees and customers, and downloaded confidential and proprietary information in violation of the Computer Fraud and Abuse Act. It further alleges that the other five individual defendants, who were formerly employed at NetApp, downloaded NetApp company documents and materials, including allegedly confidential and trade secret information and/or deleted NetApp documents and materials, prior to leaving NetApp. The complaint seeks unspecified damages and injunctive relief. The Company filed a response to the complaint on February 18, 2014. On May 12, 2014, the Court dismissed Nimble and all of the individual defendants except for the Australian defendant from the lawsuit. The court allowed NetApp to file an amended complaint concerning some of its claims, and NetApp filed a Second Amended Complaint on June 2, 2014. The Second Amended Complaint contains claims of alleged violations of the Computer Fraud and Abuse Act, unfair competition and related state law claims against the Company and the employee of an Australian affiliate of the Company. On January 29, 2015, the Court dismissed all claims for monetary damages against Nimble, including all claims based on the CFAA, with prejudice. The only remaining claim against Nimble is a narrowed claim of unfair competition under California and Professions Code Section 17200, which does not provide for monetary damages. The Court also dismissed, with prejudice, a portion of the CFAA claim, the trespass to chattel claim entirely, and a portion of the unfair competition claim against the Australian defendant. Following the Court’s order, the parties participated in a settlement conference on February 9, 2015 with the Court and were ordered to return on February 19, 2015 to continue discussing possible settlement of the federal lawsuit.
	On May 16, 2014, NetApp filed a lawsuit in the Superior Court of California, County of Santa Clara against the Company and the five individuals who were dismissed from the federal lawsuit, alleging claims that were similar to those dismissed from the federal lawsuit (i.e., that the individual defendants downloaded NetApp company documents and materials, including allegedly confidential and trade secret information and/or deleted NetApp documents and materials, prior to leaving NetApp). The state court complaint seeks unspecified damages and injunctive relief.
	On July 30, 2014, NetApp, the Company and the individual defendants participated in mediation of both lawsuits to work towards a mutually agreeable resolution to these cases, which was unsuccessful. The parties also participated in a settlement conference under the jurisdiction of the United States District Court, Northern District of California on February 9, 2015, February 19, 2015 and March 16, 2015. The parties entered into a written settlement agreement effective March 16, 2015, the terms of which are confidential. The settlement, which is not material to the Company’s consolidated financial statements, resolved all remaining claims in the two pending litigations. Dismissals with prejudice will be entered within five days of executing the settlement agreement.
	On January 23, 2015, one of the Company’s insurance carriers, Beazley Insurance Company, Inc., filed a lawsuit in the United States District Court for the Northern District of California, seeking a declaratory judgment and reimbursement against the Company, the individual defendants in the federal and state lawsuits with NetApp, and the Company’s other insurance carrier, National Union Fire Insurance Company of Pittsburg, PA. Through the lawsuit, Beazley is seeking a legal determination that it has no duty to defend or indemnify the defendants in the federal and state NetApp lawsuits, and that it is entitled to reimbursement of amounts paid under its insurance policy with the Company. The lawsuit has not yet been served and there has been no formal activity in the matter. The Company has agreed to voluntarily participate in a mediation currently scheduled for April 13, 2015 in an effort to resolve the insurance coverage dispute. A case management conference has been scheduled for May 21, 2015. No other activity has occurred in the case.
	Indemnification
	Some of the Company’s sales contracts require the Company to indemnify its customers against third-party claims asserting infringement of certain intellectual property rights, which may include patents, copyrights, trademarks, or trade secrets, and to pay judgments entered on such claims. The Company’s exposure under these indemnification provisions is generally limited to the total amount paid by the customer under the contract. However, certain contracts include indemnification provisions that could potentially expose the Company to losses in excess of the amount received under the contract. In addition, the Company indemnifies its officers, directors, and certain key employees while they are serving in good faith in their respective capacities. To date, there have been no claims under any indemnification provisions.
	Purchase Commitments
	The Company purchases components from a variety of suppliers and one contract manufacturer to provide manufacturing services for products. During the normal course of business, in order to manage manufacturing lead times and help ensure adequate component supply, the Company enters into agreements with its contract manufacturer and supplier that either allow them to procure inventory based upon criteria as defined by the Company or that establish the parameters defining the requirements. These agreements generally do not include any legally binding minimum commitment obligations. As of January 31, 2015, the Company had $22.7 million in several non-cancelable software license and service agreements for the internal use of software and services for vendor and customer relationship management, human resource, inventory forecasting application and communication and desktop applications and several operating commitments to fulfill inventory requirements arising from growing forecasts.

Common_Stock

Common Stock	12 Months Ended
	Jan. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Common Stock	7. Common Stock
	In December 2013, the Company completed its initial public offering of 9,200,000 shares of its common stock at a public offering price of $21.00 per share. Net cash proceeds from the initial public offering were approximately $175.4 million.
	In connection with the closing of the initial public offering, all of the shares of preferred stock outstanding automatically converted into an aggregate of 38.9 million shares of common stock.
	On December 18, 2013, the Company filed its Amended and Restated Certificate of Incorporation in connection with the closing of its initial public offering. Following the amendment, the Company had authorized capital stock of 755.0 million shares, comprising: (i) 750.0 million shares of common stock, par value $0.001 per share and (ii) 5.0 million shares of preferred stock, par value $0.001 per share.
	As of January 31, 2015, there were 750,000,000 shares of common stock authorized with a par value of $0.001 per share. The Company had reserved the following shares of authorized but unissued common stock:
		As of
		January 31,
		2015
	Issued and outstanding stock options		12,360,137
	Unvested restricted stock units		5,743,117
	Equity incentive plans		8,548,742
	Employee stock purchase plan		2,400,928
			29,052,924

Equity_Incentive_Plans

Equity Incentive Plans	12 Months Ended
	Jan. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Incentive Plans	8. Equity Incentive Plans
	Plan Descriptions
	2008 Equity Incentive Plan
	In May 2008, the Company adopted the 2008 Equity Incentive Plan (the 2008 Plan) for the benefit of its eligible employees, consultants, and independent directors. The 2008 Plan provides for the grant of stock awards, including incentive stock options, nonqualified stock options, restricted stock, stock appreciation rights and restricted stock units (RSUs). The Company grants stock options with an exercise price equal to the fair market value of its common stock on the date of the grant, as determined by the Board. The Company’s equity awards vest over a period of time as determined by the Board and expire no later than 10 years from the date of grant. Grants to new employees generally vest over a four-year period, at a rate of 25% one year from the date the optionee’s service period begins and 1/48 monthly thereafter. Subject to adjustment for certain changes in the Company’s capital structure, the maximum aggregate number of shares of common stock that may be issued under the 2008 Plan is 55,563,156.
	In December 2013, in connection with the closing of the Company’s initial public offering, the 2008 Plan was terminated and shares authorized for issuance under the 2008 Plan were cancelled (except for those shares reserved for issuance upon exercise of outstanding stock options). As of January 31, 2015, options to purchase and restricted stock units to convert to a total of 12,675,050 shares of common stock were outstanding under the 2008 Plan pursuant to their original terms and no shares were available for future grant.
	2013 Equity Incentive Plan
	In September 2013, the Company adopted the 2013 Equity Incentive Plan (the 2013 Plan), which became effective on December 12, 2013 and serves as the successor to the Company’s 2008 Plan. Upon completion of the Company’s initial public offering, the Company ceased granting awards under the 2008 Plan and any remaining shares available for issuance under the 2008 Plan were added to the shares reserved under the 2013 Plan. The 2013 Plan will terminate in September 2023, unless sooner terminated by the board of directors.
	The 2013 Plan provides for the grant of incentive stock options, non-statutory stock options, restricted stock awards, stock bonus awards, stock appreciation rights, RSUs and performance awards, all of which may be granted to eligible employees, consultants or directors.
	Under the terms of the 2013 Plan, awards may be granted at prices not less than 100% of the fair value of the Company’s common stock, as determined by the Company’s board of directors, on the date of grant for stock options. Options vest over a period of time as determined by the board of directors, generally over a four-year period, and expire ten years from date of grant.
	Initially, the aggregate number of shares of the Company’s common stock that may be issued pursuant to stock awards under the 2013 Plan after the 2013 Plan becomes effective is 10,168,504 shares, plus any reserved shares not issued or subject to outstanding grants under the 2008 Plan on the date the 2013 Plan became effective, shares that are subject to stock options or RSUs granted under the 2008 Plan that cease to be subject to such stock options or other awards by forfeiture or otherwise or are issued and later forfeited or repurchased by the Company after the date the 2013 Plan became effective, and shares that are subject to stock options or other awards under the 2008 Plan that are used to pay the exercise price of an option or withheld to satisfy the tax withholding obligations related to any award. The number of shares available for grant and issuance under the 2013 Plan will automatically increase on February 1st of each of the calendar years 2014 through 2022, by the lesser of (i) 5% of the number of shares issued and outstanding on each January 31st immediately prior to the date of increase or (ii) such number of shares determined by the Company’s board of directors. The maximum number of shares that may be issued pursuant to the exercise of incentive stock options under the 2013 Plan is 300 million shares. As of January 31, 2015, stock options to purchase and restricted stock units to convert to a total of 5,428,204 shares of common stock were outstanding under the 2013 Plan and 8,548,742 shares were reserved for future issuance.
	2013 Employee Stock Purchase Plan
	In September 2013, the Company adopted the 2013 Employee Stock Purchase Plan (the 2013 ESPP), which became effective on December 12, 2013.
	The 2013 ESPP initially authorizes the issuance of 2,015,299 shares of the Company’s common stock pursuant to purchase rights granted to eligible employees. The number of shares of common stock reserved for issuance will automatically increase on February 1st of each calendar year, by an amount equal to (i) 1% of the total number of outstanding shares of common stock and common stock equivalents on the immediately preceding January 31st, or (ii) such lesser number of shares of common stock as determined by the Company’s board of directors. The maximum number of shares that may be issued pursuant to the 2013 ESPP is 30 million shares. The 2013 ESPP is intended to qualify as an “employee stock purchase plan” within the meaning of Section 423 of the Code.
	The 2013 ESPP was implemented through a series of offerings of purchase rights to eligible employees. Except for the initial offering period, each offering period is for 24 months beginning March 10th and September 10th of each year, with each such offering period consisting of four six-month purchase periods. The initial offering period began December 12, 2013 and will end on March 9, 2016, with purchase dates on September 9, 2014, March 9, 2015, September 9, 2015 and March 9, 2016.
	Eligible employees may participate through payroll deductions of 1% to 15% of their earnings. Common stock will be issued to participating employees at a price per share equal to 85% of the lesser of (a) the fair market value on the offering date, or (b) the fair market value on the purchase date. In accordance with the 2013 ESPP, the fair market value of the Company’s common stock on the first day of the initial offering period was $21.00, the price per share at which shares were first sold to the public in the Company’s initial public offering, as specified in the Company’s final prospectus filed with the Securities and Exchange Commission on December 13, 2013 pursuant to Rule 424(b). As of January 31, 2015, the Company had 2,400,928 shares reserved for future issuance.
	Early Exercises of Stock Options
	Stock options granted under the 2008 Plan provide employee option holders, if approved by the Board, the right to exercise unvested options in exchange for restricted common stock, which is subject to a repurchase right held by the Company at the lower of (i) the fair market value of its common stock on the date of repurchase or (ii) the original purchase price. Early exercises of options are not deemed to be substantive exercises for accounting purposes and accordingly, amounts received for early exercises are recorded as a liability. As of January 31, 2015 and 2014, there were 704,226 and 1,593,298 shares, respectively, subject to repurchase related to stock options early exercised and unvested. These amounts are reclassified to common stock and additional paid-in capital as the underlying shares vest. As of January 31, 2015 and 2014, the Company recorded a liability related to these shares subject to repurchase in the amount of $2.1 million and $4.4 million, respectively, within other long-term liabilities in its consolidated balance sheets.
	During the year ended January 31, 2015, the Company repurchased 35,146 early exercised shares of outstanding common stock at a weighted-average price of $3.59 per share for an aggregate purchase price of $126,000. During the year ended January 31, 2014, the Company repurchased 125,035 early exercised shares of outstanding common stock at a weighted-average price of $1.75 per share for an aggregate purchase price of $219,000. During the year ended January 31, 2013, the Company repurchased 17,844 shares of outstanding common stock at a weighted-average price of $1.34 per share for an aggregate purchase price of $24,000. The common stock repurchased is removed from common stock outstanding, is not held in treasury stock and is available for reissuance.
	Fair Value of Common Stock
	Prior to the Company’s initial public offering, the Company’s board of directors considered numerous objective and subjective factors to determine the fair value of common stock at each grant date. These factors included, but were not limited to, (i) contemporaneous valuations of common stock performed by unrelated third-party firms; (ii) the prices for the preferred stock sold to outside investors; (iii) the rights, preferences and privileges of the preferred stock relative to the common stock; (iv) the lack of marketability of the Company’s common stock; (v) developments in the business; and (vi) the likelihood of achieving a liquidity event, such as an initial public offering or a merger or acquisition of the Company, given prevailing market conditions.
	The Company has used the publicly quoted price as the fair value of its common stock since its common stock became publicly traded in December 2013.
	Stock Options and RSUs
	The following is a summary of the Company’s stock option and RSU activity during the year ended January 31, 2015 (in thousands, except per-share amounts):
					Shares Subject to Options						Outstanding RSUs
					Outstanding
		Shares			Shares			Weighted-			Outstanding			Weighted-
		Available			Subject to			Average			RSUs			Average
		for Grant			Outstanding			Exercise						Grant
					Options			Price						Date Fair
														Value
	Balance as of January 31, 2014		10,142			16,329		$	2.99			626		$	18.81
	Additional options and RSUs authorized for issuance		3,583			—			N/A			—			N/A
	Options granted		(100	)		100			25.94			—			N/A
	Options exercised		—			(3,543	)		2.22			—			N/A
	Options canceled		526			(526	)		8.49			—			N/A
	Options repurchased		35			—			N/A			—			N/A
	RSUs granted		(5,988	)		—			N/A			5,988			31.3
	RSUs vested		—			—			N/A			(523	)		33.21
	RSUs canceled		348			—			N/A			(348	)		28.08
	RSUs withheld for tax		3			—			N/A			—			N/A
	Balance as of January 31, 2015		8,549			12,360		$	3.16			5,743		$	30.07
	The following table summarizes information about the Company’s stock options outstanding as of January 31, 2015 (in thousands, except per-share amounts):
		Shares Subject to Options Outstanding
		Number of			Weighted-			Weighted-			Aggregate
		Shares			Average			Average			Intrinsic Value
		Subject to			Exercise			Remaining
		Options			Price			Contractual
								Term
								(years)			(in thousands)
	Vested and expected to vest as of January 31, 2015		11,705		$	3.07			7.38		$	226,648
	Exercisable as of January 31, 2015		11,468			2.77			7.32			225,446
	The options exercisable as of January 31, 2015 included options that are exercisable prior to vesting. The intrinsic value of options vested and expected to vest and become exercisable as of January 31, 2015 was calculated based on the difference between the exercise price and the fair value of the Company’s common stock as of January 31, 2015. The intrinsic value of exercised options for the years ended January 31, 2015, 2014 and 2013 was $89.1 million, $10.0 million and $2.5 million, respectively, and was calculated based on the difference between the exercise price and the fair value of the Company’s common stock as of the exercise date.
	The fair value of stock options that vested in the years ended January 31, 2015, 2014 and 2013 was $11.4 million, $3.9 million and $2.4 million, respectively.
	Stock-Based Compensation
	The following table summarizes the components of stock-based compensation expense related to stock options, RSUs and ESPP (in thousands):
		Year Ended January 31,
		2015			2014			2013
	Cost of product revenue	$	1,508		$	232		$	48
	Cost of support and service revenue		2,380			468			114
	Research and development		15,137			3,049			874
	Sales and marketing		27,752			3,674			1,029
	General and administrative		10,290			1,726			539
	Total stock-based compensation expense	$	57,067		$	9,149		$	2,604
	The weighted-average fair value of options granted was $14.52, $3.94 and $1.33 per share for the years ended January 31, 2015, 2014 and 2013, respectively. The Company started to issue RSUs in the year ended January 31, 2014. The weighted-average fair value of RSUs granted was $31.30 and $18.92 per share for the years ended January 31, 2015 and 2014, respectively. The weighted average fair value of stock purchase rights granted was $7.20 and $6.91 per share for the year ended January 31, 2015 and 2014, respectively.
As of January 31, 2015, there was $18.8 million of unrecognized stock-based compensation expense for stock options that will be recognized over the remaining weighted-average period of 2.4 years. As of January 31, 2015, there was $154.5 million of unrecognized stock-based compensation expense for RSUs that will be recognized over the remaining weighted-average period of 3.4 years. As of January 31, 2015, there was $3.5 million of unrecognized stock-based compensation expense for stock purchase rights that will be recognized over the remaining offering period, through September 2016.
The Company estimated the fair value of employee stock options using a Black-Scholes-Merton option-valuation model with the following assumptions:
	Year Ended January 31,
	2015			2014			2013
Expected term (in years)		6			6			5.8
Volatility		59	%		62	%		62	%
Risk-free interest rate		1.8	%		0.8% - 2.0	%		0.6% - 3.6	%
Dividend yield		0	%		0	%		0	%
Expected Term.    Given the Company’s limited historical exercise behavior, the expected term of options granted was determined using the “simplified” method. Under this approach, the expected term is presumed to be the average of the vesting term and the contractual term of the option.
Expected Volatility.    Since the Company does not have sufficient trading history for its common stock, the expected volatility used is based on volatility of similar entities. In evaluating similarity, the Company considered factors such as industry, stage of life cycle, size, and financial leverage.
Risk-Free Interest Rate.    The risk-free rate that the Company uses is based on U.S. Treasury zero-coupon issues with remaining terms similar to the expected term of the options.
Dividend Yield.    The Company has never declared or paid any cash dividends and does not plan to pay cash dividends in the foreseeable future and, therefore, uses an expected dividend yield of zero in the valuation model.
The Company is required to estimate forfeitures at the time of grant and revise those estimates in subsequent periods if actual forfeitures differ from those estimates. The Company uses historical data to estimate pre-vesting option forfeitures and records stock-based compensation expense only for those awards that are expected to vest. All stock-based payment awards are amortized on a straight-line basis over the requisite service periods of the awards, which are generally the vesting periods.
The Company accounted for the stock purchase rights at the grant date (first day of the offering period) by valuing the four purchase periods separately. The value of the stock purchase right consists of: (1) 15% discount on the purchase of the stock and (2) 85% of the call option. The call option was valued using the Black-Scholes-Merton option-pricing model with the following assumptions:
	Year Ended January 31,
	2015			2014
Expected term (in years)		0.5 - 2.0			0.8 - 2.3
Volatility		32% - 47	%		43% - 48	%
Risk-free interest rate		0.1% - 0.6	%		0.1% - 0.4	%
Dividend yield		0	%		0	%

401k_Plan

401(k) Plan	12 Months Ended
	Jan. 31, 2015
Compensation and Retirement Disclosure [Abstract]
401(k) Plan	9. 401(k) Plan
	The Company has a qualified defined contribution plan under Section 401(k) of the Internal Revenue Code covering eligible employees. Participants may make pre-tax contributions to the plan from their eligible earnings up to the statutorily prescribed annual limit on pre-tax contributions under the Code. Although the plan provides for a discretionary employer matching contribution, to date the Company has not made such a contribution on behalf of employees.

Income_Taxes

Income Taxes	12 Months Ended
	Jan. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes
	The provision for income taxes is based upon the loss before provision for income taxes as follows (in thousands):
		Year Ended January 31,
		2015			2014			2013
	U.S. operations	$	(100,136	)	$	(44,007	)	$	(27,972	)
	Non-U.S. operations		2,127			1,309			214
		$	(98,009	)	$	(42,698	)	$	(27,758	)
	The Company’s provision for income taxes of $0.8 million for the year ended January 31, 2015 consisted of current foreign taxes, current state taxes and deferred foreign taxes. The Company’s provision for income taxes of $0.4 million for the year ended January 31, 2014 consisted of current foreign taxes, current federal taxes, current state taxes and deferred foreign taxes. The Company’s provision for income taxes of $0.1 million for the year ended January 31, 2013 consisted of current foreign taxes and current state taxes.
	The Company’s effective tax rate differs from the U.S. federal statutory tax rate due to the following (in thousands):
		Year Ended January 31,
		2015			2014			2013
	U.S. federal taxes at statutory tax rate	$	(33,323	)	$	(14,492	)	$	(9,438	)
	State taxes, net of federal benefit		(2,743	)		(1,414	)		(1,414	)
	Nondeductible expenses		396			218			187
	Nondeductible stock-based compensation		5,293			1,469			689
	Research and development credits		(2,739	)		(1,609	)		(855	)
	Change in valuation allowance		33,942			16,253			10,930
	Other		11			—			—
	Provision for income taxes	$	837		$	425		$	99
	The significant components of net deferred tax assets were as follows (in thousands):
		As of January 31,
		2015			2014
	Deferred tax assets:
	Net operating losses	$	42,696		$	25,379
	Depreciation		352			366
	Accruals and reserves		8,090			6,528
	Deferred revenue		6,748			2,285
	Stock-based compensation		9,197			1,174
	Research and development tax credits		6,427			3,600
	Gross deferred tax assets		73,510			39,332
	Depreciation and amortization		(11	)		—
	Net deferred tax assets prior to valuation allowance		73,499			39,332
	Valuation allowance		(73,235	)		(39,260	)
	Total net deferred tax assets	$	264		$	72
	The net valuation allowance increased by $34.0 million during the years ended January 31, 2015. Management has recorded a full valuation allowance against its net domestic deferred tax assets as it is not more likely than not that the assets will be realized based on the Company’s history of losses.
	As of January 31, 2015, the Company had net operating loss carryforwards and research and development credits as follows (in thousands):
		Amount			Expiration Year
	Net operating losses, federal	$	170,787		2028-2035
	Net operating losses, state		90,534		2028-2035
	Research and development credits, federal		5,689		2028-2035
	Research and development credits, California		5,749		2029 - Indefinite
	Research and development credits, North Carolina		74		2029 - Indefinite
	The Company uses the ‘with-and-without’ approach to determine the recognition and measurement of excess tax benefits. Accordingly, the Company has elected to recognize excess income tax benefits from stock option exercises in additional paid in capital only if an incremental income tax benefit would be realized after considering all other tax attributes presently available to the Company. As of January 31, 2015, the amount of such excess tax benefits from stock options included in net operating losses was $57.9 million and $9.7 million for federal and California purposes. In addition, the Company has elected to account for the indirect effects of stock-based awards on other tax attributes, such as the research and alternative minimum tax credits, through its statements of operations. Federal and California tax laws impose limitations on the utilization of net operating loss and credit carryforwards in the event of an “ownership change” for tax purposes, as defined in Section 382 of the Internal Revenue Code. The Company determined there was no “ownership change” as of January 31, 2015.
	The Company does not intend on remitting undistributed earnings of foreign subsidiaries and, accordingly, no deferred tax liability has been established relative to these earnings. As of January 31, 2015, the Company’s undistributed earnings of foreign subsidiaries were $2.4 million.
	The Company recognizes interest and penalties related to uncertain tax positions, if any, as a component of its income tax provision. The Company recognized de minimis interest and penalties related to uncertain tax positions for the years ended January 31, 2015, 2014 and 2013.
	A reconciliation of the beginning and ending balances of gross unrecognized tax benefits, before interest and penalties is as follows (in thousands):
		Amount
	Balance as of January 31, 2012	$	548
	Additions for tax positions related to prior year		0
	Additions for tax positions related to current year		535
	Reductions for tax positions related to prior year		0
	Balance as of January 31, 2013		1,083
	Additions for tax positions related to prior year		9
	Additions for tax positions related to current year		955
	Reductions for tax positions related to prior year		0
	Balance as of January 31, 2014		2,047
	Additions for tax positions related to prior year		153
	Additions for tax positions related to current year		1,594
	Reductions for tax positions related to prior year		(6	)
	Balance as of January 31, 2015	$	3,788
	The gross unrecognized tax benefits, if recognized, would affect the effective tax rate by approximately $39,000 as of January 31, 2015. While it is often difficult to predict the final outcome of any particular uncertain tax position, the Company does not believe it is reasonably possible that the total amount of unrecognized tax benefits as of January 31, 2015 will materially change in the next 12 months.
	The Company files federal, state, and foreign income tax returns in many jurisdictions in the United States and abroad. For U.S. federal and state income tax purposes, the statute of limitations currently remains open for all years due to the Company’s NOL carryforwards. The Company is not currently under examination in any jurisdiction.
	The Company recorded an income tax provision of $0.8 million for the year ended January 31, 2015. The income tax provision for the year ended January 31, 2015 reflected mainly income tax expense in non-U.S. jurisdictions. The Company continues to maintain a valuation allowance for its U.S. federal and state deferred tax assets.

Segments

Segments	12 Months Ended
	Jan. 31, 2015
Segment Reporting [Abstract]
Segments	11. Segments
	The Company’s chief operating decision maker is its chief executive officer. The chief executive officer reviews consolidated financial information accompanied by information about revenue by product line for purposes of allocating resources and evaluating financial performance. The Company has one business activity and there are no segment managers who are held accountable for operations, or operating results for levels or components. In addition, the majority of the Company’s operations and customers are located in the United States. As such, the Company has a single reporting segment and operating unit structure.
	Revenue by country or region, based on the mailing address of the customer, for the periods presented was as follows (in thousands):
		Year Ended January 31,
		2015		2014		2013
	North America	$	186,145	$	107,305	$	49,330
	EMEA		28,210		11,731		3,895
	APAC		13,303		6,550		573
	Other		15		147		42
	Total revenue	$	227,673	$	125,733	$	53,840
	Long-lived assets located in the following countries and regions as of each period end were as follows (in thousands):
		As of January 31,
		2015		2014
	North America	$	40,521	$	24,069
	Other		433		252
	Total long-lived assets	$	40,954	$	24,321

Line_of_Credit

Line of Credit	12 Months Ended
	Jan. 31, 2015
Debt Disclosure [Abstract]
Line of Credit	12. Line of Credit
	In October 2013, the Company entered into an agreement with Wells Fargo Bank, National Association (Wells Fargo) to provide a secured revolving credit facility (the Credit Facility) that allows the Company to borrow up to $15.0 million for general corporate purposes. There was a $0.9 million reduction of the available line related to the Letter of Credit issued in July 2014 for the Company’s new facility lease in North Carolina. As of January 31, 2015, the remaining Credit Facility available for borrowings was $14.1 million. Amounts outstanding under the Credit Facility will bear interest at Wells Fargo’s prime rate with accrued interest payable on a monthly basis. In addition, the Company is obligated to pay a commitment fee of 0.20% per annum on the unused portion of the Credit Facility, with such fee payable on a quarterly basis. As of January 31, 2015, the commitment fee was capitalized and being amortized on the Company’s consolidated balance sheet. The Credit Facility was renewed in September 2014 for an incremental two-year period and now expires in October 2016. Under the credit facility renewal, the Company granted to Wells Fargo a first priority lien in its accounts receivable and other corporate assets, agreed to not pledge its intellectual property to other parties and became subject to certain reporting and financial covenants, as follows: (1) maintain minimum tangible net worth, defined as the aggregate of total stockholders’ equity plus subordinated debt less any intangible assets and less any loans or advances to, or investments in, any related entities or individuals, of $135 million; and (2) maintain a monthly ratio of not less than 1.25 to 1.00, based on the aggregate of its cash and net accounts receivable divided by total current liabilities minus current deferred revenue. As of January 31, 2015, no amounts had been drawn against the Credit Facility.

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Jan. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (unaudited)	13. Selected Quarterly Financial Data (unaudited)
	The following tables set forth selected unaudited quarterly consolidated statements of operations data for each of the eight quarters in fiscal 2015 and 2014 (in thousands, except per share data):
		Quarter Ended
		April 30,			July 31,			October 31,			January 31,			April 30,			July 31,			October 31,			January 31,
		2013			2013			2013			2014			2014			2014			2014			2015
	Net revenues	$	22,124		$	28,478		$	33,411		$	41,720		$	46,547		$	53,761		$	59,096		$	68,269
	Gross profit		13,581			18,180			22,022			27,739			30,212			35,245			38,432			44,831
	Net loss		(9,371	)		(10,463	)		(10,136	)		(13,153	)		(19,595	)		(26,117	)		(28,389	)		(24,745	)
	Accretion of redeemable convertible preferred stock		(10	)		(11	)		(10	)		(5	)		—			—			—			—
	Net loss attributable to common stockholders	$	(9,381	)	$	(10,474	)	$	(10,146	)	$	(13,158	)	$	(19,595	)	$	(26,117	)	$	(28,389	)	$	(24,745	)
	Net loss per share attributable to common stockholders, basic and diluted	$	(0.47	)	$	(0.51	)	$	(0.48	)	$	(0.29	)	$	(0.28	)	$	(0.37	)	$	(0.39	)	$	(0.33	)

Description_of_Business_and_Ba1

Description of Business and Basis of Presentation (Policies)	12 Months Ended
	Jan. 31, 2015
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation
	The consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and include the consolidated accounts of the Company and its subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Such estimates include, but are not limited to, the determination of the best estimated selling prices of deliverables included in multiple-deliverable revenue arrangements; the allowance for doubtful accounts; provision for excess or obsolete inventory; the useful lives of property and equipment; the warranty reserve; and the fair value of the Company’s common stock and stock options issued. Actual results could differ from these estimates.
Concentrations	Concentrations
	The Company’s financial instruments that are exposed to concentrations of credit risk are primarily cash and cash equivalents and trade accounts receivable. Cash and cash equivalents are maintained primarily at one financial institution, and deposits may exceed the amount of insurance provided on such deposits. Risks associated with cash and cash equivalents are mitigated by banking with a creditworthy institution. The Company has not experienced any losses on its deposits of cash and cash equivalents.
	The Company performs ongoing credit evaluations of its customers’ financial condition whenever deemed necessary and generally does not require collateral. The Company maintains an allowance for doubtful accounts based upon the expected collectability of its accounts receivable, which takes into consideration specific customer creditworthiness and current economic trends. During the third and fourth quarters of the year ended January 31, 2014, the Company consolidated the majority of its North American sales to two distributors, and as a result, accounts receivable and revenue increased in concentration. The majority of previous value added resellers (VARs) are now purchasing from these two distributors. Of all the Company’s customers, which include direct end-customers, VARs and distributors, the following customers individually accounted for more than 10% of the Company’s accounts receivable and revenue at the end of and for each period presented:
			% of Accounts Receivable								% of Revenue
			As of January 31,								Year Ended January 31,
			2015			2014					2015			2014			2013
	Customer A			44	%		47	%				48	%		16	%		*
	Customer B			18	%		*					*			*			*
	Customer C			16	%		21	%				21	%		*			*
	Customer D			*			10	%				*			*			*
	Customer E			*			*					*			*			15	%
	*	Represents less than 10%.
	There are no concentrations of business transacted with a particular market that would severely impact the Company’s business in the near term. However, the Company currently relies on one key contract manufacturer and supplier to produce most of its products; any disruption or termination of these arrangements could materially adversely affect the Company’s operating results.
Foreign Currency Translation and Transactions	Foreign Currency Translation and Transactions
	The functional currency of each of the Company’s foreign subsidiaries is its respective local currency. The Company translates all monetary assets and liabilities denominated in foreign currencies into U.S. dollars using the exchange rates in effect at the balance sheet dates and other assets and liabilities using historical exchange rates. Revenue and expenses are translated at average exchange rates in effect during the year. Translation adjustments are recorded within accumulated other comprehensive income (loss), a separate component of stockholders’ equity.
	Foreign currency denominated transactions are initially recorded and re-measured at the end of each period using the applicable exchange rate in effect. Foreign currency re-measurement losses are recognized in other expense, net, in the consolidated statements of operations. Foreign currency re-measurement net losses recognized were $2.1 million, $149,000, and $26,000 for the years ended January 31, 2015, 2014, and 2013, respectively. For the year ended January 31, 2015, the $2.1 million net losses from foreign currency remeasurement included $0.7 million gains related to foreign currency forward contracts.
Fair Value	Fair Value
	The carrying value of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximates fair value.
Cash and Cash Equivalents	Cash and Cash Equivalents
	The Company considers all highly liquid investments with an original maturity of 90 days or less at the date of purchase to be cash equivalents. Cash and cash equivalents consist principally of cash accounts and investments in money market funds.
Restricted Cash	Restricted Cash
	As a condition of the Company’s headquarters facility lease agreement, the Company is required to maintain a letter of credit of $3.9 million, with the landlord named as the beneficiary. These restricted cash balance have been excluded from the Company’s cash and cash equivalents balance and are classified as restricted cash on the Company’s consolidated balance sheets. As of January 31, 2015 and 2014, the amount of restricted cash was $4.0 million and $3.9 million, respectively, and classified as non-current (see Note 6).
Accounts Receivable	Accounts Receivable
	Accounts receivable are recorded at the invoiced amounts and do not bear interest. The Company maintains an allowance for doubtful accounts for estimated losses inherent in its accounts receivable portfolio. An allowance for doubtful accounts is calculated based on the aging of the Company’s trade receivables, historical experience, and management judgment. The Company writes off trade receivables against the allowance when management determines a balance is uncollectible and no longer actively pursues collection of the receivable. As of January 31, 2015 and 2014, the allowance for doubtful accounts was $0 and $76,000, respectively.
Inventories	Inventories
	Inventories consist primarily of raw materials related to component parts, finished goods, which include both inventory held for sale and service inventory held at service depots in support of customer service agreements, and customer evaluation inventory.
	The following is a summary of the Company’s inventories by major category (in thousands):
			As of January 31,
			2015			2014
	Raw materials		$	2,383		$	679
	Finished goods			6,871			3,605
	Evaluation inventory			2,727			1,128
			$	11,981		$	5,412
	Inventory values are stated at the lower of cost (on a first-in, first-out method), or market value. A provision is recorded to adjust inventory to its estimated realizable value when inventory is determined to be in excess of anticipated demand or obsolete. In determining the provision, the Company also considers estimated recovery rates based on the nature of the inventory. Service inventory is written down to its net realizable value based upon the estimated loss of utility starting from the date the service inventory is placed in the service depots. Customer evaluation inventory is written down to its net realizable value based upon its estimated loss of utility, starting from 180 days after the unit is placed in the evaluation pool, which is the expected life of the finished goods in the evaluation pool.
	The Company recorded inventory recoveries of $101,000 and inventory provisions of $252,000 and $421,000 for the years ended January 31, 2015, 2014 and 2013, respectively.
Property and Equipment	Property and Equipment
	Property and equipment are stated at cost, net of accumulated depreciation. Demonstration units are not sold and are transferred from inventory at cost. Depreciation is computed using the straight-line method over the following estimated useful lives:
	Property and Equipment		Useful Life
	Computer equipment, lab equipment and software		3 years
	Furniture and fixtures		5 years
	Leasehold improvements		Shorter of estimated useful life or remaining lease term
	Demonstration equipment		2 years
	Repairs and maintenance are expensed as incurred.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets
	The Company evaluates events and changes in circumstances that could indicate carrying amounts of long-lived assets, including property and equipment, may not be recoverable. When such events or changes in circumstances occur, the Company assesses the recoverability of long-lived assets by determining whether or not the carrying value of such assets will be recovered through undiscounted expected future cash flows. If the total of the future undiscounted cash flows is less than the carrying amount of an asset, the Company records an impairment charge for the amount by which the carrying amount of the assets exceeds the fair value of the asset. Through January 31, 2015, the Company had not written down any of its long-lived assets as a result of impairment.
Warranties	Warranties
	The Company provides a standard one-year warranty for hardware components covering material defects in materials and workmanship. In addition, the Company provides a 90-day warranty on the embedded software in its products for non-conformance with documented specifications. The Company accrues for estimated warranty costs based upon historical experience, and periodically assesses the adequacy of its recorded warranty liability at the end of each period. These costs are expensed as incurred and included in cost of product revenue in the Company’s consolidated statements of operations. The Company records warranty liability in other current liabilities in its consolidated balance sheet.
	The table below summarizes the activity in the warranty accrual (in thousands):
			Year Ended January 31,
			2015			2014
	Beginning balance		$	537		$	275
	Warranty expense for new warranties issued			1,372			1,432
	Utilization of warranty obligation			(1,233	)		(1,181	)
	Changes in estimates for pre-existing warranties			(485	)		11
	Ending balance		$	191		$	537
Revenue Recognition	Revenue Recognition
	The Company generates revenue from sales of software-enabled storage products and related support. The Company’s software that is integrated on the storage products is more than incidental, and functions together with the storage product to deliver its essential functionality. The Company also offers an optional support plan (typically one to five years). The support plan includes automated support (Proactive Wellness), bug fixes, updates and upgrades to product firmware and the Company’s management platform, including InfoSight, telephone support and expedited delivery times for replacement hardware parts. While support is not contractually mandatory, substantially all products shipped have been purchased together with a support plan. The Company also periodically sells optional installation services with its products that are not essential to the functionality of the storage product.
	Substantially all of the Company’s customer arrangements contain multiple deliverables. As a result, the Company accounts for the revenue for these sales in accordance with Accounting Standards Codification (ASC) 605-25 Revenue Recognition – Multiple Element Arrangements. Arrangements are divided into separate units of accounting based on whether the delivered items have stand-alone value. In its typical customer arrangements, the Company considers the following to be separate units of accounting: the storage product (together with the integrated software), support services and installation services. The Company has determined that each unit of accounting has stand-alone value because they are sold separately by the Company or could be resold by a customer on a stand-alone basis. The Company allocates the total consideration to all deliverables based on its determination of the units of accounting and their relative selling prices.
	As the Company has not yet established vendor-specific objective evidence (VSOE) or identified third-party evidence of fair value for its storage product (together with the integrated software) and installation services, it uses the best estimate of the selling price (BESP) of each deliverable to allocate the total arrangement fee among the separate units of accounting. The Company’s process to determine its BESP for its products and services is based on qualitative and quantitative considerations of multiple factors, which primarily include historical stand-alone sales, margin objectives, and discount behavior. Additional considerations are given to factors such as customer demographics, competitive alternatives, anticipated sales volume, costs to manufacture products or provide services, pricing practices, and market conditions. During the second quarter of the year ended January 31, 2013, the Company established VSOE of fair value for support services based on stand-alone renewals offered to its customers. As a result, beginning in the second quarter of the year ended January 31, 2013, the Company allocated the fair value of consideration related to support services based on VSOE of fair value for its support services. Prior to this change, the Company allocated consideration related to support services based on BESP. The effect of the change from BESP to VSOE of fair value for support services did not have a material impact on the allocation of consideration.
	Revenue is recognized when all of the following criteria are met:
		•		Persuasive Evidence of an Arrangement Exists. The Company relies upon non-cancelable sales agreements and purchase orders to determine the existence of an arrangement.
		•		Delivery Has Occurred. The Company uses shipping documents to verify delivery.
		•		The Fee Is Fixed or Determinable. The Company assesses whether the fee is fixed or determinable based on the payment terms associated with the transaction.
		•		Collectability Is Reasonably Assured. The Company assesses collectability based on credit analysis and payment history.
	It is the Company’s practice to identify a direct customer or an end-customer from its VARs and distributors prior to shipment. In the majority of instances, products are shipped directly to the direct customer or the end-customers. For a certain end-customer orders, products are shipped to resellers, distributors and third-party systems integrators for various reasons including importing of products to non-U.S. countries and systems integration (e.g. SmartStack integrations) prior to shipment to the end-customer or the end-customer specified location. Assuming all other revenue recognition criteria have been met, the Company generally recognizes revenue upon shipment, as title and risk of loss are transferred at that time. For certain VARs and distributors, title and risk of loss is transferred upon delivery to the end-customer and revenue is recognized after delivery has been completed. The Company’s arrangements with VARs and distributors do not contain rights of return, subsequent price discounts, price protection or other allowances for shipments completed.
	The majority of the Company’s deferred revenue consists of the unrecognized portion of revenue from sales of its support and service contracts. The Company records amounts to be recognized during the twelve months following the balance sheet date in deferred revenue, current portion in the consolidated balance sheets, and the remainder in deferred revenue, non-current portion in the consolidated balance sheets. As of January 31, 2015, the weighted average remaining contract period related to non-current deferred revenue was approximately 2.2 years.
	In November 2014, the Company announced its Storage on Demand (SoD) service offering, for enterprises and service providers managing storage in cloud environments. Under this pay-as-you-go subscription model, customers are generally billed on a monthly basis based on the amount of data consumed during the month. The SoD service offering includes all support services such as InfoSight. Revenue is recognized as services are performed. SoD revenue is recognized in support and service revenue in the consolidated statements of operations.
Shipping Costs	Shipping Costs
	Shipping charges billed to customers are included in product revenue and the related shipping and handling costs are included in cost of revenue.
Research and Development	Research and Development
	Research and development expense consists of personnel costs, including stock-based compensation expense, for the Company’s research and development personnel and product development costs, including engineering services, development software and hardware tools, depreciation of capital equipment and facility costs. Research and development costs are expensed as incurred.
Advertising Costs	Advertising Costs
	Advertising costs are expensed as incurred and are included in sales and marketing expense. Advertising costs for the years ended January 31, 2015, 2014 and 2013 were $3.0 million, $1.2 million and $0.4 million, respectively.
Stock-Based Compensation	Stock-Based Compensation
	Prior to the Company’s initial public offering on December 13, 2013, the Company’s board of directors determined the fair value of its common stock using various valuation methodologies, including valuation analyses performed by third-party valuation firms. After the initial public offering, the Company used the publicly quoted price as the fair value of its common stock.
	The Company determines the fair value of its stock options and shares of common stock to be issued related to its employee stock purchase plan (ESPP) on the date of grant utilizing the Black-Scholes-Merton option-pricing model, and is impacted by the fair value of its common stock, as well as changes in assumptions regarding a number of highly complex and subjective variables. These variables include, but are not limited to, the expected common stock price volatility over the term of the option awards, the expected term of the awards, risk-free interest rates and expected dividend yield. The Company generally recognizes compensation expense for stock option grants and ESPP on a straight-line basis over the requisite service period, which is generally four years for stock options, and six months to two years for ESPP. Stock-based compensation expense recognized at fair value includes the impact of estimated forfeitures.
	Stock-based compensation cost for restricted stock units (RSUs) is measured based on the fair value of the underlying shares on the date of grant. The RSUs generally vest over the requisite service period. The fair value of RSUs is determined by the estimated fair value of the Company’s common stock at the time of grant. Stock-based compensation expense is recognized at fair value and includes the impact of estimated forfeitures.
Income Taxes	Income Taxes
	The Company accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using the enacted tax rates in effect for the years in which the temporary differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected to be realized.
Derivative Financial Instruments	Derivative Financial Instruments
	During the year ended January 31, 2015, the Company entered into foreign currency forward contracts to minimize the short-term impact of foreign currency exchange rate fluctuations on cash and certain trade and inter-company receivables and payables. These contracts reduce the exposure to fluctuations in foreign currency exchange rate movements as the gains and losses associated with foreign currency balances are offset with the gains and losses on the forward contracts. The Company does not enter into foreign currency forward contracts for trading or speculative purposes. These instruments are marked to market through earnings every period and generally are one month in original maturity. The net gain or loss from the settlement of these foreign currency forward contracts is recorded in other expense, net in the consolidated statements of operations.
Net Loss Per Share Attributable to Common Stockholders	Net Loss Per Share Attributable to Common Stockholders
	Prior to the Company’s initial public offering on December 13, 2013, the Company calculated its basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for companies with participating securities. The Company considers all series of its redeemable convertible preferred stock to be participating securities. In the event a dividend is declared or paid on the Company’s common stock, holders of redeemable convertible preferred stock are entitled to a proportionate share of such dividend in proportion to the holders of common stock on an as-if converted basis. Under the two-class method, basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period, less shares subject to repurchase. Net loss attributable to common stockholders is determined by allocating undistributed earnings between common and redeemable convertible preferred stockholders. The diluted net loss per share attributable to common stockholders is computed by giving effect to all potential dilutive common stock equivalents outstanding for the period. For purposes of this calculation, redeemable convertible preferred stock, options to purchase common stock, repurchasable shares from early exercised options, unvested RSUs and shares subject to ESPP withholding are considered common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as their effect is antidilutive. Under the two-class method, the net loss attributable to common stockholders is not allocated to the convertible redeemable preferred stock as the convertible redeemable preferred stock do not have a contractual obligation to share in the Company’s losses.
	On December 13, 2013, all shares of redeemable convertible preferred stocks were converted to common stock.
	The following table sets forth the computation of net loss per share (in thousands, except per share amounts):
			Year Ended January 31,
			2015			2014			2013
	Numerator:
	Net loss		$	(98,846	)	$	(43,123	)	$	(27,857	)
	Add: accretion of redeemable convertible preferred stock			—			(36	)		(34	)
	Net loss attributable to common stockholders		$	(98,846	)	$	(43,159	)	$	(27,891	)
	Denominator:
	Weighted-average number of shares outstanding—basic and diluted			72,304			26,772			18,236
	Net loss per share—basic and diluted		$	(1.37	)	$	(1.61	)	$	(1.53	)
	The following potentially dilutive securities were excluded (as common stock equivalents) from the computation of diluted net loss per share for the periods presented as their effect would have been antidilutive (in thousands):
			As of January 31,
			2015			2014			2013
	Shares subject to options to purchase common stock			12,360			16,329			12,019
	Unvested restricted stock units			5,743			626			—
	Unvested early exercised common shares			704			1,593			1,866
	Employee stock purchase plan			320			—			—
	Redeemable convertible preferred stock			—			—			38,868
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	In May 2014, the Financial Accounting Standards Board (FASB) released Accounting Standards Update (ASU) No. 2014-09, Revenue from Contracts with Customers, requiring an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The guidance in ASU No. 2014-09 supersedes the revenue recognition requirements in Accounting Standards Codification Topic 605, Revenue Recognition and permits the use of either the retrospective or cumulative effect transition method. The Company is required to adopt this standard starting in the first quarter of fiscal 2018. Early adoption is not permitted. The Company has not yet selected a transition method and is currently in the process of determining the impact of ASU No. 2014-09 on its consolidated financial statements and related disclosures.
	In July 2013, the FASB released ASU No. 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists. The new standard requires that an unrecognized tax benefit should be presented as a reduction of a deferred tax asset for a net operating loss carryforward or other tax credit carryforward when settlement in this manner is available under the tax law. The Company adopted this accounting standard update on February 1, 2014 and the adoption did not have a significant impact on its consolidated financial position, results of operations, comprehensive loss or cash flows.
	In February 2013, the FASB issued an accounting standard update to require reclassification adjustments from other comprehensive income to be presented either in the financial statements or in the notes to the financial statements. The Company adopted this accounting standard update on February 1, 2013 and the adoption did not have a significant impact on its consolidated financial position, results of operations, comprehensive loss or cash flows.
Fair Value Measurements	Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The standard describes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, to measure the fair value:
		•		Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities.
		•		Level 2—Inputs are quoted prices for similar assets and liabilities in active markets or inputs other than quoted prices that are observable for the assets or liabilities, either directly or indirectly through market corroboration, for substantially the full term of the financial instruments.
		•		Level 3—Inputs are unobservable inputs based on our own assumptions used to measure assets and liabilities at fair value. The inputs require significant management judgment or estimation.
Research, Development, and Computer Software	Costs incurred in connection with the development of the Company’s software are accounted for as follows: all costs incurred in the preliminary project and post-implementation stages are expensed as incurred. Certain costs incurred in the application development stage of a new product or projects are capitalized if certain criteria are met. Such costs are depreciated on a straight-line basis over the estimated useful lives of the related assets, which was estimated to be three years. Maintenance and training costs are typically expensed as incurred.
Commitments and Contingencies	From time to time, the Company is party to litigation and subject to claims that arise in the ordinary course of business, including actions with respect to employment claims and other matters. Although the results of litigation and claims are inherently unpredictable, the Company believes that the final outcome of such matters will not have a material adverse effect on the business, consolidated financial position, results of operations or cash flows.
Segment Reporting	The Company’s chief operating decision maker is its chief executive officer. The chief executive officer reviews consolidated financial information accompanied by information about revenue by product line for purposes of allocating resources and evaluating financial performance. The Company has one business activity and there are no segment managers who are held accountable for operations, or operating results for levels or components. In addition, the majority of the Company’s operations and customers are located in the United States. As such, the Company has a single reporting segment and operating unit structure.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Jan. 31, 2015
Accounting Policies [Abstract]
Percentage of Company's Accounts Receivable and Revenue	Of all the Company’s customers, which include direct end-customers, VARs and distributors, the following customers individually accounted for more than 10% of the Company’s accounts receivable and revenue at the end of and for each period presented:
			% of Accounts Receivable								% of Revenue
			As of January 31,								Year Ended January 31,
			2015			2014					2015			2014			2013
	Customer A			44	%		47	%				48	%		16	%		*
	Customer B			18	%		*					*			*			*
	Customer C			16	%		21	%				21	%		*			*
	Customer D			*			10	%				*			*			*
	Customer E			*			*					*			*			15	%
	*	Represents less than 10%.
Summary of Company's Inventories by Major Category	The following is a summary of the Company’s inventories by major category (in thousands):
			As of January 31,
			2015			2014
	Raw materials		$	2,383		$	679
	Finished goods			6,871			3,605
	Evaluation inventory			2,727			1,128
			$	11,981		$	5,412
Estimated Useful Lives of Property and Equipment	Depreciation is computed using the straight-line method over the following estimated useful lives:
	Property and Equipment		Useful Life
	Computer equipment, lab equipment and software		3 years
	Furniture and fixtures		5 years
	Leasehold improvements		Shorter of estimated useful life or remaining lease term
	Demonstration equipment		2 years
Summary of Activity in Warranty Accrual	The table below summarizes the activity in the warranty accrual (in thousands):
			Year Ended January 31,
			2015			2014
	Beginning balance		$	537		$	275
	Warranty expense for new warranties issued			1,372			1,432
	Utilization of warranty obligation			(1,233	)		(1,181	)
	Changes in estimates for pre-existing warranties			(485	)		11
	Ending balance		$	191		$	537
Computation of Net Loss Per Share	The following table sets forth the computation of net loss per share (in thousands, except per share amounts):
			Year Ended January 31,
			2015			2014			2013
	Numerator:
	Net loss		$	(98,846	)	$	(43,123	)	$	(27,857	)
	Add: accretion of redeemable convertible preferred stock			—			(36	)		(34	)
	Net loss attributable to common stockholders		$	(98,846	)	$	(43,159	)	$	(27,891	)
	Denominator:
	Weighted-average number of shares outstanding—basic and diluted			72,304			26,772			18,236
	Net loss per share—basic and diluted		$	(1.37	)	$	(1.61	)	$	(1.53	)
Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share	The following potentially dilutive securities were excluded (as common stock equivalents) from the computation of diluted net loss per share for the periods presented as their effect would have been antidilutive (in thousands):
			As of January 31,
			2015			2014			2013
	Shares subject to options to purchase common stock			12,360			16,329			12,019
	Unvested restricted stock units			5,743			626			—
	Unvested early exercised common shares			704			1,593			1,866
	Employee stock purchase plan			320			—			—
	Redeemable convertible preferred stock			—			—			38,868

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Jan. 31, 2015
Fair Value Disclosures [Abstract]
Schedule of Derivative Assets and Derivative Liabilities	The Company’s derivative assets and derivative liabilities as of January 31, 2015 are as follows (in thousands):
		As of January 31, 2015
		Nominal		Fair
		Amount		Value
	Forward Contracts:
	Purchased	$	—	$	—
	Sold	$	17,324	$	(59	)

Balance_Sheet_Components_Table

Balance Sheet Components (Tables)	12 Months Ended
	Jan. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands):
		As of January 31,
		2015			2014
	Computer equipment	$	9,226		$	5,619
	Lab equipment		17,768			6,517
	Software		3,443			1,443
	Furniture and fixtures		3,287			2,069
	Leasehold improvements		14,461			8,377
	Construction in progress		1,223			694
	Demonstration equipment		1,256			770
	Total property and equipment		50,664			25,489
	Less: accumulated depreciation		(13,948	)		(5,280	)
	Total property and equipment, net	$	36,716		$	20,209

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Jan. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Future Minimum Commitments Under Operating Leases	Future minimum commitments under these operating leases as of January 31, 2015 were as follows (in thousands):
	Years ending January 31:
	2016	$	6,045
	2017		6,215
	2018		6,246
	2019		6,399
	2020		6,557
	Thereafter		11,541
		$	43,003

Common_Stock_Tables

Common Stock (Tables)	12 Months Ended
	Jan. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Reserved Shares of Authorized but Unissued Common Stock	The Company had reserved the following shares of authorized but unissued common stock:
		As of
		January 31,
		2015
	Issued and outstanding stock options		12,360,137
	Unvested restricted stock units		5,743,117
	Equity incentive plans		8,548,742
	Employee stock purchase plan		2,400,928
			29,052,924

Equity_Incentive_Plans_Tables

Equity Incentive Plans (Tables)	12 Months Ended
	Jan. 31, 2015
Schedule of Stock Option and RSU Award Activity	The following is a summary of the Company’s stock option and RSU activity during the year ended January 31, 2015 (in thousands, except per-share amounts):
					Shares Subject to Options						Outstanding RSUs
					Outstanding
		Shares			Shares			Weighted-			Outstanding			Weighted-
		Available			Subject to			Average			RSUs			Average
		for Grant			Outstanding			Exercise						Grant
					Options			Price						Date Fair
														Value
	Balance as of January 31, 2014		10,142			16,329		$	2.99			626		$	18.81
	Additional options and RSUs authorized for issuance		3,583			—			N/A			—			N/A
	Options granted		(100	)		100			25.94			—			N/A
	Options exercised		—			(3,543	)		2.22			—			N/A
	Options canceled		526			(526	)		8.49			—			N/A
	Options repurchased		35			—			N/A			—			N/A
	RSUs granted		(5,988	)		—			N/A			5,988			31.3
	RSUs vested		—			—			N/A			(523	)		33.21
	RSUs canceled		348			—			N/A			(348	)		28.08
	RSUs withheld for tax		3			—			N/A			—			N/A
	Balance as of January 31, 2015		8,549			12,360		$	3.16			5,743		$	30.07
Schedule of Stock Options Outstanding	The following table summarizes information about the Company’s stock options outstanding as of January 31, 2015 (in thousands, except per-share amounts):
		Shares Subject to Options Outstanding
		Number of			Weighted-			Weighted-			Aggregate
		Shares			Average			Average			Intrinsic Value
		Subject to			Exercise			Remaining
		Options			Price			Contractual
								Term
								(years)			(in thousands)
	Vested and expected to vest as of January 31, 2015		11,705		$	3.07			7.38		$	226,648
	Exercisable as of January 31, 2015		11,468			2.77			7.32			225,446
Components of Stock-based Compensation Expense Related to Stock Options, RSUs and ESPP	The following table summarizes the components of stock-based compensation expense related to stock options, RSUs and ESPP (in thousands):
		Year Ended January 31,
		2015			2014			2013
	Cost of product revenue	$	1,508		$	232		$	48
	Cost of support and service revenue		2,380			468			114
	Research and development		15,137			3,049			874
	Sales and marketing		27,752			3,674			1,029
	General and administrative		10,290			1,726			539
	Total stock-based compensation expense	$	57,067		$	9,149		$	2,604
Employee Stock Options [Member]
Schedule of Estimated Fair Value Black-Scholes-Merton Option-Valuation Model	The Company estimated the fair value of employee stock options using a Black-Scholes-Merton option-valuation model with the following assumptions:
		Year Ended January 31,
		2015			2014			2013
	Expected term (in years)		6			6			5.8
	Volatility		59	%		62	%		62	%
	Risk-free interest rate		1.8	%		0.8% - 2.0	%		0.6% - 3.6	%
	Dividend yield		0	%		0	%		0	%
Stock Purchase Rights [Member]
Schedule of Call Option Valued Using Black-Scholes-Merton Option-Pricing Model	The call option was valued using the Black-Scholes-Merton option-pricing model with the following assumptions:
		Year Ended January 31,
		2015			2014
	Expected term (in years)		0.5 - 2.0			0.8 - 2.3
	Volatility		32% - 47	%		43% - 48	%
	Risk-free interest rate		0.1% - 0.6	%		0.1% - 0.4	%
	Dividend yield		0	%		0	%

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Jan. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Provision for income taxes	The provision for income taxes is based upon the loss before provision for income taxes as follows (in thousands):
		Year Ended January 31,
		2015			2014			2013
	U.S. operations	$	(100,136	)	$	(44,007	)	$	(27,972	)
	Non-U.S. operations		2,127			1,309			214
		$	(98,009	)	$	(42,698	)	$	(27,758	)
Schedule of Effective Tax Rate Differs from U.S. Federal Statutory Tax Rate	The Company’s effective tax rate differs from the U.S. federal statutory tax rate due to the following (in thousands):
		Year Ended January 31,
		2015			2014			2013
	U.S. federal taxes at statutory tax rate	$	(33,323	)	$	(14,492	)	$	(9,438	)
	State taxes, net of federal benefit		(2,743	)		(1,414	)		(1,414	)
	Nondeductible expenses		396			218			187
	Nondeductible stock-based compensation		5,293			1,469			689
	Research and development credits		(2,739	)		(1,609	)		(855	)
	Change in valuation allowance		33,942			16,253			10,930
	Other		11			—			—
	Provision for income taxes	$	837		$	425		$	99
Significant Components of Net Deferred Tax Assets	The significant components of net deferred tax assets were as follows (in thousands):
		As of January 31,
		2015			2014
	Deferred tax assets:
	Net operating losses	$	42,696		$	25,379
	Depreciation		352			366
	Accruals and reserves		8,090			6,528
	Deferred revenue		6,748			2,285
	Stock-based compensation		9,197			1,174
	Research and development tax credits		6,427			3,600
	Gross deferred tax assets		73,510			39,332
	Depreciation and amortization		(11	)		—
	Net deferred tax assets prior to valuation allowance		73,499			39,332
	Valuation allowance		(73,235	)		(39,260	)
	Total net deferred tax assets	$	264		$	72
Schedule of Net Operating Loss Carryforwards and Research and Development Credits	As of January 31, 2015, the Company had net operating loss carryforwards and research and development credits as follows (in thousands):
		Amount			Expiration Year
	Net operating losses, federal	$	170,787		2028-2035
	Net operating losses, state		90,534		2028-2035
	Research and development credits, federal		5,689		2028-2035
	Research and development credits, California		5,749		2029 - Indefinite
	Research and development credits, North Carolina		74		2029 - Indefinite
Reconciliation of Gross Unrecognized Tax Benefits Before Interest and Penalties	A reconciliation of the beginning and ending balances of gross unrecognized tax benefits, before interest and penalties is as follows (in thousands):
		Amount
	Balance as of January 31, 2012	$	548
	Additions for tax positions related to prior year		0
	Additions for tax positions related to current year		535
	Reductions for tax positions related to prior year		0
	Balance as of January 31, 2013		1,083
	Additions for tax positions related to prior year		9
	Additions for tax positions related to current year		955
	Reductions for tax positions related to prior year		0
	Balance as of January 31, 2014		2,047
	Additions for tax positions related to prior year		153
	Additions for tax positions related to current year		1,594
	Reductions for tax positions related to prior year		(6	)
	Balance as of January 31, 2015	$	3,788

Segments_Tables

Segments (Tables)	12 Months Ended
	Jan. 31, 2015
Segment Reporting [Abstract]
Schedule of Revenue by Country or Region	Revenue by country or region, based on the mailing address of the customer, for the periods presented was as follows (in thousands):
		Year Ended January 31,
		2015		2014		2013
	North America	$	186,145	$	107,305	$	49,330
	EMEA		28,210		11,731		3,895
	APAC		13,303		6,550		573
	Other		15		147		42
	Total revenue	$	227,673	$	125,733	$	53,840
Schedule of Long-lived Assets	Long-lived assets located in the following countries and regions as of each period end were as follows (in thousands):
		As of January 31,
		2015		2014
	North America	$	40,521	$	24,069
	Other		433		252
	Total long-lived assets	$	40,954	$	24,321

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Jan. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Summary of Selected Unaudited Quarterly Consolidated Statements of Operations	The following tables set forth selected unaudited quarterly consolidated statements of operations data for each of the eight quarters in fiscal 2015 and 2014 (in thousands, except per share data):
		Quarter Ended
		April 30,			July 31,			October 31,			January 31,			April 30,			July 31,			October 31,			January 31,
		2013			2013			2013			2014			2014			2014			2014			2015
	Net revenues	$	22,124		$	28,478		$	33,411		$	41,720		$	46,547		$	53,761		$	59,096		$	68,269
	Gross profit		13,581			18,180			22,022			27,739			30,212			35,245			38,432			44,831
	Net loss		(9,371	)		(10,463	)		(10,136	)		(13,153	)		(19,595	)		(26,117	)		(28,389	)		(24,745	)
	Accretion of redeemable convertible preferred stock		(10	)		(11	)		(10	)		(5	)		—			—			—			—
	Net loss attributable to common stockholders	$	(9,381	)	$	(10,474	)	$	(10,146	)	$	(13,158	)	$	(19,595	)	$	(26,117	)	$	(28,389	)	$	(24,745	)
	Net loss per share attributable to common stockholders, basic and diluted	$	(0.47	)	$	(0.51	)	$	(0.48	)	$	(0.29	)	$	(0.28	)	$	(0.37	)	$	(0.39	)	$	(0.33	)

Description_of_Business_and_Ba2

Description of Business and Basis of Presentation - Additional Information (Detail)	12 Months Ended
	Jan. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business entity, date of incorporation	2007-11
Business entity state of incorporation	State of Delaware

Summary_of_Significant_Account2

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Oct. 31, 2013	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013	Oct. 31, 2014
		Distributor	Distributor
Summary Of Significant Accounting Policies [Line Items]
Number of major distributors		2	2
Foreign currency re-measurement net losses				$2,100,000	$149,000	$26,000
Cash and cash equivalents maturity period				90 days
Restricted cash	3,983,000	3,900,000		3,983,000	3,900,000
Allowance for doubtful accounts	0	76,000		0	76,000
Inventory recoveries	101,000			101,000
Inventory provisions		252,000			252,000	421,000
Weighted average remaining contract period related to non-current deferred revenue	2 years 2 months 12 days
Advertising costs				3,000,000	1,200,000	400,000
Foreign currency forward contracts, maturity period				1 month
Foreign Currency Forward Contracts [Member]
Summary Of Significant Accounting Policies [Line Items]
Foreign currency re-measurement gains				700,000
Stock Options [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based compensation expense requisite service period	4 years
Minimum [Member] | Employee stock purchase plan [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based compensation expense requisite service period	6 months
Maximum [Member] | Employee stock purchase plan [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based compensation expense requisite service period	2 years
Letter of Credit [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$3,900,000			$3,900,000			$0
Hardware Components [Member]
Summary Of Significant Accounting Policies [Line Items]
Standard product warranty period				1 year
Embedded Software [Member]
Summary Of Significant Accounting Policies [Line Items]
Standard product warranty period				90 days

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Percentage of Company's Accounts Receivable and Revenue (Detail) (Customer Concentration Risk [Member])	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Accounts Receivable [Member] | Customer A [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	44.00%	47.00%
Accounts Receivable [Member] | Customer B [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	18.00%
Accounts Receivable [Member] | Customer C [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	16.00%	21.00%
Accounts Receivable [Member] | Customer D [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage		10.00%
Sales Revenue, Net [Member] | Customer A [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	48.00%	16.00%
Sales Revenue, Net [Member] | Customer C [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	21.00%
Sales Revenue, Net [Member] | Customer E [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage			15.00%

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Percentage of Company's Accounts Receivable and Revenue (Parenthetical) (Detail) (Customer Concentration Risk [Member])	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Customer A [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	44.00%	47.00%
Customer A [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	48.00%	16.00%
Customer B [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	18.00%
Customer C [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	16.00%	21.00%
Customer C [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	21.00%
Customer D [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage		10.00%
Customer E [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage			15.00%
Maximum [Member] | Customer A [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage			10.00%
Maximum [Member] | Customer B [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage		10.00%
Maximum [Member] | Customer B [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	10.00%	10.00%	10.00%
Maximum [Member] | Customer C [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage		10.00%	10.00%
Maximum [Member] | Customer D [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	10.00%
Maximum [Member] | Customer D [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	10.00%	10.00%	10.00%
Maximum [Member] | Customer E [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	10.00%	10.00%
Maximum [Member] | Customer E [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration risk, Percentage	10.00%	10.00%

Summary_of_Significant_Account5

Summary of Significant Accounting Policies - Summary of Company's Inventories by Major Category (Detail) (USD $)	Jan. 31, 2015	Jan. 31, 2014
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]
Raw materials	$2,383	$679
Finished goods	6,871	3,605
Evaluation inventory	2,727	1,128
Total	$11,981	$5,412

Summary_of_Significant_Account6

Summary of Significant Accounting Policies - Estimated Useful Lives Of Property and Equipment (Detail)	12 Months Ended
	Jan. 31, 2015
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life description	Shorter of estimated useful life or remaining lease term
Demonstration Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	2 years

Summary_of_Significant_Account7

Summary of Significant Accounting Policies - Summary of Activity in Warranty Accrual (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014
Guarantees [Abstract]
Warranty accrual, beginning balance	$537	$275
Warranty expense for new warranties issued	1,372	1,432
Utilization of warranty obligation	-1,233	-1,181
Changes in estimates for pre-existing warranties	-485	11
Warranty accrual, ending balance	$191	$537

Summary_of_Significant_Account8

Summary of Significant Accounting Policies - Computation of Net Loss Per Share (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Numerator:
Net loss	($24,745)	($28,389)	($26,117)	($19,595)	($13,153)	($10,136)	($10,463)	($9,371)	($98,846)	($43,123)	($27,857)
Add: accretion of redeemable convertible preferred stock	0	0	0	0	-5	-10	-11	-10	0	-36	-34
Net loss attributable to common stockholders	($24,745)	($28,389)	($26,117)	($19,595)	($13,158)	($10,146)	($10,474)	($9,381)	($98,846)	($43,159)	($27,891)
Denominator:
Weighted-average number of shares outstanding-basic and diluted									72,304	26,772	18,236
Net loss per share-basic and diluted	($0.33)	($0.39)	($0.37)	($0.28)	($0.29)	($0.48)	($0.51)	($0.47)	($1.37)	($1.61)	($1.53)

Summary_of_Significant_Account9

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Detail)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Redeemable Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per share	0	0	38,868
Employee Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per share	12,360	16,329	12,019
Unvested restricted stock units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per share	5,743	626	0
Unvested Early Exercised Common Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per share	704	1,593	1,866
Employee stock purchase plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per share	320	0	0

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	Jan. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Fair value of foreign exchange forward contracts outstanding	$59,000

Fair_Value_Measurements_Schedu

Fair Value Measurements - Schedule of Derivative Assets and Derivative Liabilities (Detail) (USD $)	Jan. 31, 2015
In Thousands, unless otherwise specified
Forward Contracts Purchased [Member]
Derivative [Line Items]
Nominal Amount	$0
Fair Value	0
Forward Contracts Sold [Member]
Derivative [Line Items]
Nominal Amount	17,324
Fair Value	($59)

Balance_Sheet_Components_Sched

Balance Sheet Components - Schedule of Property and Equipment, Net (Detail) (USD $)	Jan. 31, 2015	Jan. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Total property and equipment	$50,664	$25,489
Less: accumulated depreciation	-13,948	-5,280
Total property and equipment, net	36,716	20,209
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	9,226	5,619
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	17,768	6,517
Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	3,443	1,443
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	3,287	2,069
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	14,461	8,377
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,223	694
Demonstration Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$1,256	$770

Balance_Sheet_Components_Addit

Balance Sheet Components - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Property, Plant and Equipment [Line Items]
Depreciation expense related to property and equipment	$8,753	$4,177	$1,118
Software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment	3 years

Employee_Loans_Additional_Info

Employee Loans - Additional Information (Detail) (USD $)	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2013	Jan. 31, 2012
		Employees	Employees
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of employees to whom recourse loans issued		2	2
Principal loan amount and accrued interest		$1,600,000
Loan and related interest repayment period	2013-08
First Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount of loan issued to employees			1,000,000
Percentage of interest rate for loan issued to employees			1.30%
Loan repayable description	The loan was contractually due and payable in full in December 2020 or upon such earlier date that the Company files a registration statement related to an initial public offering
Second Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount of loan issued to employees		$439,000
Percentage of interest rate for loan issued to employees		2.30%
Loan repayable description	The loan was contractually due and payable in full in June 2020 or upon such earlier date that the Company files a registration statement related to an initial public offering

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended
In Millions, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013	Apr. 30, 2013	Dec. 31, 2014	Jul. 31, 2014
				sqft	sqft	sqft
Other Commitments [Line Items]
Rent expense	$5.30	$3.10	$0.50
Contractual obligation	22.7
Tenant improvement allowances received		4.9
San Jose California [Member]
Other Commitments [Line Items]
Area of the leased property				164,608
Contractual obligation				35.5
Operating lease collateral in the form of a letter of credit				3.9
Lease term optional extension period				60 months
Term of operating lease				96 months
Lease commencement date				1-Nov-13
North Carolina Office [Member]
Other Commitments [Line Items]
Area of the leased property						47,986
Additional area of leased property					38,909
Contractual obligation						5
Tenant improvement allowances received						1.4
Operating lease collateral in the form of a letter of credit						$0.90
Term of operating lease						84 months
Lease commencement date					1-Feb-16	1-Aug-14

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Minimum Commitments Under Operating Leases (Detail) (USD $)	Jan. 31, 2015
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2016	$6,045
2017	6,215
2018	6,246
2019	6,399
2020	6,557
Thereafter	11,541
Future minimum commitments under operating leases	$43,003

Common_Stock_Additional_Inform

Common Stock - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013	Dec. 18, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net cash proceeds from initial public offering	$175,400	($1,310)	$176,729	$0
Common stock, shares authorized		750,000,000	750,000,000
Common stock, par value		$0.00	$0.00
Preferred stock, shares authorized		5,000,000	5,000,000
Preferred stock, par value		$0.00	$0.00
Amendment [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized capital after amendment					755,000,000
Common stock, shares authorized					750,000,000
Common stock, par value					$0.00
Preferred stock, shares authorized					5,000,000
Preferred stock, par value					$0.00
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock outstanding converted into shares of common stock	38,900,000
Initial Public Offering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Initial public offering shares	9,200,000
Initial public offering price per share	$21
Initial Public Offering [Member] | Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Initial public offering shares			9,200,000

Common_Stock_Summary_of_Reserv

Common Stock - Summary of Reserved Shares of Authorized but Unissued Common Stock (Detail)	Jan. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for authorized but unissued common stock	29,052,924
Issued and outstanding stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for authorized but unissued common stock	12,360,137
Unvested restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for authorized but unissued common stock	5,743,117
Equity incentive plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for authorized but unissued common stock	8,548,742
Employee stock purchase plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for authorized but unissued common stock	2,400,928

Equity_Incentive_Plans_Additio

Equity Incentive Plans - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013	31-May-08	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares available for issuance	8,549,000	10,142,000
Total number of common stock outstanding	12,360,000	16,329,000
Shares available for future grant	2,400,928
Shares authorized	29,052,924
Employee stock purchase plan, description	Common stock will be issued to participating employees at a price per share equal to 85% of the lesser of (a) the fair market value on the offering date, or (b) the fair market value on the purchase date.
Number of shares subject to repurchase	704,226	1,593,298
Liability incurred on stock repurchase	$2,100,000	$4,400,000
Common stock repurchased, share	35,146	125,035	17,844
Common stock repurchased, Weighted average price per share	$3.59	$1.75	$1.34
Common stock repurchased, value	126,000	219,000	24,000
Intrinsic value of exercised options	89,100,000	10,000,000	2,500,000
Fair value of stock option vested	11,400,000	3,900,000	2,400,000
Weighted-average fair value, option granted	$14.52	$3.94	$1.33
Unrecognized stock based compensation expense, stock options	18,800,000
Unrecognized stock based compensation expense, period	2 years 4 months 24 days
Unrecognized stock based compensation expense, equity instruments other than options	3,500,000
Unrecognized stock based compensation expense, stock purchase rights, period	2016-09
Dividend yield	0.00%
Valuation of stock purchase right	The value of the stock purchase right consists of (1) 15% discount on the purchase of the stock and (2) 85% of the call option.
Discount on value of the stock purchase right	15.00%
Call Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount on value of the stock purchase right	85.00%
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value, equity instruments other than options granted	$31.30	$18.92
Unrecognized stock based compensation expense, period	3 years 4 months 24 days
Unrecognized stock based compensation expense, equity instruments other than options	$154,500,000
Stock Purchase Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value, equity instruments other than options granted	$7.20	$6.91
2008 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards and options expiration period				10 years
Share awards and options vesting period				4 years
Stock vesting percentage				25.00%
Share awards and options, vesting terms	Grants to new employees generally vest over a four-year period, at a rate of 25% one year from the date the optionee's service period begins and 1/48 monthly thereafter.
Maximum shares available for issuance				55,563,156
Termination of equity incentive plan	2013-12
Total number of common stock outstanding	12,675,050
Shares available for future grant	0
2013 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards and options expiration period					10 years
Share awards and options vesting period					4 years
Maximum shares available for issuance					300,000,000
Termination of equity incentive plan	2023-09
Total number of common stock outstanding	5,428,204
Shares available for future grant	8,548,742
Plan, effective date	12-Dec-13
Shares granted price, percentage					100.00%
Shares authorized					10,168,504
Plan modification, description	The number of shares available for grant and issuance under the 2013 Plan will automatically increase on February 1st of each of the calendar years 2014 through 2022, by the lesser of (i) 5% of the number of shares issued and outstanding on each January 31st immediately prior to the date of increase or (ii) such number of shares determined by the Company's board of directors.
2013 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares available for issuance					30,000,000
Plan, effective date	12-Dec-13
Shares granted price, percentage					85.00%
Shares authorized					2,015,299
Plan modification, description	The number of shares of common stock reserved for issuance will automatically increase on February 1st of each calendar year, by an amount equal to (i) 1% of the total number of outstanding shares of common stock and common stock equivalents on the immediately preceding January 31st, or (ii) such lesser number of shares of common stock as determined by the Company's board of directors.
Employee stock purchase plan, offering period, description	Except for the initial offering period, each offering period is for 24 months beginning March 10th and September 10th of each year, with each such offering period consisting of four six-month purchase periods. The initial offering period began December 12, 2013 and will end on March 9, 2016, with purchase dates on September 9, 2014, March 9, 2015, September 9, 2015 and March 9, 2016.
Initial offering period beginning	12-Dec-13
Initial offering period ending	9-Mar-16
Payroll deductions, minimum percentage					1.00%
Payroll deductions, maximum percentage					15.00%
2013 Employee Stock Purchase Plan [Member] | Initial Public Offering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Initial offering price per share					21

Equity_Incentive_Plans_Schedul

Equity Incentive Plans - Schedule of Stock Option and RSU Award Activity (Detail) (USD $)	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Shares Available for Grant, Beginning balance	10,142,000
Shares Available for Grant, Additional options and RSUs authorized for issuance	3,583,000
Shares Available for Grant, Options granted	-100,000
Shares Available for Grant, Options exercised	0
Shares Available for Grant, Options canceled	526,000
Shares Available for Grant, Options repurchased	35,000
Outstanding RSUs, RSUs granted	-5,988,000
Outstanding RSUs, RSUs vested	0
Outstanding RSUs, RSUs canceled	348,000
Shares Available for Grant, RSUs withheld for tax	3,000
Shares Available for Grant, Ending balance	8,549,000
Shares Subject to Outstanding Options, Beginning balance	16,329,000
Shares Subject to Outstanding Options, Options granted	100,000
Shares Subject to Outstanding Options, Options exercised	-3,543,000
Shares Subject to Outstanding Options, Options canceled	-526,000
Shares Subject to Outstanding Options, Options repurchased	0
Shares Subject to Outstanding Options, Ending balance	12,360,000
Weighted-Average Exercise Price, Beginning balance	$2.99
Weighted-Average Exercise Price, Options granted	$25.94
Weighted-Average Exercise Price, Options exercised	$2.22
Weighted-Average Exercise Price, Options canceled	$8.49
Weighted-Average Exercise Price, Ending balance	$3.16
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Outstanding RSUs, Beginning balance	626,000
Outstanding RSUs, RSUs granted	5,988,000
Outstanding RSUs, RSUs vested	-523,000
Outstanding RSUs, RSUs canceled	-348,000
Outstanding RSUs, Ending balance	5,743,000	626,000
Weighted-Average Grant Date Fair Value, Beginning balance	$18.81
Weighted-Average Grant Date Fair Value, RSUs granted	$31.30	$18.92
Weighted-Average Grant Date Fair Value, RSUs vested	$33.21
Weighted-Average Grant Date Fair Value, RSUs canceled	$28.08
Weighted-Average Grant Date Fair Value, Ending balance	$30.07	$18.81

Equity_Incentive_Plans_Schedul1

Equity Incentive Plans - Schedule of Stock Options Outstanding (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jan. 31, 2015
Compensation Related Costs [Abstract]
Number of Shares Subject to Options, Vested and expected to vest	11,705
Number of Shares Subject to Options, Exercisable	11,468
Weighted-Average Exercise Price, Vested and expected to vest	$3.07
Weighted-Average Exercise Price, Exercisable	$2.77
Weighted-Average Remaining Contractual Term (Years), Vested and expected to vest	7 years 4 months 17 days
Weighted-Average Remaining Contractual Term (Years), Exercisable	7 years 3 months 26 days
Aggregate Intrinsic Value, Vested and expected to vest	$226,648
Aggregate Intrinsic Value, Exercisable	$225,446

Equity_Incentive_Plans_Compone

Equity Incentive Plans - Components of Stock-based Compensation Expense Related to Stock Options, RSUs and ESPP (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$57,067	$9,149	$2,604
Cost of Product Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	1,508	232	48
Cost of Support and Service Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	2,380	468	114
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	15,137	3,049	874
Sales and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	27,752	3,674	1,029
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$10,290	$1,726	$539

Equity_Incentive_Plans_Schedul2

Equity Incentive Plans - Schedule of Estimated Fair Value Black-Scholes-Merton Option-Valuation Model - Employee Stock Options (Detail)	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 years	6 years	5 years 9 months 18 days
Volatility	59.00%	62.00%	62.00%
Risk-free interest rate	1.80%
Risk-free interest rate, minimum		0.80%	0.60%
Risk-free interest rate, maximum		2.00%	3.60%
Dividend yield	0.00%	0.00%	0.00%

Equity_Incentive_Plans_Schedul3

Equity Incentive Plans - Schedule of Call Option Valued Using Black-Scholes-Merton Option-Pricing Model - Stock Purchase Rights (Detail)	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%
Stock Purchase Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility, minimum	32.00%	43.00%
Volatility, maximum	47.00%	48.00%
Risk-free interest rate, minimum	0.10%	0.10%
Risk-free interest rate, maximum	0.60%	0.40%
Dividend yield	0.00%	0.00%
Stock Purchase Rights [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 months	9 months 18 days
Stock Purchase Rights [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	2 years	2 years 3 months 18 days

401_k_Plan_Additional_Informat

401 (k) Plan - Additional Information (Detail) (USD $)	12 Months Ended
	Jan. 31, 2015
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Discretionary employer matching contribution on behalf of employees	$0

Income_Taxes_Schedule_of_Provi

Income Taxes - Schedule of Provision for income taxes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Income Tax Disclosure [Abstract]
U.S. operations	($100,136)	($44,007)	($27,972)
Non-U.S. operations	2,127	1,309	214
Loss before provision for income taxes	($98,009)	($42,698)	($27,758)

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Income Tax Contingency [Line Items]
Provision for income taxes	$837,000	$425,000	$99,000
Changes in valuation allowance	34,000,000
Percentage of ownership change	0.00%
Deferred tax liability	0
Undistributed earnings of foreign subsidiaries	2,400,000
Effect of unrecognized tax benefits on effective tax rate	39,000
Federal [Member]
Income Tax Contingency [Line Items]
Tax benefits from stock options	57,900,000
California [Member]
Income Tax Contingency [Line Items]
Tax benefits from stock options	$9,700,000

Income_Taxes_Schedule_of_Effec

Income Taxes - Schedule of Effective Tax Rate Differs from U.S. Federal Statutory Tax Rate (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Effective Income Tax Rate Reconciliation, Amount [Abstract]
U.S. federal taxes at statutory tax rate	($33,323)	($14,492)	($9,438)
State taxes, net of federal benefit	-2,743	-1,414	-1,414
Nondeductible expenses	396	218	187
Nondeductible stock-based compensation	5,293	1,469	689
Research and development credits	-2,739	-1,609	-855
Change in valuation allowance	33,942	16,253	10,930
Other	11	0	0
Provision for income taxes	$837	$425	$99

Income_Taxes_Significant_Compo

Income Taxes - Significant Components of Net Deferred Tax Assets (Detail) (USD $)	Jan. 31, 2015	Jan. 31, 2014
In Thousands, unless otherwise specified
Deferred tax assets:
Net operating losses	$42,696	$25,379
Depreciation	352	366
Accruals and reserves	8,090	6,528
Deferred revenue	6,748	2,285
Stock-based compensation	9,197	1,174
Research and development tax credits	6,427	3,600
Gross deferred tax assets	73,510	39,332
Depreciation and amortization	-11	0
Net deferred tax assets prior to valuation allowance	73,499	39,332
Valuation allowance	-73,235	-39,260
Total net deferred tax assets	$264	$72

Income_Taxes_Schedule_of_Net_O

Income Taxes - Schedule of Net Operating Loss Carryforwards and Research and Development Credits (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014
Income Tax Contingency [Line Items]
Research and development credits, Amount	6,427	$3,600
California [Member]
Income Tax Contingency [Line Items]
Research and development credits, Amount	5,749
North Carolina [Member]
Income Tax Contingency [Line Items]
Research and development credits, Amount	74
Minimum [Member] | California [Member]
Income Tax Contingency [Line Items]
Research and development credits, Expiry year	2029
Minimum [Member] | North Carolina [Member]
Income Tax Contingency [Line Items]
Research and development credits, Expiry year	2029
Maximum [Member] | California [Member]
Income Tax Contingency [Line Items]
Research and development credits, Expiry year	Indefinite
Maximum [Member] | North Carolina [Member]
Income Tax Contingency [Line Items]
Research and development credits, Expiry year	Indefinite
Federal [Member]
Income Tax Contingency [Line Items]
Net operating losses, Amount	170,787
Research and development credits, Amount	5,689
Federal [Member] | Minimum [Member]
Income Tax Contingency [Line Items]
Net operating losses, Expiry year	2028
Research and development credits, Expiry year	2028
Federal [Member] | Maximum [Member]
Income Tax Contingency [Line Items]
Net operating losses, Expiry year	2035
Research and development credits, Expiry year	2035
State [Member]
Income Tax Contingency [Line Items]
Net operating losses, Amount	90,534
State [Member] | Minimum [Member]
Income Tax Contingency [Line Items]
Net operating losses, Expiry year	2028
State [Member] | Maximum [Member]
Income Tax Contingency [Line Items]
Net operating losses, Expiry year	2035

Income_Taxes_Reconciliation_of

Income Taxes - Reconciliation of Gross Unrecognized Tax Benefits Before Interest and Penalties (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense [Abstract]
Beginning Balance	$2,047	$1,083	$548
Additions for tax positions related to prior year	153	9	0
Additions for tax positions related to current year	1,594	955	535
Reductions for tax positions related to prior year	-6	0	0
Ending Balance	$3,788	$2,047	$1,083

Segments_Additional_Informatio

Segments - Additional Information (Detail)	12 Months Ended
	Jan. 31, 2015
	Segment
Segment Reporting [Abstract]
Number of business activity	1

Segments_Schedule_of_Revenue_b

Segments - Schedule of Revenue by Country or Region (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$68,269	$59,096	$53,761	$46,547	$41,720	$33,411	$28,478	$22,124	$227,673	$125,733	$53,840
North America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									186,145	107,305	49,330
EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									28,210	11,731	3,895
APAC [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									13,303	6,550	573
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									$15	$147	$42

Segments_Schedule_of_Longlived

Segments - Schedule of Long-lived Assets (Detail) (USD $)	Jan. 31, 2015	Jan. 31, 2014
In Thousands, unless otherwise specified
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived assets	$40,954	$24,321
North America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived assets	40,521	24,069
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived assets	$433	$252

Line_of_Credit_Additional_Info

Line of Credit - Additional Information (Detail) (USD $)	1 Months Ended		9 Months Ended	12 Months Ended
	Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
Line of Credit Facility [Line Items]
Line of credit facility unused portion commitment fee		0.20%
Line of credit facility renewal date			2014-09
Line of credit facility incremental period			2 years
Line of credit facility expiration date			2016-10
Line of credit facility financial covenants				(1) maintain minimum tangible net worth, defined as the aggregate of total stockholders' equity plus subordinated debt less any intangible assets and less any loans or advances to, or investments in, any related entities or individuals, of $135 million; and (2) maintain a monthly ratio of not less than 1.25 to 1.00, based on the aggregate of its cash and net accounts receivable divided by total current liabilities minus current deferred revenue.
Minimum tangible net worth limit	$135,000,000		$135,000,000
Credit Facility, current amount outstanding				3,983,000	3,900,000
Reduction of available line related to Letter of Credit issued	-900,000
Remaining Credit Facility available for borrowings	14,100,000		14,100,000
Wells Fargo Bank, National Association [Member]
Line of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity		15,000,000
Letter of Credit [Member]
Line of Credit Facility [Line Items]
Credit Facility, current amount outstanding	$0		$0	$3,900,000

Selected_Quarterly_Financial_D2

Selected Quarterly Financial Data (unaudited) (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Net revenues	$68,269	$59,096	$53,761	$46,547	$41,720	$33,411	$28,478	$22,124	$227,673	$125,733	$53,840
Gross profit	44,831	38,432	35,245	30,212	27,739	22,022	18,180	13,581	148,720	81,522	33,390
Net loss	-24,745	-28,389	-26,117	-19,595	-13,153	-10,136	-10,463	-9,371	-98,846	-43,123	-27,857
Accretion of redeemable convertible preferred stock	0	0	0	0	-5	-10	-11	-10	0	-36	-34
Net loss attributable to common stockholders	($24,745)	($28,389)	($26,117)	($19,595)	($13,158)	($10,146)	($10,474)	($9,381)	($98,846)	($43,159)	($27,891)
Net loss per share attributable to common stockholders, basic and diluted	($0.33)	($0.39)	($0.37)	($0.28)	($0.29)	($0.48)	($0.51)	($0.47)	($1.37)	($1.61)	($1.53)