Workday (WDAY) 10-Q 5 Sep 18 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares shares in Millions	6 Months Ended
	Jul. 31, 2018	Aug. 31, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	Workday, Inc.
Entity Central Index Key	1,327,811
Current Fiscal Year End Date	--01-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jul. 31, 2018
Document Fiscal Year Focus	2,019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Trading Symbol	WDAY
Entity Common Stock, Shares Outstanding		217

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Current assets:
Cash and cash equivalents	$ 1,693,743	$ 1,134,355
Marketable securities	1,291,352	2,133,495
Trade and other receivables, net	457,496	528,208
Deferred costs	66,274	63,060
Prepaid expenses and other current assets	105,173	97,860
Total current assets	3,614,038	3,956,978
Property and equipment, net	678,525	546,609
Deferred costs, noncurrent	140,423	140,509
Acquisition-related intangible assets, net	35,927	34,234
Goodwill	175,073	159,376
Other assets	121,074	109,718
Total assets	4,765,060	4,947,424
Current liabilities:
Accounts payable	32,910	20,998
Accrued expenses and other current liabilities	119,972	121,879
Accrued compensation	140,340	148,247
Unearned revenue	1,393,848	1,426,241
Current portion of convertible senior notes, net	226,877	341,509
Total current liabilities	1,913,947	2,058,874
Convertible senior notes, net	950,132	1,149,845
Unearned revenue, noncurrent	89,376	110,906
Other liabilities	36,381	47,434
Total liabilities	2,989,836	3,367,059
Stockholders’ equity:
Common stock	218	211
Additional paid-in capital	3,869,111	3,354,423
Treasury stock	(193,679)	0
Accumulated other comprehensive income (loss)	(12,431)	(46,413)
Accumulated deficit	(1,887,995)	(1,727,856)
Total stockholders’ equity	1,775,224	1,580,365
Total liabilities and stockholders’ equity	$ 4,765,060	$ 4,947,424

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Revenues:
Total revenues		$ 671,720	$ 525,320	$ 1,290,363	$ 1,005,181
Costs and expenses:
Product development	[1]	292,840	221,103	556,424	417,542
Sales and marketing	[1]	202,464	171,952	395,235	327,661
General and administrative	[1]	65,168	55,699	120,749	106,901
Total costs and expenses		760,702	606,949	1,450,609	1,147,010
Operating loss		(88,982)	(81,629)	(160,246)	(141,829)
Other income (expense), net		1,613	938	(2,235)	(725)
Loss before provision for (benefit from) income taxes		(87,369)	(80,691)	(162,481)	(142,554)
Provision for (benefit from) income taxes		(1,213)	1,841	(1,915)	4,022
Net loss		$ (86,156)	$ (82,532)	$ (160,566)	$ (146,576)
Net loss per share, basic and diluted (in dollars per share)		$ (0.40)	$ (0.40)	$ (0.75)	$ (0.71)
Weighted-average shares used to compute net loss per share, basic and diluted (in shares)		215,932	207,028	214,517	205,453
Subscription services
Revenues:
Total revenues		$ 565,659	$ 434,527	$ 1,087,808	$ 834,263
Costs and expenses:
Cost of goods and services sold	[1]	87,523	65,931	167,768	125,729
Professional services
Revenues:
Total revenues		106,061	90,793	202,555	170,918
Costs and expenses:
Cost of goods and services sold	[1]	$ 112,707	$ 92,264	$ 210,433	$ 169,177
[1]	(1) Costs and expenses include share-based compensation expenses as follows: Costs of subscription services$8,521 $6,580 $16,398 $12,271Costs of professional services12,518 9,301 23,310 17,322Product development75,354 56,923 143,865 107,952Sales and marketing29,367 25,942 54,979 49,101General and administrative21,303 22,777 41,170 42,665

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Costs of subscription services
Share-based compensation expense	$ 8,521	$ 6,580	$ 16,398	$ 12,271
Costs of professional services
Share-based compensation expense	12,518	9,301	23,310	17,322
Product development
Share-based compensation expense	75,354	56,923	143,865	107,952
Sales and marketing
Share-based compensation expense	29,367	25,942	54,979	49,101
General and administrative
Share-based compensation expense	$ 21,303	$ 22,777	$ 41,170	$ 42,665

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (86,156)	$ (82,532)	$ (160,566)	$ (146,576)
Other comprehensive income (loss), net of tax:
Net change in foreign currency translation adjustment	(474)	1,243	(1,261)	966
Net change in unrealized gains (losses) on available-for-sale debt securities, net of tax provision of $284, $0, $284, and $0, respectively	1,439	146	906	(629)
Net change in market value of effective foreign currency forward exchange contracts, net of tax provision of $2,481, $0, $4,905, and $0, respectively	17,370	(23,396)	34,337	(24,605)
Other comprehensive income (loss), net of tax	18,335	(22,007)	33,982	(24,268)
Comprehensive loss	$ (67,821)	$ (104,539)	$ (126,584)	$ (170,844)

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax, Portion Attributable to Parent	$ 284	$ 0	$ 284	$ 0
Foreign currency forward exchange contracts, tax	$ 2,481	$ 0	$ 4,905	$ 0

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Cash flows from operating activities
Net loss	$ (86,156)	$ (82,532)	$ (160,566)	$ (146,576)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	42,226	33,501	80,890	65,298
Share-based compensation expenses	147,063	121,523	279,722	229,311
Amortization of deferred costs	17,061	14,009	33,421	27,646
Amortization of debt discount and issuance costs	17,490	6,785	35,629	13,735
Other	(4,894)	1,927	(14,183)	6,185
Changes in operating assets and liabilities, net of business combinations:
Trade and other receivables, net	(104,758)	(71,422)	63,944	40,393
Deferred costs	(23,943)	(19,437)	(36,549)	(30,818)
Prepaid expenses and other assets	(5,446)	(8,968)	3,042	(12,018)
Accounts payable	5,987	10,778	13,941	10,213
Accrued expenses and other liabilities	(15,182)	(13,472)	(3,555)	(9,383)
Unearned revenue	68,168	22,434	(53,887)	1,162
Net cash provided by (used in) operating activities	57,616	15,126	241,849	195,148
Cash flows from investing activities
Purchases of marketable securities	(526,216)	(285,197)	(1,434,342)	(898,448)
Maturities of marketable securities	655,205	371,471	1,341,881	813,341
Sales of marketable securities	914,938	180,863	942,297	189,937
Owned real estate projects	(49,537)	(22,996)	(88,770)	(52,535)
Capital expenditures, excluding owned real estate projects	(53,346)	(38,528)	(102,208)	(69,121)
Business combinations, net of cash acquired	(26,737)	0	(26,737)	0
Purchase of other intangible assets	(1,000)	0	(1,000)	0
Purchases of non-marketable equity and other investments	(1,000)	(5,000)	(3,400)	(5,450)
Sale and maturities of non-marketable equity and other investments	0	732	0	732
Net cash provided by (used in) investing activities	912,307	201,345	627,721	(21,544)
Cash flows from financing activities
Payments on convertible senior notes	(350,005)	0	(350,005)	0
Proceeds from issuance of common stock from employee equity plans	38,686	32,274	41,297	34,527
Other	(59)	(32)	(116)	(76)
Net cash provided by (used in) financing activities	(311,378)	32,242	(308,824)	34,451
Effect of exchange rate changes	(162)	715	(582)	583
Net increase (decrease) in cash, cash equivalents, and restricted cash	658,383	249,428	560,164	208,638
Cash, cash equivalents, and restricted cash at the beginning of period	1,037,435	501,104	1,135,654	541,894
Cash, cash equivalents, and restricted cash at the end of period	1,695,818	750,532	1,695,818	750,532
Supplemental cash flow data
Cash paid for interest, net of amounts capitalized	14	46	33	46
Cash paid for income taxes	1,492	1,262	3,206	2,608
Non-cash investing and financing activities:
Vesting of early exercised stock options	0	282	0	564
Purchases of property and equipment, accrued but not paid	63,052	33,219	63,052	33,219
Non-cash additions to property and equipment	$ 307	$ 485	$ 365	$ 627

Condensed Consolidated Stateme8

Condensed Consolidated Statements of Cash Flows (Reconciliation) - USD ($) $ in Thousands	Jul. 31, 2018	Jul. 31, 2017
Reconciliation of cash, cash equivalents, and restricted cash as shown in the statements of cash flows
Cash and cash equivalents	$ 1,693,743	$ 748,599
Restricted cash included in Other assets	2,075	1,933
Total cash, cash equivalents, and restricted cash	$ 1,695,818	$ 750,532

Overview and Basis of Presentat

Overview and Basis of Presentation	6 Months Ended
	Jul. 31, 2018
Accounting Policies [Abstract]
Overview and Basis of Presentation	Overview and Basis of Presentation Company and Background Workday provides financial management, human capital management, and analytics applications designed for the world's largest companies, educational institutions, and government agencies. We offer innovative and adaptable technology focused on the consumer internet experience and cloud delivery model. Our applications are designed for global enterprises to manage complex and dynamic operating environments. We provide our customers highly adaptable, accessible, and reliable applications to manage critical business functions that enable them to optimize their financial and human capital resources. We were originally incorporated in March 2005 in Nevada and in June 2012, we reincorporated in Delaware. As used in this report, the terms "Workday," "registrant," "we," "us," and "our" mean Workday, Inc. and its subsidiaries unless the context indicates otherwise. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States ("GAAP") and applicable rules and regulations of the Securities and Exchange Commission ("SEC") regarding interim financial reporting. The condensed consolidated financial statements include the results of Workday, Inc. and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. In the opinion of our management, the information contained herein reflects all adjustments necessary for a fair presentation of Workday’s results of operations, financial position, and cash flows. All such adjustments are of a normal, recurring nature. The results of operations for the quarter ended July 31, 2018 shown in this report are not necessarily indicative of the results to be expected for the full year ending January 31, 2019 . The unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements in our Annual Report on Form 10-K for the year ended January 31, 2018 , filed with the SEC on March 14, 2018. Certain prior period amounts reported in our condensed consolidated financial statements have been reclassified to conform to current period presentation. Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires us to make certain estimates, judgments, and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed consolidated financial statements as well as the reported amounts of revenues and expenses during the reporting period. These estimates include, but are not limited to, the determination of the period of benefit for deferred commissions, certain assumptions used in the valuation of equity awards, and the fair value of assets acquired and liabilities assumed through business combinations. Actual results could differ from those estimates and such differences could be material to our condensed consolidated financial position and results of operations. Segment Information We operate in one operating segment, cloud applications. Operating segments are defined as components of an enterprise where separate financial information is evaluated regularly by the chief operating decision maker, who is our chief executive officer, in deciding how to allocate resources and assessing performance. Our chief operating decision maker allocates resources and assesses performance based upon discrete financial information at the consolidated level.

Accounting Standards

Accounting Standards	6 Months Ended
	Jul. 31, 2018
Accounting Policies [Abstract]
Accounting Standards	Accounting Standards Recently Adopted Accounting Pronouncements In January 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (Subtopic 825-10) , which amends various aspects of the recognition, measurement, presentation, and disclosure of financial instruments. As of February 1, 2018, we adopted the applicable provisions of ASU No. 2016-01 as follows: • Marketable equity investments (readily determinable fair values): For our equity investments previously classified as available-for-sale equity investments, we are required to account for changes in fair value of these investments in the condensed consolidated statements of operations. We have applied the modified retrospective transition method upon adoption, resulting in no impact to our condensed consolidated financial statements as of February 1, 2018. • Non-marketable equity investments (no readily determinable fair values): For our equity investments previously classified as cost method investments that do not qualify for the net asset value practical expedient, we measure them at fair value or the measurement alternative. The measurement alternative is defined as cost, less impairment, adjusted for observable price changes from orderly transactions for identical or similar investments of the same issuer. Adjustments resulting from impairment, fair value, or observable price changes are accounted for in the condensed consolidated statements of operations. We adopted the guidance prospectively effective February 1, 2018, and there was no impact to our condensed consolidated financial statements. Going forward, the impact of this new standard could result in volatility in the condensed consolidated statements of operations. In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Transfers of Assets Other Than Inventory (Topic 740) , which requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Prior to the issuance of this ASU, existing guidance prohibited the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset had been sold to an outside party. We adopted this new standard effective February 1, 2018 using the modified retrospective transition method, resulting in a $0.4 million cumulative-effect adjustment to Accumulated deficit as of February 1, 2018. Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) , which requires the recognition of lease assets and lease liabilities on the balance sheet by lessees for those leases currently classified as operating leases under Accounting Standards Codification Topic 840 Leases. The guidance is effective for our fiscal year beginning February 1, 2019 and must be applied using a modified retrospective approach. Early adoption is permitted. We plan to adopt this new standard in the first quarter of our fiscal 2020. We continue to evaluate the effect of adopting this guidance on our condensed consolidated financial statements and related disclosures. Upon adoption, we will recognize right-of-use assets and operating lease liabilities on our condensed consolidated balance sheets, which will increase our total assets and total liabilities. We are evaluating the accounting, transition, and disclosure requirements of this standard and cannot currently estimate the financial statement impact of adoption. In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815) , to better align an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. The guidance is effective for our fiscal year beginning February 1, 2019 and must be applied using a modified retrospective approach. Early adoption is permitted. We plan to adopt this new standard in the first quarter of our fiscal 2020. We are evaluating the accounting, transition, and disclosure requirements of this standard and cannot currently estimate the financial statement impact of adoption. In February 2018, the FASB issued ASU No. 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income , which provides entities the option to reclassify tax effects stranded in accumulated other comprehensive income as a result of the 2017 Tax Cuts and Jobs Act (the "Tax Act") to retained earnings. The guidance is effective for our fiscal year beginning February 1, 2019 and must be applied either in the period of adoption or retrospectively to each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Act is recognized. Early adoption is permitted. We plan to adopt the new standard in the first quarter of our fiscal 2020 and do not expect it to have a material impact on our condensed consolidated financial statements. In June 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Non-employee Share-Based Payment Accounting , which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees, with certain exceptions. The guidance is effective for our fiscal year beginning February 1, 2019. Early adoption is permitted. We plan to adopt this new standard in the first quarter of our fiscal 2020 and do not expect it to have a material impact on our condensed consolidated financial statements.

Investments

Investments	6 Months Ended
	Jul. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Marketable Securities At July 31, 2018 , marketable securities consisted of the following (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value U.S. agency obligations $ 283,022 $ — $ (548 ) $ 282,474 U.S. treasury securities 541,060 4 (674 ) 540,390 Corporate bonds 373,800 40 (1,039 ) 372,801 Commercial paper 107,110 — — 107,110 $ 1,304,992 $ 44 $ (2,261 ) $ 1,302,775 Included in cash and cash equivalents $ 11,423 $ — $ — $ 11,423 Included in marketable securities $ 1,293,569 $ 44 $ (2,261 ) $ 1,291,352 At January 31, 2018 , marketable securities consisted of the following (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value U.S. agency obligations $ 683,551 $ — $ (1,127 ) $ 682,424 U.S. treasury securities 797,977 — (1,142 ) 796,835 Corporate bonds 470,259 16 (1,154 ) 469,121 Commercial paper 602,727 — — 602,727 $ 2,554,514 $ 16 $ (3,423 ) $ 2,551,107 Included in cash and cash equivalents $ 417,613 $ — $ (1 ) $ 417,612 Included in marketable securities $ 2,136,901 $ 16 $ (3,422 ) $ 2,133,495 We do not believe the unrealized losses represent other-than-temporary impairments based on our evaluation of available evidence, which includes our intent to hold these investments to maturity as of July 31, 2018 . The unrealized losses on marketable securities which have been in a net loss position for 12 months or more were not material as of July 31, 2018 . We classify our marketable securities as available-for-sale debt securities at the time of purchase and reevaluate such classification as of each balance sheet date. We consider all marketable securities as available for use in current operations, including those with maturity dates beyond one year, and therefore classify these securities as current assets in the accompanying condensed consolidated balance sheets. Marketable securities on the condensed consolidated balance sheets consist of securities with original maturities at the time of purchase greater than three months, and the remainder of the securities is included in Cash and cash equivalents. We sold $915 million and $181 million of our marketable securities during the three months ended July 31, 2018 and 2017 , respectively, and $942 million and $190 million of our marketable securities during the six months ended July 31, 2018 and 2017 , respectively. The realized losses from the sales were immaterial. Equity Investments Equity investments consisted of the following (in thousands): July 31, 2018 January 31, 2018 Marketable equity investments $ 1,451,961 $ 551,804 Non-marketable equity investments 30,405 28,005 $ 1,482,366 $ 579,809 Marketable equity investments consist of money market funds and are included in Cash and cash equivalents on the condensed consolidated balance sheets. During the three and six months ended July 31, 2018 , there were no unrealized gains or losses recognized for these investments. Non-marketable equity investments consist of investments in privately held companies without readily determinable fair values and are included in Other assets on the condensed consolidated balance sheets. During the three and six months ended July 31, 2018 , there were no adjustments made to the carrying value of the non-marketable equity investments as measured under the measurement alternative.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jul. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements We measure our cash equivalents, marketable securities, and foreign currency derivative contracts at fair value at each reporting period using a fair value hierarchy that requires that we maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s classification within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. Three levels of inputs may be used to measure fair value: Level 1 — Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2 — Other inputs that are directly or indirectly observable in the marketplace. Level 3 — Unobservable inputs that are supported by little or no market activity. Assets and Liabilities Measured at Fair Value on a Recurring Basis The following table presents information about our assets and liabilities that are measured at fair value on a recurring basis and their assigned levels within the valuation hierarchy as of July 31, 2018 (in thousands): Description Level 1 Level 2 Level 3 Total U.S. agency obligations $ — $ 282,474 $ — $ 282,474 U.S. treasury securities 540,390 — — 540,390 Corporate bonds — 372,801 — 372,801 Commercial paper — 107,110 — 107,110 Money market funds 1,451,961 — — 1,451,961 Foreign currency derivative assets — 19,173 — 19,173 Total assets $ 1,992,351 $ 781,558 $ — $ 2,773,909 Foreign currency derivative liabilities $ — $ 1,986 $ — $ 1,986 Total liabilities $ — $ 1,986 $ — $ 1,986 The following table presents information about our assets and liabilities that are measured at fair value on a recurring basis and their assigned levels within the valuation hierarchy as of January 31, 2018 (in thousands): Description Level 1 Level 2 Level 3 Total U.S. agency obligations $ — $ 682,424 $ — $ 682,424 U.S. treasury securities 796,835 — — 796,835 Corporate bonds — 469,121 — 469,121 Commercial paper — 602,727 — 602,727 Money market funds 551,804 — — 551,804 Foreign currency derivative assets — 98 — 98 Total assets $ 1,348,639 $ 1,754,370 $ — $ 3,103,009 Foreign currency derivative liabilities $ — $ 32,912 $ — $ 32,912 Total liabilities $ — $ 32,912 $ — $ 32,912 Fair Value Measurements of Other Financial Instruments The following table presents the carrying amounts and estimated fair values of our financial instruments that are not recorded at fair value on the condensed consolidated balance sheets (in thousands): July 31, 2018 January 31, 2018 Net Carrying Amount Estimated Fair Value Net Carrying Amount Estimated Fair Value 0.75% Convertible senior notes $ — $ — $ 341,509 $ 504,994 1.50% Convertible senior notes 226,877 390,623 221,378 385,550 0.25% Convertible senior notes 950,132 1,221,760 928,467 1,200,577 In June 2013, we completed an offering of $350 million of 0.75% convertible senior notes due July 15, 2018 ("2018 Notes"), which were subsequently converted by note holders during the three months ended July 31, 2018. In June 2013, concurrent with the 2018 Notes offering, we issued $250 million of 1.50% convertible senior notes due July 15, 2020 ("2020 Notes"). In September 2017, we completed an offering of $1.15 billion of 0.25% convertible senior notes due October 1, 2022 ("2022 Notes" and together with the 2018 Notes and 2020 Notes, referred to as the "Notes"). The estimated fair values of the Notes, which we have classified as Level 2 financial instruments, were determined based on the quoted bid prices of the Notes in an over-the-counter market on the last trading day of each reporting period. The if-converted value of the 2020 Notes exceeded the principal amount by $129 million . The if-converted value of the 2022 Notes was less than the principal amount by $180 million . The if-converted values were determined based on the closing price of our common stock of $124.02 on July 31, 2018 . For further information, see Note 10.

Deferred Costs

Deferred Costs	6 Months Ended
	Jul. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred Costs	Deferred Costs Deferred costs, which primarily consist of deferred sales commissions, were $207 million and $204 million as of July 31, 2018 and January 31, 2018 , respectively. Amortization expense for the deferred costs was $17 million and $14 million for the three months ended July 31, 2018 and 2017 , respectively, and $33 million and $28 million for the six months ended July 31, 2018 and 2017 , respectively. There was no impairment loss in relation to the costs capitalized for the periods presented.

Property and Equipment, Net

Property and Equipment, Net	6 Months Ended
	Jul. 31, 2018
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): July 31, 2018 January 31, 2018 Land $ 13,199 $ 8,451 Buildings 343,904 255,093 Computers, equipment, and software 474,669 411,177 Computers, equipment, and software acquired under capital leases 11,677 13,848 Furniture and fixtures 35,270 34,809 Leasehold improvements 145,856 132,209 Property and equipment, gross (1) 1,024,575 855,587 Less accumulated depreciation and amortization (346,050 ) (308,978 ) Property and equipment, net $ 678,525 $ 546,609 (1) Property and equipment, gross includes construction-in-progress for owned real estate projects of $244 million and $177 million that have not yet been placed in service as of July 31, 2018 and January 31, 2018 , respectively. Depreciation expense totaled $36 million and $28 million for the three months ended July 31, 2018 and 2017 , respectively, and $69 million and $55 million for the six months ended July 31, 2018 and 2017 , respectively. Interest costs capitalized to property and equipment totaled $2 million and $2 million for the three months ended July 31, 2018 and 2017 , respectively, and $4 million and $3 million for the six months ended July 31, 2018 and 2017 , respectively.

Acquisition-related Intangible

Acquisition-related Intangible Assets, Net	6 Months Ended
	Jul. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Acquisition-related Intangible Assets, Net	Acquisition-related Intangible Assets, Net Acquisition-related intangible assets, net consisted of the following (in thousands): July 31, 2018 January 31, 2018 Acquired developed technology $ 81,800 $ 69,700 Customer relationship assets 1,000 1,000 82,800 70,700 Less accumulated amortization (46,873 ) (36,466 ) Acquisition-related intangible assets, net $ 35,927 $ 34,234 In the second quarter of fiscal 2019, we completed two acquisitions resulting in an increase of $12 million and $16 million in acquired developed technology and goodwill, respectively. Amortization expense related to acquired developed technology and customer relationship assets was $5 million for each of the three month periods ended July 31, 2018 and 2017 , and $10 million for each of the six month periods ended July 31, 2018 and 2017 , respectively. As of July 31, 2018 , our future estimated amortization expense related to acquired developed technology and customer relationship assets is as follows (in thousands): Fiscal Period: 2019 $ 11,770 2020 15,022 2021 5,058 2022 3,400 2023 677 Total $ 35,927

Other Assets

Other Assets	6 Months Ended
	Jul. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	Other Assets Other assets consisted of the following (in thousands): July 31, 2018 January 31, 2018 Non-marketable equity and other investments $ 32,405 $ 29,205 Prepayments for computing infrastructure platform 9,369 13,588 Technology patents, net 11,396 11,217 Acquired land leasehold interest, net 9,518 9,570 Deposits 4,823 4,492 Net deferred tax assets 2,201 1,884 Other 51,362 39,762 Total $ 121,074 $ 109,718

Derivative Instruments

Derivative Instruments	6 Months Ended
	Jul. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments We conduct business on a global basis in multiple foreign currencies, subjecting Workday to foreign currency risk. To mitigate this risk, we utilize hedging contracts as described below. We do not enter into any derivatives for trading or speculative purposes. Our foreign currency contracts are classified within Level 2 of the fair value hierarchy because the valuation inputs are based on quoted prices and market observable data of similar instruments in active markets, such as currency spot and forward rates. Cash Flow Hedges We are exposed to foreign currency fluctuations resulting from customer contracts denominated in foreign currencies. We have a hedging program in which we enter into foreign currency forward contracts related to certain customer contracts. We designate these forward contracts as cash flow hedging instruments as the accounting criteria for such designation have been met. The effective portion of the gains or losses resulting from changes in the fair value of these hedges is recorded in Accumulated other comprehensive income (loss) ("OCI") on the condensed consolidated balance sheets and will be subsequently reclassified to the related revenue line item on the condensed consolidated statements of operations in the same period that the underlying revenues are earned. The changes in value of these contracts resulting from changes in forward points are excluded from the assessment of hedge effectiveness and are recorded as incurred in Other income (expense), net on the condensed consolidated statements of operations. Cash flows from such forward contracts are classified as operating activities. As of July 31, 2018 and January 31, 2018 , we had outstanding foreign currency forward contracts designated as cash flow hedges with total notional values of $655 million and $549 million , respectively. All contracts have maturities not greater than 36 months. The notional value represents the amount that will be bought or sold upon maturity of the forward contract. Foreign Currency Forward Contracts not Designated as Hedges We also enter into foreign currency forward contracts to hedge a portion of our net outstanding monetary assets and liabilities. These forward contracts are not designated as hedging instruments under applicable accounting guidance, and therefore all changes in the fair value of the forward contracts are recorded in Other income (expense), net on the condensed consolidated statements of operations. These forward contracts are intended to offset the foreign currency gains or losses associated with the underlying monetary assets and liabilities. Cash flows from such forward contracts are classified as operating activities. As of July 31, 2018 and January 31, 2018 , we had outstanding forward contracts with total notional values of $201 million and $75 million . The fair values of outstanding derivative instruments were as follows (in thousands): Condensed Consolidated Balance Sheets Location July 31, 2018 January 31, 2018 Derivative Assets: Foreign currency forward contracts designated as cash flow hedges Prepaid expenses and other current assets $ 9,717 $ 15 Foreign currency forward contracts designated as cash flow hedges Other assets 9,071 4 Foreign currency forward contracts not designated as hedges Prepaid expenses and other current assets 347 79 Foreign currency forward contracts not designated as hedges Other assets 38 — Total Derivative Assets $ 19,173 $ 98 Derivative Liabilities: Foreign currency forward contracts designated as cash flow hedges Accrued expenses and other current liabilities $ 1,022 $ 18,355 Foreign currency forward contracts designated as cash flow hedges Other liabilities 81 11,650 Foreign currency forward contracts not designated as hedges Accrued expenses and other current liabilities 883 2,805 Foreign currency forward contracts not designated as hedges Other liabilities — 102 Total Derivative Liabilities $ 1,986 $ 32,912 Gains (losses) associated with foreign currency forward contracts designated as cash flow hedges were as follows (in thousands): Condensed Consolidated Statements of Operations and Statements of Comprehensive Loss Locations Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 Gains (losses) recognized in OCI (effective portion) (1) Net change in market value of effective foreign currency forward exchange contracts $ 17,891 $ (22,923 ) $ 36,165 $ (23,898 ) Gains (losses) reclassified from OCI into income (effective portion) Revenues (1,960 ) 473 (3,077 ) 707 Gains (losses) recognized in income (amount excluded from effectiveness testing and ineffective portion) Other income (expense), net 4,027 767 6,258 1,390 (1) Of the total effective portion of foreign currency forward contracts designated as cash flow hedges as of July 31, 2018 , net losses of $6 million are expected to be reclassified out of OCI within the next 12 months. Gains (losses) associated with foreign currency forward contracts not designated as cash flow hedges were as follows (in thousands): Condensed Consolidated Statements of Operations Location Three Months Ended July 31, Six Months Ended July 31, Derivative Type 2018 2017 2018 2017 Foreign currency forward contracts not designated as hedges Other income (expense), net $ 1,884 $ (2,619 ) $ 3,678 $ (2,625 ) We are subject to master netting agreements with certain counterparties of the foreign exchange contracts, under which we are permitted to net settle transactions of the same currency with a single net amount payable by one party to the other. It is our policy to present the derivatives gross on the condensed consolidated balance sheets. Our foreign currency forward contracts are not subject to any credit contingent features or collateral requirements. We manage our exposure to counterparty risk by entering into contracts with a diversified group of major financial institutions and by actively monitoring outstanding positions. As of July 31, 2018 , information related to these offsetting arrangements was as follows (in thousands): Gross Amounts of Recognized Assets Gross Amounts Offset on the Condensed Consolidated Balance Sheets Net Amounts of Assets Presented on the Condensed Consolidated Balance Sheets Gross Amounts Not Offset on the Condensed Consolidated Balance Sheets Net Assets Exposed Financial Instruments Cash Collateral Received Derivative Assets: Counterparty A $ 5,527 $ — $ 5,527 $ (78 ) $ — $ 5,449 Counterparty B 11,340 — 11,340 (1,541 ) — 9,799 Counterparty C 2,306 — 2,306 (367 ) — 1,939 Total $ 19,173 $ — $ 19,173 $ (1,986 ) $ — $ 17,187 Gross Amounts of Recognized Liabilities Gross Amounts Offset on the Condensed Consolidated Balance Sheets Net Amounts of Liabilities Presented on the Condensed Consolidated Balance Sheets Gross Amounts Not Offset on the Condensed Consolidated Balance Sheets Net Liabilities Exposed Financial Instruments Cash Collateral Pledged Derivative Liabilities: Counterparty A $ 78 $ — $ 78 $ (78 ) $ — $ — Counterparty B 1,541 — 1,541 (1,541 ) — — Counterparty C 367 — 367 (367 ) — — Total $ 1,986 $ — $ 1,986 $ (1,986 ) $ — $ —

Convertible Senior Notes, Net

Convertible Senior Notes, Net	6 Months Ended
	Jul. 31, 2018
Debt Disclosure [Abstract]
Convertible Senior Notes, Net	Convertible Senior Notes, Net Convertible Senior Notes In June 2013, we issued 0.75% convertible senior notes due July 15, 2018 with a principal amount of $350 million . The 2018 Notes were unsecured, unsubordinated obligations, and interest was payable in cash in arrears at a fixed rate of 0.75% on January 15 and July 15 of each year. During the three months ended July 31, 2018, the 2018 Notes were converted by note holders and we repaid the $350 million principal balance in cash. We also distributed approximately 1.5 million shares of our Class A common stock to note holders during the three months ended July 31, 2018, which represents the conversion value in excess of the principal amount. In June 2013, we issued 1.50% convertible senior notes due July 15, 2020 with a principal amount of $250 million . The 2020 Notes are unsecured, unsubordinated obligations, and interest is payable in cash in arrears at a fixed rate of 1.50% on January 15 and July 15 of each year. The 2020 Notes mature on July 15, 2020 unless repurchased or converted in accordance with their terms prior to such date. We cannot redeem the 2020 Notes prior to maturity. In September 2017, we issued 0.25% convertible senior notes due October 1, 2022 with a principal amount of $1.15 billion . The 2022 Notes are unsecured, unsubordinated obligations, and interest is payable in cash in arrears at a fixed rate of 0.25% on April 1 and October 1 of each year. The 2022 Notes mature on October 1, 2022 unless repurchased or converted in accordance with their terms prior to such date. We cannot redeem the 2022 Notes prior to maturity. The terms of the Notes are governed by Indentures by and between us and Wells Fargo Bank, National Association, as Trustee (the "Indentures"). Upon conversion, holders of the Notes will receive cash, shares of Class A common stock, or a combination of cash and shares of Class A common stock, at our election. For the 2020 Notes, the initial conversion rate is 12.2340 shares of Class A common stock per $1,000 principal amount, which is equal to an initial conversion price of approximately $81.74 per share of Class A common stock, subject to adjustment. Prior to the close of business on March 13, 2020, conversion of the 2020 Notes is subject to the satisfaction of certain conditions, as described below. For the 2022 Notes, the initial conversion rate is 6.7982 shares of Class A common stock per $1,000 principal amount, which is equal to an initial conversion price of approximately $147.10 per share of Class A common stock, subject to adjustment. Prior to the close of business on May 31, 2022, conversion of the 2022 Notes is subject to the satisfaction of certain conditions, as described below. Holders of the Notes who convert their Notes in connection with certain corporate events that constitute a make-whole fundamental change (as defined in the Indentures) are, under certain circumstances, entitled to an increase in the conversion rate. Additionally, in the event of a corporate event that constitutes a fundamental change (as defined in the Indentures), holders of the Notes may require us to repurchase all or a portion of their Notes at a price equal to 100% of the principal amount of the Notes, plus any accrued and unpaid interest. Holders of the 2020 Notes and 2022 Notes may convert all or a portion of their Notes prior to the close of business on March 13, 2020 and May 31, 2022, respectively, in multiples of $1,000 principal amount, only under the following circumstances: • if the last reported sale price of Class A common stock for at least 20 trading days during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding fiscal quarter is greater than or equal to 130% of the conversion price of the respective Notes on each applicable trading day; • during the five business day period after any five consecutive trading day period in which the trading price per $1,000 principal amount of the respective Notes for each day of that five day consecutive trading day period was less than 98% of the product of the last reported sale price of Class A common stock and the conversion rate of the respective Notes on such trading day; or • upon the occurrence of specified corporate events, as noted in the Indentures. On or after March 15, 2020 for the 2020 Notes and June 1, 2022 for the 2022 Notes, holders of the respective Notes may convert their Notes at any time until the close of business on the second scheduled trading day immediately preceding the respective maturity date of their Notes. In accounting for the issuance of the Notes, we separated each of the Notes into liability and equity components. The carrying amounts of the liability components were calculated by measuring the fair value of similar liabilities that do not have associated convertible features. The carrying amount of the equity components representing the conversion option were determined by deducting the fair value of the liability components from the par value of the respective Notes. These differences represent debt discounts that are amortized to interest expense over the respective terms of the Notes using the effective interest rate method. The equity components are not remeasured as long as they continue to meet the conditions for equity classification. In accounting for the issuance costs related to the Notes, we allocated the total amount of issuance costs incurred to liability and equity components based on their relative values. Issuance costs attributable to the liability components are being amortized on a straight-line basis, which approximates the effective interest rate method, to interest expense over the respective terms of the Notes. The issuance costs attributable to the equity components were netted against the respective equity components in Additional paid-in capital. For the 2018 Notes, we recorded liability issuance costs of $7 million and equity issuance costs of $2 million . Amortization expense for the liability issuance costs was $0.3 million and $0.4 million for the three months ended July 31, 2018 and 2017 , respectively, and $0.6 million and $0.7 million for the six months ended July 31, 2018 and 2017 , respectively. For the 2020 Notes, we recorded liability issuance costs of $5 million and equity issuance costs of $2 million . Amortization expense for the liability issuance costs was $0.2 million and $0.3 million for each of the three and six month periods ended July 31, 2018 and 2017 . For the 2022 Notes, we recorded liability issuance costs of $14 million and equity issuance costs of $4 million . Amortization expense for the liability issuance costs was $0.7 million and $1.4 million for the three and six months ended July 31, 2018 . The Notes, net consisted of the following (in thousands): July 31, 2018 January 31, 2018 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes Principal amounts: Principal $ — $ 250,000 $ 1,150,000 $ 350,000 $ 250,000 $ 1,150,000 Unamortized debt discount — (21,806 ) (187,952 ) (7,850 ) (26,968 ) (208,188 ) Unamortized debt issuance costs — (1,317 ) (11,916 ) (641 ) (1,654 ) (13,345 ) Net carrying amount $ — $ 226,877 $ 950,132 $ 341,509 $ 221,378 $ 928,467 Carrying amount of the equity component (1) $ 74,887 $ 66,007 $ 219,702 $ 74,892 $ 66,007 $ 219,702 (1) Included on the condensed consolidated balance sheets within Additional paid-in capital, net of $2 million , $2 million , and $4 million for the 2018 Notes, 2020 Notes, and 2022 Notes, respectively, in equity issuance costs. As of July 31, 2018 , the 2020 Notes and 2022 Notes have remaining lives of approximately 23 months and 50 months , respectively. For more than 20 trading days during the 30 consecutive trading days ended April 30, 2018 and July 31, 2018 , the last reported sale price of our Class A common stock exceeded 130% of the conversion price of the 2020 Notes. As a result, the 2020 Notes were convertible at the option of the holders during the second quarter of fiscal 2019 and will continue to be convertible during the third quarter of fiscal 2019. Accordingly, the 2020 Notes are classified as current on the condensed consolidated balance sheet as of July 31, 2018 . From May 1, 2018 through the date of this filing, the amount of the principal balance of the 2020 Notes that has been converted or for which conversion has been requested was not material. The effective interest rates of the liability components of the 2018 Notes, 2020 Notes, and 2022 Notes are 5.75% , 6.25% , and 4.60% , respectively. These interest rates were based on the interest rates of similar liabilities at the time of issuance that did not have associated convertible features. The following table sets forth total interest expense recognized related to the Notes (in thousands): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes Contractual interest expense $ 540 $ 938 $ 719 $ 657 $ 937 $ — $ 1,196 $ 1,875 $ 1,438 $ 1,313 $ 1,875 $ — Interest cost related to amortization of debt issuance costs 289 169 715 352 167 — 641 337 1,429 704 335 — Interest cost related to amortization of the debt discount 3,567 2,601 10,175 4,104 2,444 — 7,850 5,162 20,236 8,148 4,850 — We capitalized interest costs related to the Notes of $2 million and $2 million for the three months ended July 31, 2018 and 2017 , respectively, and $4 million and $3 million for the six months ended July 31, 2018 and 2017 , respectively. Notes Hedges In connection with the issuance of the Notes, we entered into convertible note hedge transactions with respect to our Class A common stock ("Purchased Options"). The Purchased Options relating to the 2018 Notes gave us the option to purchase, subject to anti-dilution adjustments substantially identical to those in the 2018 Notes, approximately 4.2 million shares of our Class A common stock for $83.28 per share, exercisable upon conversion of the 2018 Notes. During the three months ended July 31, 2018, we received approximately 1.5 million shares of our Class A common stock from the exercise of the Purchased Options relating to the 2018 Notes. These shares are held as treasury stock as of July 31, 2018. The Purchased Options relating to the 2020 Notes give us the option to purchase, subject to anti-dilution adjustments substantially identical to those in the 2020 Notes, approximately 3.1 million shares of our Class A common stock for $81.74 per share, exercisable upon conversion of the 2020 Notes. The Purchased Options relating to the 2022 Notes give us the option to purchase, subject to anti-dilution adjustments substantially identical to those in the 2022 Notes, approximately 7.8 million shares of our Class A common stock for $147.10 per share, exercisable upon conversion of the 2022 Notes. The Purchased Options will expire in 2020 for the 2020 Notes and in 2022 for the 2022 Notes, if not exercised earlier. The Purchased Options are intended to offset potential economic dilution to our Class A common stock upon any conversion of the Notes. The Purchased Options are separate transactions and are not part of the terms of the Notes. We paid an aggregate amount of $144 million for the Purchased Options relating to the 2018 Notes and 2020 Notes, and $176 million for the Purchased Options relating to the 2022 Notes. The amount paid for the Purchased Options is included in Additional paid-in capital on the condensed consolidated balance sheets. Warrants In connection with the issuance of the Notes, we also entered into warrant transactions to sell warrants ("Warrants") to acquire, subject to anti-dilution adjustments, up to approximately 4.2 million shares over 60 scheduled trading days beginning in October 2018, 3.1 million shares over 60 scheduled trading days beginning in October 2020, and 7.8 million shares over 60 scheduled trading days beginning in January 2023 of our Class A common stock at an exercise price of $107.96 , $107.96 , and $213.96 per share, respectively. If the Warrants are not exercised on their exercise dates, they will expire. If the market value per share of our Class A common stock exceeds the applicable exercise price of the Warrants, the Warrants will have a dilutive effect on our earnings per share assuming that we are profitable. The Warrants are separate transactions and are not part of the terms of the Notes or the Purchased Options. We received aggregate proceeds of $93 million from the sale of the Warrants related to the 2018 Notes and the 2020 Notes, and $81 million from the sale of the Warrants related to the 2022 Notes. The proceeds from the sale of the Warrants are recorded in Additional paid-in capital on the condensed consolidated balance sheets.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jul. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Facility and Computing Infrastructure-related Commitments We have entered into non-cancelable agreements for certain of our offices and data centers with various expiration dates. Certain of our office leases are with an affiliate of our Chairman, David Duffield, who is also a significant stockholder (see Note 17). Our operating lease agreements generally provide for rental payments on a graduated basis and for options to renew, which could increase future minimum lease payments if exercised. This includes payments for office and data center square footage as well as data center power capacity for certain data centers. We generally recognize these expenses on a straight-line basis over the period in which we benefit from the lease. We have accrued for rent expense incurred but not paid. Total rent expense was $24 million and $20 million for the three months ended July 31, 2018 and 2017 , respectively, and $47 million and $39 million for the six months ended July 31, 2018 and 2017 , respectively. In January 2014, we entered into a 95 -year lease for a 6.9 -acre parcel of vacant land in Pleasanton, California, under which we paid $2 million for base rent from commencement through December 31, 2020. Annual rent payments of $0.2 million plus increases based on increases in the consumer price index begin on January 1, 2021 and continue through the end of the lease. Additionally, we have entered into non-cancelable agreements with computing infrastructure vendors with various expiration dates. Legal Matters We are a party to various legal proceedings and claims that arise in the ordinary course of business. We make a provision for a liability relating to legal matters when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. These provisions are reviewed at least quarterly and adjusted to reflect the impacts of negotiations, settlements, rulings, advice of legal counsel, and other information and events pertaining to a particular matter. In our opinion, as of July 31, 2018 , there was not at least a reasonable possibility that we had incurred a material loss, or a material loss in excess of a recorded accrual, with respect to such loss contingencies.

Common Stock and Stockholders'

Common Stock and Stockholders' Equity	6 Months Ended
	Jul. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Common Stock and Stockholders' Equity	Common Stock and Stockholders’ Equity Common Stock As of July 31, 2018 , there were 149 million shares of Class A common stock, net of treasury stock, and 68 million shares of Class B common stock outstanding. The rights of the holders of Class A common stock and Class B common stock are identical, except with respect to voting and conversion. Each share of Class A common stock is entitled to one vote per share and each share of Class B common stock is entitled to 10 votes per share. Each share of Class B common stock can be converted into a share of Class A common stock at any time at the option of the holder. Employee Equity Plans Our 2012 Equity Incentive Plan ("EIP") serves as the successor to our 2005 Stock Plan (together with the EIP, the "Stock Plans"). Pursuant to the terms of the EIP, the share reserve increased by 11 million shares in March 2018. As of July 31, 2018 , we had approximately 66 million shares of Class A common stock available for future grants. We also have a 2012 Employee Stock Purchase Plan ("ESPP"). Under the ESPP, eligible employees are granted options to purchase shares at the lower of 85% of the fair market value of the stock at the time of grant or 85% of the fair market value at the time of exercise. Options to purchase shares are granted twice yearly on or about June 1 and December 1 and exercisable on or about the succeeding November 30 and May 31, respectively, of each year. As of July 31, 2018 , approximately 7 million shares of Class A common stock were available for issuance under the ESPP. Restricted Stock Units The Stock Plans provide for the issuance of restricted stock units ("RSUs") to employees and non-employees. RSUs generally vest over four years. A summary of information related to RSU activity during the six months ended July 31, 2018 is as follows: Number of Shares Weighted-Average Grant Date Fair Value Balance as of January 31, 2018 12,819,516 $ 84.77 RSUs granted 5,287,486 125.67 RSUs vested (3,449,505 ) 83.16 RSUs forfeited (460,192 ) 93.29 Balance as of July 31, 2018 14,197,305 $ 100.12 As of July 31, 2018 , there was a total of $1.3 billion in unrecognized compensation cost related to unvested RSUs, which is expected to be recognized over a weighted-average period of approximately 3.0 years. Performance-based Restricted Stock Units During fiscal 2018, 0.4 million shares of performance-based restricted stock units ("PRSUs") were granted to all employees other than executive management that included both service conditions and performance conditions related to company-wide goals. These performance conditions were met and the PRSUs vested on March 15, 2018. During the six months ended July 31, 2018 , we recognized $7 million in compensation cost related to these PRSUs. Additionally, during the second quarter of fiscal 2019, 0.4 million shares of PRSUs were granted to all employees other than executive management that included both service conditions and performance conditions related to company-wide goals. We expect to grant additional shares related to this program for employees hired in fiscal 2019. These PRSU awards will vest if the performance conditions are achieved for the fiscal year ended January 31, 2019 and if the individual employee continues to provide service through the vesting date of March 15, 2019. During the three and six months ended July 31, 2018 , we recognized $9 million in compensation cost related to these PRSUs, and there is a total of $45 million in unrecognized compensation cost which is expected to be recognized over a weighted-average period of approximately seven months. Stock Options The Stock Plans provide for the issuance of incentive and nonstatutory options to employees and non-employees. Options issued under the Stock Plans generally are exercisable for periods not to exceed 10 years and generally vest over five years. A summary of information related to stock option activity during the six months ended July 31, 2018 is as follows (in millions, except share and per share data): Outstanding Stock Options Weighted- Average Exercise Price Aggregate Intrinsic Value Balance as of January 31, 2018 6,595,486 $ 4.23 $ 763 Stock options granted — — Stock options exercised (751,957 ) 4.64 Stock options canceled (12,000 ) 0.40 Balance as of July 31, 2018 5,831,529 $ 4.19 $ 699 Vested as of July 31, 2018 5,831,529 $ 4.19 $ 699 Exercisable as of July 31, 2018 5,831,529 $ 4.19 $ 699 As of July 31, 2018 , there was no unrecognized compensation cost related to unvested stock options.

Unearned Revenue and Performanc

Unearned Revenue and Performance Obligations	6 Months Ended
	Jul. 31, 2018
Revenue from Contract with Customer [Abstract]
Unearned Revenue and Performance Obligations	Unearned Revenue and Performance Obligations $507 million and $398 million of subscription services revenue was recognized during the three months ended July 31, 2018 and 2017, respectively, that was included in the unearned revenue balances as of April 30, 2018 and 2017, respectively. $899 million and $673 million of subscription services revenue was recognized during the six months ended July 31, 2018 and 2017 , respectively, that was included in the unearned revenue balances as of January 31, 2018 and 2017, respectively. Professional services revenue recognized in the same periods from unearned revenue balances at the beginning of the respective periods was not material. Transaction Price Allocated to the Remaining Performance Obligations As of July 31, 2018 , approximately $5.5 billion of revenue is expected to be recognized from remaining performance obligations for subscription contracts. We expect to recognize revenue on approximately two thirds of these remaining performance obligations over the next 24 months , with the balance recognized thereafter. Revenue from remaining performance obligations for professional services contracts as of July 31, 2018 was not material.

Other Income (Expense), Net

Other Income (Expense), Net	6 Months Ended
	Jul. 31, 2018
Other Income and Expenses [Abstract]
Other Income (Expense), Net	Other Income (Expense), Net Other income (expense), net consisted of the following (in thousands): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 Interest income $ 14,692 $ 5,051 $ 26,928 $ 9,080 Interest expense (1) (17,515 ) (6,840 ) (35,817 ) (13,826 ) Other income (expense) 4,436 2,727 6,654 4,021 Other income (expense), net $ 1,613 $ 938 $ (2,235 ) $ (725 ) (1) Interest expense includes the contractual interest expense related to the 2018 Notes, 2020 Notes, and 2022 Notes and non-cash interest expense related to amortization of the debt discount and debt issuance costs, net of capitalized interest costs (see Note 10).

Income Taxes

Income Taxes	6 Months Ended
	Jul. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We compute the year-to-date income tax provision by applying the estimated annual effective tax rate to the year-to-date pre-tax income or loss and adjusting for discrete tax items in the period. We reported an income tax benefit of $2 million and an income tax provision of $4 million for the six months ended July 31, 2018 and 2017, respectively. The income tax benefit for the six months ended July 31, 2018 was primarily attributable to the application of intra-period tax allocation rules related to gains from comprehensive income and excess tax benefits in certain foreign jurisdictions from share-based compensation. The income tax benefit was partially offset by state taxes and income tax expenses in profitable foreign jurisdictions. The income tax provision for the six months ended July 31, 2017 was primarily attributable to state taxes and income tax expenses in profitable foreign jurisdictions. We are subject to income tax audits in the U.S. and foreign jurisdictions. We record liabilities related to uncertain tax positions and believe that we have provided adequate reserves for income tax uncertainties in all open tax years. Due to our history of tax losses, all years remain open to tax audit. We periodically evaluate the realizability of our net deferred tax assets based on all available evidence, both positive and negative. The realization of net deferred tax assets is dependent on our ability to generate sufficient future taxable income during periods prior to the expiration of tax attributes to fully utilize these assets. As of July 31, 2018, we continue to maintain a full valuation allowance on our deferred tax assets except in certain jurisdictions. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act , which allows companies to record provisional amounts for the Tax Act during a measurement period not to extend beyond one year of the enactment date. As of July 31, 2018, we did not have any significant adjustments to our initial assessment performed as of January 31, 2018. We will continue our analysis for all the tax effects of the Tax Act, which are still subject to change during the measurement period, and anticipate further guidance on accounting interpretations from the FASB and application of the Tax Act from the Department of the Treasury.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jul. 31, 2018
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per Share Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, net of treasury stock. Diluted net loss per share is computed by giving effect to all potential shares of common stock, including our outstanding stock options, outstanding warrants, common stock related to unvested early exercised stock options, common stock related to unvested restricted stock units and awards and convertible senior notes to the extent dilutive, and common stock issuable pursuant to the ESPP. Basic and diluted net loss per share was the same for each period presented, as the inclusion of all potential common shares outstanding would have been anti-dilutive. The net loss per share attributable to common stockholders is allocated based on the contractual participation rights of the Class A common shares and Class B common shares as if the loss for the period had been distributed. As the liquidation and dividend rights are identical, the net loss attributable to common stockholders is allocated on a proportionate basis. The following table presents the calculation of basic and diluted net loss attributable to common stockholders per share (in thousands, except per share data): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 Class A Class B Class A Class B Class A Class B Class A Class B Net loss per share, basic and diluted: Numerator: Allocation of distributed net loss $ (58,776 ) $ (27,380 ) $ (52,997 ) $ (29,535 ) $ (108,888 ) $ (51,678 ) $ (93,625 ) $ (52,951 ) Denominator: Weighted-average common shares outstanding 147,310 68,622 132,940 74,088 145,475 69,042 131,232 74,221 Basic and diluted net loss per share $ (0.40 ) $ (0.40 ) $ (0.40 ) $ (0.40 ) $ (0.75 ) $ (0.75 ) $ (0.71 ) $ (0.71 ) The anti-dilutive securities excluded from the weighted-average shares used to calculate the diluted net loss per common share were as follows (in thousands): As of July 31, 2018 2017 Outstanding common stock options 5,832 7,502 Shares subject to repurchase — 30 Unvested restricted stock awards, units, and PRSUs 14,629 14,414 Shares related to the convertible senior notes 15,079 7,261 Shares subject to warrants related to the issuance of convertible senior notes 15,079 7,261 Shares issuable pursuant to the ESPP 418 375 51,037 36,843

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jul. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions We lease certain office space from an affiliate of our Chairman, Mr. Duffield, adjacent to our corporate headquarters in Pleasanton, California, under various lease agreements. The average term of the agreements is 9 years. The total rent expense under these agreements was $2 million for each of the three month periods ended July 31, 2018 and 2017 , respectively, and $5 million and $4 million for the six months ended July 31, 2018 and 2017 , respectively.

Geographic Information

Geographic Information	6 Months Ended
	Jul. 31, 2018
Segment Reporting [Abstract]
Geographic Information	Geographic Information Disaggregation of Revenue We sell our subscription contracts and related services in two primary geographical markets: to customers located in the United States, and to customers located outside of the United States. Revenue by geography is generally based on the address of the customer as specified in our master subscription agreement. The following table sets forth revenue by geographic area (in thousands): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 United States $ 515,257 $ 419,466 $ 995,339 $ 802,637 Other countries 156,463 105,854 295,024 202,544 Total $ 671,720 $ 525,320 $ 1,290,363 $ 1,005,181 No single country other than the United States had revenues greater than 10% of total revenues for the three and six months ended July 31, 2018 and 2017 . No customer individually accounted for more than 10% of our trade and other receivables, net as of July 31, 2018 or January 31, 2018 . Long-Lived Assets We attribute our long-lived assets, which primarily consist of property and equipment, to a country based on the physical location of the assets. The following table sets forth Property and equipment, net by geographic area (in thousands): July 31, 2018 January 31, 2018 United States $ 607,975 $ 479,996 Ireland 55,973 52,904 Other countries 14,577 13,709 Total $ 678,525 $ 546,609

Subsequent Events

Subsequent Events	6 Months Ended
	Jul. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Event On August 1, 2018, we completed our previously announced acquisition of Adaptive Insights, Inc. ("Adaptive Insights"), a provider of cloud-based software for business planning. Upon acquisition, Adaptive Insights became our wholly-owned subsidiary. The preliminary total purchase consideration was approximately $1.5 billion , consisting principally of cash payments. The purchase price will be allocated to the tangible and intangible assets acquired and liabilities assumed based on their fair values at the acquisition date. We are currently performing the procedures necessary to determine the purchase price allocation, and we will record our initial fair value estimates during the three months ending October 31, 2018.

Overview and Basis of Present28

Overview and Basis of Presentation (Policies)	6 Months Ended
	Jul. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States ("GAAP") and applicable rules and regulations of the Securities and Exchange Commission ("SEC") regarding interim financial reporting. The condensed consolidated financial statements include the results of Workday, Inc. and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. In the opinion of our management, the information contained herein reflects all adjustments necessary for a fair presentation of Workday’s results of operations, financial position, and cash flows. All such adjustments are of a normal, recurring nature. The results of operations for the quarter ended July 31, 2018 shown in this report are not necessarily indicative of the results to be expected for the full year ending January 31, 2019 . The unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements in our Annual Report on Form 10-K for the year ended January 31, 2018 , filed with the SEC on March 14, 2018. Certain prior period amounts reported in our condensed consolidated financial statements have been reclassified to conform to current period presentation.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires us to make certain estimates, judgments, and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed consolidated financial statements as well as the reported amounts of revenues and expenses during the reporting period. These estimates include, but are not limited to, the determination of the period of benefit for deferred commissions, certain assumptions used in the valuation of equity awards, and the fair value of assets acquired and liabilities assumed through business combinations. Actual results could differ from those estimates and such differences could be material to our condensed consolidated financial position and results of operations.
Segment Information	Segment Information We operate in one operating segment, cloud applications. Operating segments are defined as components of an enterprise where separate financial information is evaluated regularly by the chief operating decision maker, who is our chief executive officer, in deciding how to allocate resources and assessing performance. Our chief operating decision maker allocates resources and assesses performance based upon discrete financial information at the consolidated level.
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements In January 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (Subtopic 825-10) , which amends various aspects of the recognition, measurement, presentation, and disclosure of financial instruments. As of February 1, 2018, we adopted the applicable provisions of ASU No. 2016-01 as follows: • Marketable equity investments (readily determinable fair values): For our equity investments previously classified as available-for-sale equity investments, we are required to account for changes in fair value of these investments in the condensed consolidated statements of operations. We have applied the modified retrospective transition method upon adoption, resulting in no impact to our condensed consolidated financial statements as of February 1, 2018. • Non-marketable equity investments (no readily determinable fair values): For our equity investments previously classified as cost method investments that do not qualify for the net asset value practical expedient, we measure them at fair value or the measurement alternative. The measurement alternative is defined as cost, less impairment, adjusted for observable price changes from orderly transactions for identical or similar investments of the same issuer. Adjustments resulting from impairment, fair value, or observable price changes are accounted for in the condensed consolidated statements of operations. We adopted the guidance prospectively effective February 1, 2018, and there was no impact to our condensed consolidated financial statements. Going forward, the impact of this new standard could result in volatility in the condensed consolidated statements of operations. In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Transfers of Assets Other Than Inventory (Topic 740) , which requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Prior to the issuance of this ASU, existing guidance prohibited the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset had been sold to an outside party. We adopted this new standard effective February 1, 2018 using the modified retrospective transition method, resulting in a $0.4 million cumulative-effect adjustment to Accumulated deficit as of February 1, 2018. Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) , which requires the recognition of lease assets and lease liabilities on the balance sheet by lessees for those leases currently classified as operating leases under Accounting Standards Codification Topic 840 Leases. The guidance is effective for our fiscal year beginning February 1, 2019 and must be applied using a modified retrospective approach. Early adoption is permitted. We plan to adopt this new standard in the first quarter of our fiscal 2020. We continue to evaluate the effect of adopting this guidance on our condensed consolidated financial statements and related disclosures. Upon adoption, we will recognize right-of-use assets and operating lease liabilities on our condensed consolidated balance sheets, which will increase our total assets and total liabilities. We are evaluating the accounting, transition, and disclosure requirements of this standard and cannot currently estimate the financial statement impact of adoption. In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815) , to better align an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. The guidance is effective for our fiscal year beginning February 1, 2019 and must be applied using a modified retrospective approach. Early adoption is permitted. We plan to adopt this new standard in the first quarter of our fiscal 2020. We are evaluating the accounting, transition, and disclosure requirements of this standard and cannot currently estimate the financial statement impact of adoption. In February 2018, the FASB issued ASU No. 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income , which provides entities the option to reclassify tax effects stranded in accumulated other comprehensive income as a result of the 2017 Tax Cuts and Jobs Act (the "Tax Act") to retained earnings. The guidance is effective for our fiscal year beginning February 1, 2019 and must be applied either in the period of adoption or retrospectively to each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Act is recognized. Early adoption is permitted. We plan to adopt the new standard in the first quarter of our fiscal 2020 and do not expect it to have a material impact on our condensed consolidated financial statements. In June 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Non-employee Share-Based Payment Accounting , which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees, with certain exceptions. The guidance is effective for our fiscal year beginning February 1, 2019. Early adoption is permitted. We plan to adopt this new standard in the first quarter of our fiscal 2020 and do not expect it to have a material impact on our condensed consolidated financial statements.
Investments	Marketable equity investments consist of money market funds and are included in Cash and cash equivalents on the condensed consolidated balance sheets. We classify our marketable securities as available-for-sale debt securities at the time of purchase and reevaluate such classification as of each balance sheet date. We consider all marketable securities as available for use in current operations, including those with maturity dates beyond one year, and therefore classify these securities as current assets in the accompanying condensed consolidated balance sheets. Marketable securities on the condensed consolidated balance sheets consist of securities with original maturities at the time of purchase greater than three months, and the remainder of the securities is included in Cash and cash equivalents. Non-marketable equity investments consist of investments in privately held companies without readily determinable fair values and are included in Other assets on the condensed consolidated balance sheets.
Fair Value Measurements	We measure our cash equivalents, marketable securities, and foreign currency derivative contracts at fair value at each reporting period using a fair value hierarchy that requires that we maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s classification within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. Three levels of inputs may be used to measure fair value: Level 1 — Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2 — Other inputs that are directly or indirectly observable in the marketplace. Level 3 — Unobservable inputs that are supported by little or no market activity.
Derivatives	Foreign Currency Forward Contracts not Designated as Hedges We also enter into foreign currency forward contracts to hedge a portion of our net outstanding monetary assets and liabilities. These forward contracts are not designated as hedging instruments under applicable accounting guidance, and therefore all changes in the fair value of the forward contracts are recorded in Other income (expense), net on the condensed consolidated statements of operations. These forward contracts are intended to offset the foreign currency gains or losses associated with the underlying monetary assets and liabilities. Cash flows from such forward contracts are classified as operating activities. Our foreign currency contracts are classified within Level 2 of the fair value hierarchy because the valuation inputs are based on quoted prices and market observable data of similar instruments in active markets, such as currency spot and forward rates. Cash Flow Hedges We are exposed to foreign currency fluctuations resulting from customer contracts denominated in foreign currencies. We have a hedging program in which we enter into foreign currency forward contracts related to certain customer contracts. We designate these forward contracts as cash flow hedging instruments as the accounting criteria for such designation have been met. The effective portion of the gains or losses resulting from changes in the fair value of these hedges is recorded in Accumulated other comprehensive income (loss) ("OCI") on the condensed consolidated balance sheets and will be subsequently reclassified to the related revenue line item on the condensed consolidated statements of operations in the same period that the underlying revenues are earned. The changes in value of these contracts resulting from changes in forward points are excluded from the assessment of hedge effectiveness and are recorded as incurred in Other income (expense), net on the condensed consolidated statements of operations. Cash flows from such forward contracts are classified as operating activities.
Convertible Debt	In accounting for the issuance of the Notes, we separated each of the Notes into liability and equity components. The carrying amounts of the liability components were calculated by measuring the fair value of similar liabilities that do not have associated convertible features. The carrying amount of the equity components representing the conversion option were determined by deducting the fair value of the liability components from the par value of the respective Notes. These differences represent debt discounts that are amortized to interest expense over the respective terms of the Notes using the effective interest rate method. The equity components are not remeasured as long as they continue to meet the conditions for equity classification. In accounting for the issuance costs related to the Notes, we allocated the total amount of issuance costs incurred to liability and equity components based on their relative values. Issuance costs attributable to the liability components are being amortized on a straight-line basis, which approximates the effective interest rate method, to interest expense over the respective terms of the Notes. The issuance costs attributable to the equity components were netted against the respective equity components in Additional paid-in capital.
Net Loss Per Share	Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, net of treasury stock. Diluted net loss per share is computed by giving effect to all potential shares of common stock, including our outstanding stock options, outstanding warrants, common stock related to unvested early exercised stock options, common stock related to unvested restricted stock units and awards and convertible senior notes to the extent dilutive, and common stock issuable pursuant to the ESPP. Basic and diluted net loss per share was the same for each period presented, as the inclusion of all potential common shares outstanding would have been anti-dilutive. The net loss per share attributable to common stockholders is allocated based on the contractual participation rights of the Class A common shares and Class B common shares as if the loss for the period had been distributed. As the liquidation and dividend rights are identical, the net loss attributable to common stockholders is allocated on a proportionate basis.

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jul. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Summary of Marketable Securities	At July 31, 2018 , marketable securities consisted of the following (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value U.S. agency obligations $ 283,022 $ — $ (548 ) $ 282,474 U.S. treasury securities 541,060 4 (674 ) 540,390 Corporate bonds 373,800 40 (1,039 ) 372,801 Commercial paper 107,110 — — 107,110 $ 1,304,992 $ 44 $ (2,261 ) $ 1,302,775 Included in cash and cash equivalents $ 11,423 $ — $ — $ 11,423 Included in marketable securities $ 1,293,569 $ 44 $ (2,261 ) $ 1,291,352 At January 31, 2018 , marketable securities consisted of the following (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value U.S. agency obligations $ 683,551 $ — $ (1,127 ) $ 682,424 U.S. treasury securities 797,977 — (1,142 ) 796,835 Corporate bonds 470,259 16 (1,154 ) 469,121 Commercial paper 602,727 — — 602,727 $ 2,554,514 $ 16 $ (3,423 ) $ 2,551,107 Included in cash and cash equivalents $ 417,613 $ — $ (1 ) $ 417,612 Included in marketable securities $ 2,136,901 $ 16 $ (3,422 ) $ 2,133,495
Equity Investments	Equity investments consisted of the following (in thousands): July 31, 2018 January 31, 2018 Marketable equity investments $ 1,451,961 $ 551,804 Non-marketable equity investments 30,405 28,005 $ 1,482,366 $ 579,809

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jul. 31, 2018
Fair Value Disclosures [Abstract]
Information about Assets that are Measured at Fair Value on a Recurring Basis	The following table presents information about our assets and liabilities that are measured at fair value on a recurring basis and their assigned levels within the valuation hierarchy as of July 31, 2018 (in thousands): Description Level 1 Level 2 Level 3 Total U.S. agency obligations $ — $ 282,474 $ — $ 282,474 U.S. treasury securities 540,390 — — 540,390 Corporate bonds — 372,801 — 372,801 Commercial paper — 107,110 — 107,110 Money market funds 1,451,961 — — 1,451,961 Foreign currency derivative assets — 19,173 — 19,173 Total assets $ 1,992,351 $ 781,558 $ — $ 2,773,909 Foreign currency derivative liabilities $ — $ 1,986 $ — $ 1,986 Total liabilities $ — $ 1,986 $ — $ 1,986 The following table presents information about our assets and liabilities that are measured at fair value on a recurring basis and their assigned levels within the valuation hierarchy as of January 31, 2018 (in thousands): Description Level 1 Level 2 Level 3 Total U.S. agency obligations $ — $ 682,424 $ — $ 682,424 U.S. treasury securities 796,835 — — 796,835 Corporate bonds — 469,121 — 469,121 Commercial paper — 602,727 — 602,727 Money market funds 551,804 — — 551,804 Foreign currency derivative assets — 98 — 98 Total assets $ 1,348,639 $ 1,754,370 $ — $ 3,103,009 Foreign currency derivative liabilities $ — $ 32,912 $ — $ 32,912 Total liabilities $ — $ 32,912 $ — $ 32,912
Summary of Carrying Amounts and Estimated Fair Values of Financial Instruments	The following table presents the carrying amounts and estimated fair values of our financial instruments that are not recorded at fair value on the condensed consolidated balance sheets (in thousands): July 31, 2018 January 31, 2018 Net Carrying Amount Estimated Fair Value Net Carrying Amount Estimated Fair Value 0.75% Convertible senior notes $ — $ — $ 341,509 $ 504,994 1.50% Convertible senior notes 226,877 390,623 221,378 385,550 0.25% Convertible senior notes 950,132 1,221,760 928,467 1,200,577

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	6 Months Ended
	Jul. 31, 2018
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): July 31, 2018 January 31, 2018 Land $ 13,199 $ 8,451 Buildings 343,904 255,093 Computers, equipment, and software 474,669 411,177 Computers, equipment, and software acquired under capital leases 11,677 13,848 Furniture and fixtures 35,270 34,809 Leasehold improvements 145,856 132,209 Property and equipment, gross (1) 1,024,575 855,587 Less accumulated depreciation and amortization (346,050 ) (308,978 ) Property and equipment, net $ 678,525 $ 546,609 (1) Property and equipment, gross includes construction-in-progress for owned real estate projects of $244 million and $177 million that have not yet been placed in service as of July 31, 2018 and January 31, 2018 , respectively.

Acquisition-related Intangibl32

Acquisition-related Intangible Assets, Net (Tables)	6 Months Ended
	Jul. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items]
Schedule of Acquired Assets	Acquisition-related intangible assets, net consisted of the following (in thousands): July 31, 2018 January 31, 2018 Acquired developed technology $ 81,800 $ 69,700 Customer relationship assets 1,000 1,000 82,800 70,700 Less accumulated amortization (46,873 ) (36,466 ) Acquisition-related intangible assets, net $ 35,927 $ 34,234
Developed technology and customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	As of July 31, 2018 , our future estimated amortization expense related to acquired developed technology and customer relationship assets is as follows (in thousands): Fiscal Period: 2019 $ 11,770 2020 15,022 2021 5,058 2022 3,400 2023 677 Total $ 35,927

Other Assets (Tables)

Other Assets (Tables)	6 Months Ended
	Jul. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Other Assets	Other assets consisted of the following (in thousands): July 31, 2018 January 31, 2018 Non-marketable equity and other investments $ 32,405 $ 29,205 Prepayments for computing infrastructure platform 9,369 13,588 Technology patents, net 11,396 11,217 Acquired land leasehold interest, net 9,518 9,570 Deposits 4,823 4,492 Net deferred tax assets 2,201 1,884 Other 51,362 39,762 Total $ 121,074 $ 109,718

Derivative Instruments (Tables)

Derivative Instruments (Tables)	6 Months Ended
	Jul. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The fair values of outstanding derivative instruments were as follows (in thousands): Condensed Consolidated Balance Sheets Location July 31, 2018 January 31, 2018 Derivative Assets: Foreign currency forward contracts designated as cash flow hedges Prepaid expenses and other current assets $ 9,717 $ 15 Foreign currency forward contracts designated as cash flow hedges Other assets 9,071 4 Foreign currency forward contracts not designated as hedges Prepaid expenses and other current assets 347 79 Foreign currency forward contracts not designated as hedges Other assets 38 — Total Derivative Assets $ 19,173 $ 98 Derivative Liabilities: Foreign currency forward contracts designated as cash flow hedges Accrued expenses and other current liabilities $ 1,022 $ 18,355 Foreign currency forward contracts designated as cash flow hedges Other liabilities 81 11,650 Foreign currency forward contracts not designated as hedges Accrued expenses and other current liabilities 883 2,805 Foreign currency forward contracts not designated as hedges Other liabilities — 102 Total Derivative Liabilities $ 1,986 $ 32,912
Derivative Instruments, Gain (Loss)	Gains (losses) associated with foreign currency forward contracts designated as cash flow hedges were as follows (in thousands): Condensed Consolidated Statements of Operations and Statements of Comprehensive Loss Locations Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 Gains (losses) recognized in OCI (effective portion) (1) Net change in market value of effective foreign currency forward exchange contracts $ 17,891 $ (22,923 ) $ 36,165 $ (23,898 ) Gains (losses) reclassified from OCI into income (effective portion) Revenues (1,960 ) 473 (3,077 ) 707 Gains (losses) recognized in income (amount excluded from effectiveness testing and ineffective portion) Other income (expense), net 4,027 767 6,258 1,390 (1) Of the total effective portion of foreign currency forward contracts designated as cash flow hedges as of July 31, 2018 , net losses of $6 million are expected to be reclassified out of OCI within the next 12 months. Gains (losses) associated with foreign currency forward contracts not designated as cash flow hedges were as follows (in thousands): Condensed Consolidated Statements of Operations Location Three Months Ended July 31, Six Months Ended July 31, Derivative Type 2018 2017 2018 2017 Foreign currency forward contracts not designated as hedges Other income (expense), net $ 1,884 $ (2,619 ) $ 3,678 $ (2,625 )
Offsetting Assets	As of July 31, 2018 , information related to these offsetting arrangements was as follows (in thousands): Gross Amounts of Recognized Assets Gross Amounts Offset on the Condensed Consolidated Balance Sheets Net Amounts of Assets Presented on the Condensed Consolidated Balance Sheets Gross Amounts Not Offset on the Condensed Consolidated Balance Sheets Net Assets Exposed Financial Instruments Cash Collateral Received Derivative Assets: Counterparty A $ 5,527 $ — $ 5,527 $ (78 ) $ — $ 5,449 Counterparty B 11,340 — 11,340 (1,541 ) — 9,799 Counterparty C 2,306 — 2,306 (367 ) — 1,939 Total $ 19,173 $ — $ 19,173 $ (1,986 ) $ — $ 17,187
Offsetting Liabilities	Gross Amounts of Recognized Liabilities Gross Amounts Offset on the Condensed Consolidated Balance Sheets Net Amounts of Liabilities Presented on the Condensed Consolidated Balance Sheets Gross Amounts Not Offset on the Condensed Consolidated Balance Sheets Net Liabilities Exposed Financial Instruments Cash Collateral Pledged Derivative Liabilities: Counterparty A $ 78 $ — $ 78 $ (78 ) $ — $ — Counterparty B 1,541 — 1,541 (1,541 ) — — Counterparty C 367 — 367 (367 ) — — Total $ 1,986 $ — $ 1,986 $ (1,986 ) $ — $ —

Convertible Senior Notes, Net (

Convertible Senior Notes, Net (Tables)	6 Months Ended
	Jul. 31, 2018
Debt Disclosure [Abstract]
Schedule of Senior Notes	The Notes, net consisted of the following (in thousands): July 31, 2018 January 31, 2018 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes Principal amounts: Principal $ — $ 250,000 $ 1,150,000 $ 350,000 $ 250,000 $ 1,150,000 Unamortized debt discount — (21,806 ) (187,952 ) (7,850 ) (26,968 ) (208,188 ) Unamortized debt issuance costs — (1,317 ) (11,916 ) (641 ) (1,654 ) (13,345 ) Net carrying amount $ — $ 226,877 $ 950,132 $ 341,509 $ 221,378 $ 928,467 Carrying amount of the equity component (1) $ 74,887 $ 66,007 $ 219,702 $ 74,892 $ 66,007 $ 219,702 (1) Included on the condensed consolidated balance sheets within Additional paid-in capital, net of $2 million , $2 million , and $4 million for the 2018 Notes, 2020 Notes, and 2022 Notes, respectively, in equity issuance costs.
Schedule of Interest Expense Recognized Related to Convertible Senior Notes	The following table sets forth total interest expense recognized related to the Notes (in thousands): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes 2018 Notes 2020 Notes 2022 Notes Contractual interest expense $ 540 $ 938 $ 719 $ 657 $ 937 $ — $ 1,196 $ 1,875 $ 1,438 $ 1,313 $ 1,875 $ — Interest cost related to amortization of debt issuance costs 289 169 715 352 167 — 641 337 1,429 704 335 — Interest cost related to amortization of the debt discount 3,567 2,601 10,175 4,104 2,444 — 7,850 5,162 20,236 8,148 4,850 —

Common Stock and Stockholders36

Common Stock and Stockholders' Equity (Tables)	6 Months Ended
	Jul. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Information Related to Restricted Stock Units Activity	A summary of information related to RSU activity during the six months ended July 31, 2018 is as follows: Number of Shares Weighted-Average Grant Date Fair Value Balance as of January 31, 2018 12,819,516 $ 84.77 RSUs granted 5,287,486 125.67 RSUs vested (3,449,505 ) 83.16 RSUs forfeited (460,192 ) 93.29 Balance as of July 31, 2018 14,197,305 $ 100.12
Summary of Information Related to Stock Option Activity	A summary of information related to stock option activity during the six months ended July 31, 2018 is as follows (in millions, except share and per share data): Outstanding Stock Options Weighted- Average Exercise Price Aggregate Intrinsic Value Balance as of January 31, 2018 6,595,486 $ 4.23 $ 763 Stock options granted — — Stock options exercised (751,957 ) 4.64 Stock options canceled (12,000 ) 0.40 Balance as of July 31, 2018 5,831,529 $ 4.19 $ 699 Vested as of July 31, 2018 5,831,529 $ 4.19 $ 699 Exercisable as of July 31, 2018 5,831,529 $ 4.19 $ 699

Other Income (Expense), Net (Ta

Other Income (Expense), Net (Tables)	6 Months Ended
	Jul. 31, 2018
Other Income and Expenses [Abstract]
Other Income (Expense), Net	Other income (expense), net consisted of the following (in thousands): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 Interest income $ 14,692 $ 5,051 $ 26,928 $ 9,080 Interest expense (1) (17,515 ) (6,840 ) (35,817 ) (13,826 ) Other income (expense) 4,436 2,727 6,654 4,021 Other income (expense), net $ 1,613 $ 938 $ (2,235 ) $ (725 ) (1) Interest expense includes the contractual interest expense related to the 2018 Notes, 2020 Notes, and 2022 Notes and non-cash interest expense related to amortization of the debt discount and debt issuance costs, net of capitalized interest costs (see Note 10).

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	6 Months Ended
	Jul. 31, 2018
Earnings Per Share [Abstract]
Summary of Calculation of Basic and Diluted Net Loss Per Share	The following table presents the calculation of basic and diluted net loss attributable to common stockholders per share (in thousands, except per share data): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 Class A Class B Class A Class B Class A Class B Class A Class B Net loss per share, basic and diluted: Numerator: Allocation of distributed net loss $ (58,776 ) $ (27,380 ) $ (52,997 ) $ (29,535 ) $ (108,888 ) $ (51,678 ) $ (93,625 ) $ (52,951 ) Denominator: Weighted-average common shares outstanding 147,310 68,622 132,940 74,088 145,475 69,042 131,232 74,221 Basic and diluted net loss per share $ (0.40 ) $ (0.40 ) $ (0.40 ) $ (0.40 ) $ (0.75 ) $ (0.75 ) $ (0.71 ) $ (0.71 )
Shares Excluded from Diluted Loss Per Share	The anti-dilutive securities excluded from the weighted-average shares used to calculate the diluted net loss per common share were as follows (in thousands): As of July 31, 2018 2017 Outstanding common stock options 5,832 7,502 Shares subject to repurchase — 30 Unvested restricted stock awards, units, and PRSUs 14,629 14,414 Shares related to the convertible senior notes 15,079 7,261 Shares subject to warrants related to the issuance of convertible senior notes 15,079 7,261 Shares issuable pursuant to the ESPP 418 375 51,037 36,843

Geographic Information (Tables)

Geographic Information (Tables)	6 Months Ended
	Jul. 31, 2018
Segment Reporting [Abstract]
Summary of Revenues by Geographic Area	The following table sets forth revenue by geographic area (in thousands): Three Months Ended July 31, Six Months Ended July 31, 2018 2017 2018 2017 United States $ 515,257 $ 419,466 $ 995,339 $ 802,637 Other countries 156,463 105,854 295,024 202,544 Total $ 671,720 $ 525,320 $ 1,290,363 $ 1,005,181
Long-lived Assets by Geographic Areas	The following table sets forth Property and equipment, net by geographic area (in thousands): July 31, 2018 January 31, 2018 United States $ 607,975 $ 479,996 Ireland 55,973 52,904 Other countries 14,577 13,709 Total $ 678,525 $ 546,609

Overview and Basis of Present40

Overview and Basis of Presentation (Detail)	6 Months Ended
	Jul. 31, 2018segment
Accounting Policies [Abstract]
Number of operating segments	1

Accounting Standards - Recently

Accounting Standards - Recently Adopted Accounting Pronouncements (Details) $ in Millions	Feb. 01, 2018USD ($)
Retained Earnings | Accounting Standards Update 2016-16
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of new accounting principle in period of adoption	$ 0.4

Investments - Summary of Market

Investments - Summary of Marketable Securities (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,304,992	$ 2,554,514
Unrealized Gains	44	16
Unrealized Losses	(2,261)	(3,423)
Aggregate Fair Value	1,302,775	2,551,107
U.S. agency obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	283,022	683,551
Unrealized Gains	0	0
Unrealized Losses	(548)	(1,127)
Aggregate Fair Value	282,474	682,424
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	541,060	797,977
Unrealized Gains	4	0
Unrealized Losses	(674)	(1,142)
Aggregate Fair Value	540,390	796,835
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	373,800	470,259
Unrealized Gains	40	16
Unrealized Losses	(1,039)	(1,154)
Aggregate Fair Value	372,801	469,121
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	107,110	602,727
Unrealized Gains	0	0
Unrealized Losses	0	0
Aggregate Fair Value	107,110	602,727
Included in cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	11,423	417,613
Unrealized Gains	0	0
Unrealized Losses	0	(1)
Aggregate Fair Value	11,423	417,612
Included in marketable securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,293,569	2,136,901
Unrealized Gains	44	16
Unrealized Losses	(2,261)	(3,422)
Aggregate Fair Value	$ 1,291,352	$ 2,133,495

Investments (Detail)

Investments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Proceeds of sale of marketable securities	$ 914,938	$ 180,863	$ 942,297	$ 189,937

Investments - Equity Investment

Investments - Equity Investments (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Marketable equity investments	$ 1,451,961	$ 551,804
Non-marketable equity investments	30,405	28,005
Marketable and Non-Marketable Equity Investments	$ 1,482,366	$ 579,809

Fair Value Measurements - Infor

Fair Value Measurements - Information about Assets that are Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$ 2,773,909	$ 3,103,009
Total liabilities	1,986	32,912
U.S. agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	282,474	682,424
U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	540,390	796,835
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	372,801	469,121
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	107,110	602,727
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,451,961	551,804
Foreign currency derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	19,173	98
Foreign currency derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities	1,986	32,912
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,992,351	1,348,639
Total liabilities	0	0
Level 1 | U.S. agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 1 | U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	540,390	796,835
Level 1 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 1 | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 1 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,451,961	551,804
Level 1 | Foreign currency derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 1 | Foreign currency derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	781,558	1,754,370
Total liabilities	1,986	32,912
Level 2 | U.S. agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	282,474	682,424
Level 2 | U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 2 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	372,801	469,121
Level 2 | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	107,110	602,727
Level 2 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 2 | Foreign currency derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	19,173	98
Level 2 | Foreign currency derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities	1,986	32,912
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Total liabilities	0	0
Level 3 | U.S. agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 3 | U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 3 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 3 | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 3 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 3 | Foreign currency derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Level 3 | Foreign currency derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities	$ 0	$ 0

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Carrying Amounts and Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018	Sep. 30, 2017	Jun. 30, 2013
0.75% Convertible senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net Carrying Amount	$ 0	$ 341,509
Estimated Fair Value	$ 0	504,994
Contractual interest rate	0.75%			0.75%
1.50% Convertible senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net Carrying Amount	$ 226,877	221,378
Estimated Fair Value	$ 390,623	385,550
Contractual interest rate	1.50%			1.50%
0.25% Convertible senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net Carrying Amount	$ 950,132	928,467
Estimated Fair Value	$ 1,221,760	$ 1,200,577
Contractual interest rate	0.25%		0.25%

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Detail) - USD ($)	6 Months Ended
	Jul. 31, 2018	Jan. 31, 2018	Sep. 30, 2017	Jun. 30, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Closing price of company's common stock, dollars per share	$ 124.02
0.75% Convertible senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes, principal amount	$ 0	$ 350,000,000		$ 350,000,000
Contractual interest rate	0.75%			0.75%
If-converted value in excess of principal
1.50% Convertible senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes, principal amount	$ 250,000,000	$ 250,000,000		$ 250,000,000
Contractual interest rate	1.50%			1.50%
If-converted value in excess of principal	$ 129,000,000
0.25% Convertible senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes, principal amount			$ 1,150,000,000
Contractual interest rate	0.25%		0.25%
If-converted value less than principal	$ 180,000,000

Deferred Costs (Detail)

Deferred Costs (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017	Jan. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred sales commissions	$ 207,000		$ 207,000		$ 204,000
Amortization of deferred costs	$ 17,061	$ 14,009	$ 33,421	$ 27,646

Property and Equipment, Net - S

Property and Equipment, Net - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,024,575	$ 855,587
Less accumulated depreciation and amortization	(346,050)	(308,978)
Property and equipment, net	678,525	546,609
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	13,199	8,451
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross	343,904	255,093
Computers, equipment, and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	474,669	411,177
Computers, equipment, and software acquired under capital leases
Property, Plant and Equipment [Line Items]
Property and equipment, gross	11,677	13,848
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	35,270	34,809
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	145,856	132,209
Construction in Progress Related to Owned Real Estate Projects
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 244,000	$ 177,000

Property and Equipment, Net (De

Property and Equipment, Net (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 36	$ 28	$ 69	$ 55
Interest costs capitalized to property and equipment	$ 2	$ 2	$ 4	$ 3

Acquisition-related Intangibl51

Acquisition-related Intangible Assets, Net - Schedule of Acquired Assets (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018USD ($)acquistion	Jul. 31, 2017USD ($)	Jul. 31, 2018USD ($)	Jul. 31, 2017USD ($)	Jan. 31, 2018USD ($)
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 82,800		$ 82,800		$ 70,700
Less accumulated amortization	(46,873)		(46,873)		(36,466)
Acquisition-related intangible assets, net	$ 35,927		35,927		34,234
Number of acquisitions | acquistion	2
Increase in goodwill	$ 16,000
Acquired developed technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	81,800		81,800		69,700
Increase in intangible assets	12,000
Customer relationship assets
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	1,000		1,000		$ 1,000
Developed technology and customer relationships
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 5,000	$ 5,000	$ 10,000	$ 10,000

Acquisition-related Intangibl52

Acquisition-related Intangible Assets, Net - Schedule of Future Amortization Expense (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Finite-Lived Intangible Assets, Net, Amortization Expense, Rolling Maturity [Abstract]
Total	$ 11,396	$ 11,217
Acquired developed technology and customer relationship assets
Finite-Lived Intangible Assets, Net, Amortization Expense, Rolling Maturity [Abstract]
2,019	11,770
2,020	15,022
2,021	5,058
2,022	3,400
2,023	677
Total	$ 35,927

Other Assets - Schedule of Othe

Other Assets - Schedule of Other Assets (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018	Jan. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Non-marketable equity and other investments	$ 32,405	$ 29,205
Prepayments for computing infrastructure platform	9,369	13,588	$ 2,000
Technology patents, net	11,396	11,217
Acquired land leasehold interest, net	9,518	9,570
Deposits	4,823	4,492
Net deferred tax assets	2,201	1,884
Other	51,362	39,762
Total	$ 121,074	$ 109,718

Derivative Instruments (Detail)

Derivative Instruments (Detail) - Forward Contracts - USD ($) $ in Millions	6 Months Ended
	Jul. 31, 2018	Jan. 31, 2018
Designated as Hedging Instrument
Derivative [Line Items]
Derivative, notional amount	$ 655	$ 549
Designated as Hedging Instrument | Maximum
Derivative [Line Items]
Derivative, remaining maturity	36 months
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, notional amount	$ 201	$ 75

Derivative Instruments - Fair V

Derivative Instruments - Fair Values of Outstanding Derivative Instruments (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 19,173	$ 98
Derivative Liabilities	1,986	32,912
Forward Contracts | Designated as Hedging Instrument | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	9,717	15
Forward Contracts | Designated as Hedging Instrument | Other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	9,071	4
Forward Contracts | Designated as Hedging Instrument | Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	1,022	18,355
Forward Contracts | Designated as Hedging Instrument | Other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	81	11,650
Forward Contracts | Not Designated as Hedging Instrument | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	347	79
Forward Contracts | Not Designated as Hedging Instrument | Other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	38	0
Forward Contracts | Not Designated as Hedging Instrument | Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	883	2,805
Forward Contracts | Not Designated as Hedging Instrument | Other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	$ 0	$ 102

Derivative Instruments - Gains

Derivative Instruments - Gains (losses) Associated with Foreign Currency Forward Contracts (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from OCI into income (effective portion)	$ 17,370	$ (23,396)	$ 34,337	$ (24,605)
Derivative instruments, gain (loss) expected to be reclassified from accumulated OCI within the next 12 months			(6,000)
Other income (expense), net
Derivative Instruments, Gain (Loss) [Line Items]
Foreign currency forward contracts not designated as hedges	1,884	(2,619)	3,678	(2,625)
Designated as Hedging Instrument | Revenues
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from OCI into income (effective portion)	(1,960)	473	(3,077)	707
Designated as Hedging Instrument | Other income (expense), net
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in income (amount excluded from effectiveness testing and ineffective portion)	4,027	767	6,258	1,390
Designated as Hedging Instrument | Net change in market value of effective foreign currency forward exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in OCI (effective portion)	$ 17,891	$ (22,923)	$ 36,165	$ (23,898)

Derivative Instruments - Offset

Derivative Instruments - Offsetting Assets (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	$ 19,173	$ 98
Gross Amounts Offset on the Condensed Consolidated Balance Sheets	0
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheets	19,173
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(1,986)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Received	0
Net Assets Exposed	17,187
Counterparty A
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	5,527
Gross Amounts Offset on the Condensed Consolidated Balance Sheets	0
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheets	5,527
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(78)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Received	0
Net Assets Exposed	5,449
Counterparty B
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	11,340
Gross Amounts Offset on the Condensed Consolidated Balance Sheets	0
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheets	11,340
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(1,541)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Received	0
Net Assets Exposed	9,799
Counterparty C
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	2,306
Gross Amounts Offset on the Condensed Consolidated Balance Sheets	0
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheets	2,306
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(367)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Received	0
Net Assets Exposed	$ 1,939

Derivative Instruments - Offs58

Derivative Instruments - Offsetting Liabilities (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	$ 1,986	$ 32,912
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheets	1,986
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(1,986)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Pledged	0
Net Liabilities Exposed	0
Counterparty A
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	78
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheets	78
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(78)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Pledged	0
Net Liabilities Exposed	0
Counterparty B
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	1,541
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheets	1,541
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(1,541)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Pledged	0
Net Liabilities Exposed	0
Counterparty C
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	367
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheets	367
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Financial Instruments	(367)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Cash Collateral Pledged	0
Net Liabilities Exposed	$ 0

Convertible Senior Notes, Net59

Convertible Senior Notes, Net (Detail) $ / shares in Units, shares in Millions	3 Months Ended		6 Months Ended
	Jul. 31, 2018USD ($)$ / sharesshares	Jul. 31, 2017USD ($)	Jul. 31, 2018USD ($)trading_dayday$ / sharesshares	Jul. 31, 2017USD ($)	Jan. 31, 2018USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2013USD ($)
Debt Instrument [Line Items]
Threshold consecutive trading days | trading_day			30
Number of days out of 30 that common stock price exceeded conversion price (in days) | day			20
Capitalized interest costs	$ 2,000,000	$ 2,000,000	$ 4,000,000	$ 3,000,000
2018 Notes
Debt Instrument [Line Items]
Contractual interest rate	0.75%		0.75%				0.75%
Convertible senior notes, principal amount	$ 0		$ 0		$ 350,000,000		$ 350,000,000
Repayments of debt	350,000,000
Liability issuance costs	7,000,000		7,000,000
Equity issuance costs			2,000,000
Amortization expense for liability issuance costs	$ 289,000	352,000	$ 641,000	704,000
Effective interest rates of the liability components	5.75%		5.75%
2020 Notes
Debt Instrument [Line Items]
Contractual interest rate	1.50%		1.50%				1.50%
Convertible senior notes, principal amount	$ 250,000,000		$ 250,000,000		$ 250,000,000		$ 250,000,000
Threshold percentage of conversion price			130.00%
Liability issuance costs	5,000,000		$ 5,000,000
Equity issuance costs			2,000,000
Amortization expense for liability issuance costs	$ 169,000	167,000	$ 337,000	335,000
Remaining life of the Notes			23 months
Effective interest rates of the liability components	6.25%		6.25%
2022 Notes
Debt Instrument [Line Items]
Contractual interest rate	0.25%		0.25%			0.25%
Convertible senior notes, principal amount						$ 1,150,000,000
Liability issuance costs	$ 14,000,000		$ 14,000,000
Equity issuance costs			4,000,000
Amortization expense for liability issuance costs	$ 715,000	$ 0	$ 1,429,000	$ 0
Remaining life of the Notes			50 months
Effective interest rates of the liability components	4.60%		4.60%
Aggregate amount for purchased options	$ 176,000,000		$ 176,000,000
Proceeds from sale of warrants			$ 81,000,000
Shares related to the convertible senior notes
Debt Instrument [Line Items]
Repurchase of notes percentage			100.00%
2018 and 2020 Notes
Debt Instrument [Line Items]
Aggregate amount for purchased options	$ 144,000,000		$ 144,000,000
Proceeds from sale of warrants			$ 93,000,000
Warrants expires in October 2018
Debt Instrument [Line Items]
Shares covered by each purchased options or warrants (in shares) | shares	4.2		4.2
Number of trading days over			60 days
Exercise price of warrants (in dollars per share) | $ / shares	$ 107.96		$ 107.96
Warrants expires in October 2020
Debt Instrument [Line Items]
Shares covered by each purchased options or warrants (in shares) | shares	3.1		3.1
Number of trading days over			60 days
Exercise price of warrants (in dollars per share) | $ / shares	$ 107.96		$ 107.96
Warrants Expires In January 2023
Debt Instrument [Line Items]
Shares covered by each purchased options or warrants (in shares) | shares	7.8		7.8
Number of trading days over			60 days
Exercise price of warrants (in dollars per share) | $ / shares	$ 213.96		$ 213.96
Class A | 2018 Notes
Debt Instrument [Line Items]
Stock Issued During Period, Shares, New Issues | shares	1.5
Initial conversion price (in dollars per share) | $ / shares	$ 83.28		$ 83.28
Debt conversion, shares issued | shares	1.5		4.2
Class A | 2020 Notes
Debt Instrument [Line Items]
Initial conversion rate			12.2340
Principal amount converted into Class A Common Stock			$ 1,000
Initial conversion price (in dollars per share) | $ / shares	$ 81.74		$ 81.74
Debt conversion, shares issued | shares			3.1
Class A | 2022 Notes
Debt Instrument [Line Items]
Initial conversion rate			6.7982
Principal amount converted into Class A Common Stock			$ 1,000
Initial conversion price (in dollars per share) | $ / shares	$ 147.10		$ 147.10
Debt conversion, shares issued | shares			7.8
Debt Conversion, Option One | Shares related to the convertible senior notes
Debt Instrument [Line Items]
Threshold trading days (in trading days) | trading_day			20
Threshold consecutive trading days | trading_day			30
Threshold percentage of conversion price			130.00%
Debt Conversion, Option Two | Shares related to the convertible senior notes
Debt Instrument [Line Items]
Threshold trading days (in trading days) | trading_day			5
Debt Conversion, Option Two | Shares related to the convertible senior notes | Maximum
Debt Instrument [Line Items]
Threshold percentage of conversion price			98.00%

Convertible Senior Notes, Net -

Convertible Senior Notes, Net - Schedule of Senior Notes (Detail) - USD ($)	6 Months Ended
	Jul. 31, 2018	Jan. 31, 2018	Jun. 30, 2013
Convertible Debt [Abstract]
Net carrying amount, current	$ 226,877,000	$ 341,509,000
Net carrying amount, non-current	950,132,000	1,149,845,000
2018 Notes
Convertible Debt [Abstract]
Principal	0	350,000,000	$ 350,000,000
Unamortized debt discount	0	(7,850,000)
Unamortized debt issuance costs	0	(641,000)
Net carrying amount, current	0	341,509,000
Carrying amount of the equity component	74,887,000	74,892,000
Equity issuance costs	2,000,000
2020 Notes
Convertible Debt [Abstract]
Principal	250,000,000	250,000,000	$ 250,000,000
Unamortized debt discount	(21,806,000)	(26,968,000)
Unamortized debt issuance costs	(1,317,000)	(1,654,000)
Net carrying amount, current	226,877,000
Net carrying amount, non-current		221,378,000
Carrying amount of the equity component	66,007,000	66,007,000
Equity issuance costs	2,000,000
2022 Notes
Convertible Debt [Abstract]
Principal	1,150,000,000	1,150,000,000
Unamortized debt discount	(187,952,000)	(208,188,000)
Unamortized debt issuance costs	(11,916,000)	(13,345,000)
Net carrying amount, non-current	950,132,000	928,467,000
Carrying amount of the equity component	$ 219,702,000	$ 219,702,000

Convertible Senior Notes, Net61

Convertible Senior Notes, Net - Schedule of Interest Expense Recognized Related to Convertible Senior Notes (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
2018 Notes
Debt Instrument [Line Items]
Contractual interest expense	$ 540	$ 657	$ 1,196	$ 1,313
Interest cost related to amortization of debt issuance costs	289	352	641	704
Interest cost related to amortization of the debt discount	3,567	4,104	7,850	8,148
2020 Notes
Debt Instrument [Line Items]
Contractual interest expense	938	937	1,875	1,875
Interest cost related to amortization of debt issuance costs	169	167	337	335
Interest cost related to amortization of the debt discount	2,601	2,444	5,162	4,850
2022 Notes
Debt Instrument [Line Items]
Contractual interest expense	719	0	1,438	0
Interest cost related to amortization of debt issuance costs	715	0	1,429	0
Interest cost related to amortization of the debt discount	$ 10,175	$ 0	$ 20,236	$ 0

Commitments and Contingencies (

Commitments and Contingencies (Detail) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Jan. 31, 2014USD ($)a	Jul. 31, 2018USD ($)	Jul. 31, 2017USD ($)	Jul. 31, 2018USD ($)	Jul. 31, 2017USD ($)	Jan. 31, 2018USD ($)
Commitments and Contingencies Disclosure [Abstract]
Rent expense		$ 24,000	$ 20,000	$ 47,000	$ 39,000
Lease term period	95 years
Parcel of vacant land (in acres) | a	6.9
Prepayments for computing infrastructure platform	$ 2,000	$ 9,369		9,369		$ 13,588
Annual rent payments plus increases based on increases in consumer price index				$ 200

Common Stock and Stockholders63

Common Stock and Stockholders' Equity - Additional Information (Detail) shares in Millions, $ in Billions	1 Months Ended	6 Months Ended
	Mar. 31, 2018shares	Jul. 31, 2018USD ($)vote / sharesshares
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		5 years
Period of which options become exercisable		10 years
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		4 years
Unrecognized compensation cost - other than options | $		$ 1.3
Unrecognized compensation cost recognized over weighted-average period		3 years
Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, outstanding (in shares)		149
Common stock, votes per share | vote / shares		1
Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, outstanding (in shares)		68
Common stock, votes per share | vote / shares		10
2012 Equity Incentive Plan | Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share reserve increased (in shares)	11
Common stock available for future grants (in shares)		66
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value of stock at which employees are granted shares		85.00%
Common stock available for future grants (in shares)		7

Common Stock and Stockholders64

Common Stock and Stockholders' Equity - Restricted Stock Units Activity (Detail) - Restricted Stock Units	6 Months Ended
	Jul. 31, 2018$ / sharesshares
Restricted Stock Units
Beginning Balance, Number of Shares | shares	12,819,516
RSUs granted, Number of Shares | shares	5,287,486
RSUs vested, Number of Shares | shares	(3,449,505)
RSUs forfeited, Number of Shares | shares	(460,192)
Ending Balance, Number of Shares | shares	14,197,305
Weighted-Average Grant Date Fair Value
Beginning Balance (in dollars per share) | $ / shares	$ 84.77
RSUs granted (in dollars per share) | $ / shares	125.67
RSUs vested (in dollars per share) | $ / shares	83.16
RSUs forfeited (in dollars per share) | $ / shares	93.29
Ending Balance (in dollars per share) | $ / shares	$ 100.12

Common Stock and Stockholders65

Common Stock and Stockholders' Equity - PRSU's (Detail) - All Other Employees - Performance Based Restricted Stock Unit PRSU shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
	Jul. 31, 2018USD ($)shares	Jul. 31, 2018USD ($)shares
Vesting March 15 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs granted, number of Shares | shares		0.4
Compensation related cost		$ 7
Vesting March 15 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs granted, number of Shares | shares	0.4
Compensation related cost		9
Unrecognized compensation cost - other than options	$ 45	$ 45
Unrecognized compensation cost recognized over weighted-average period		7 months

Common Stock and Stockholders66

Common Stock and Stockholders' Equity - Stock Options (Detail) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jul. 31, 2018	Jan. 31, 2018
Outstanding Stock Options
Beginning Balance (in shares)	6,595,486
Stock options granted (in shares)	0
Stock options exercised (in shares)	(751,957)
Stock options canceled (in shares)	(12,000)
Ending Balance (in shares)	5,831,529
Vested (in shares)	5,831,529
Exercisable (in shares)	5,831,529
Weighted- Average Exercise Price
Beginning Balance (in dollars per share)	$ 4.23
Stock option grants (in dollars per share)	0
Stock options exercised (in dollars per share)	4.64
Stock options canceled (in dollars per share)	0.40
Ending Balance (in dollars per share)	4.19
Vested, Weighted-Average Exercise Price (in dollars per share)	4.19
Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 4.19
Aggregate Intrinsic Value (in millions)	$ 699	$ 763
Vested, Aggregate Intrinsic Value	699
Exercisable, Aggregate Intrinsic Value	$ 699

Unearned Revenue and Performa67

Unearned Revenue and Performance Obligations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Revenue from Contract with Customer [Abstract]
Subscription revenue recognized that was included in total unearned revenue balance at beginning of period	$ 507	$ 398	$ 899	$ 673
Revenue is expected to be recognized from remaining performance obligations for subscription contracts	$ 5,500		$ 5,500
Recognition period	24 months		24 months

Other Income (Expense), Net (De

Other Income (Expense), Net (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Other Income and Expenses [Abstract]
Interest income	$ 14,692	$ 5,051	$ 26,928	$ 9,080
Interest expense	(17,515)	(6,840)	(35,817)	(13,826)
Other income (expense)	4,436	2,727	6,654	4,021
Other income (expense), net	$ 1,613	$ 938	$ (2,235)	$ (725)

Income Taxes (Detail)

Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Income Tax Disclosure [Abstract]
Provision for (benefit from) income taxes	$ (1,213)	$ 1,841	$ (1,915)	$ 4,022

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Calculation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Denominator:
Weighted-average common shares outstanding (in shares)	215,932	207,028	214,517	205,453
Basic and diluted net loss per share (in dollars per share)	$ (0.40)	$ (0.40)	$ (0.75)	$ (0.71)
Class A
Numerator:
Allocation of distributed net loss	$ (58,776)	$ (52,997)	$ (108,888)	$ (93,625)
Denominator:
Weighted-average common shares outstanding (in shares)	147,310	132,940	145,475	131,232
Basic and diluted net loss per share (in dollars per share)	$ (0.40)	$ (0.40)	$ (0.75)	$ (0.71)
Class B
Numerator:
Allocation of distributed net loss	$ (27,380)	$ (29,535)	$ (51,678)	$ (52,951)
Denominator:
Weighted-average common shares outstanding (in shares)	68,622	74,088	69,042	74,221
Basic and diluted net loss per share (in dollars per share)	$ (0.40)	$ (0.40)	$ (0.75)	$ (0.71)

Net Loss Per Share - Summary 71

Net Loss Per Share - Summary of Diluted Net Loss Per Common Share (Detail) - shares shares in Thousands	6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities (in shares)	51,037	36,843
Outstanding common stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities (in shares)	5,832	7,502
Shares subject to repurchase
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities (in shares)	0	30
Unvested restricted stock awards, units, and PRSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities (in shares)	14,629	14,414
Shares related to the convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities (in shares)	15,079	7,261
Shares subject to warrants related to the issuance of convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities (in shares)	15,079	7,261
Shares issuable pursuant to the ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities (in shares)	418	375

Related Party Transactions (Det

Related Party Transactions (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017	Jan. 31, 2014
Related Party Transaction [Line Items]
Term of agreements (in years)					95 years
Chairman, Mr. Duffield
Related Party Transaction [Line Items]
Term of agreements (in years)	9 years		9 years
Rent expense	$ 2	$ 2	$ 5	$ 4

Geographic Information Summary

Geographic Information Summary of Revenues by Geographic Area (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018USD ($)market	Jul. 31, 2017USD ($)	Jul. 31, 2018USD ($)market	Jul. 31, 2017USD ($)
Disaggregation of Revenue [Line Items]
Number of primary geographical markets | market	2		2
Revenue	$ 671,720	$ 525,320	$ 1,290,363	$ 1,005,181
United States
Disaggregation of Revenue [Line Items]
Revenue	515,257	419,466	995,339	802,637
Other countries
Disaggregation of Revenue [Line Items]
Revenue	$ 156,463	$ 105,854	$ 295,024	$ 202,544

Geographic Information - Long-L

Geographic Information - Long-Lived Assets (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 678,525	$ 546,609
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	607,975	479,996
Ireland
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	55,973	52,904
Other countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 14,577	$ 13,709

Subsequent Events (Details)

Subsequent Events (Details) $ in Billions	Aug. 01, 2018USD ($)
Subsequent Event
Subsequent Event [Line Items]
Consideration paid for acquisition	$ 1.5