Ellie Mae (ELLI) 10-K 1 Mar 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 22, 2018	Jun. 30, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	ELLIE MAE INC
Entity Central Index Key	1,122,388
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Amendment Flag	false
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		34,289,833
Entity Well-known Seasoned Issuer	Yes
Entity Public Float			$ 2,325,501,000
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 137,698	$ 380,907
Short-term investments	103,345	41,841
Accounts receivable, net of allowance for doubtful accounts of $340 and $45 as of December 31, 2017 and December 31, 2016, respectively	43,121	39,358
Prepaid expenses and other current assets	18,474	15,209
Total current assets	302,638	477,315
Property and equipment, net	186,991	126,297
Long-term investments	107,363	45,931
Intangible assets, net	80,874	17,289
Deposits and other assets	9,290	10,138
Goodwill	144,451	74,547
Total assets	831,607	751,517
Current liabilities:
Accounts payable	24,913	15,942
Accrued and other current liabilities	26,188	39,809
Deferred revenue	26,287	23,126
Total current liabilities	77,388	78,877
Other long-term liabilities	18,880	17,732
Total liabilities	96,268	96,609
Commitments and contingencies (Note 9)
Stockholders’ equity:
Common stock, $0.0001 par value per share; 140,000,000 authorized shares, 34,227,684 and 33,685,649 shares issued and outstanding as of December 31, 2017 and December 31, 2016, respectively	3	3
Additional paid-in capital	649,817	612,098
Accumulated other comprehensive loss	(880)	(219)
Retained earnings	86,399	43,026
Total stockholders’ equity	735,339	654,908
Total liabilities and stockholders’ equity	$ 831,607	$ 751,517

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowances for doubtful accounts	$ 340	$ 45
Common stock, par value	$ 0.0001000	$ 0.0001000
Common stock, shares authorized	140,000,000	140,000,000
Common stock, shares issued	34,227,684	33,685,649
Common stock, shares outstanding	34,227,684	33,685,649

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Revenues	$ 417,042,000	$ 360,285,000	$ 253,937,000
Cost of revenues	160,910,000	120,145,000	84,208,000
Gross profit	256,132,000	240,140,000	169,729,000
Operating expenses:
Sales and marketing	65,042,000	54,704,000	38,208,000
Research and development	69,266,000	58,501,000	40,451,000
General and administrative	79,686,000	71,318,000	57,212,000
Total operating expenses	213,994,000	184,523,000	135,871,000
Income from operations	42,138,000	55,617,000	33,858,000
Other income, net	3,256,000	989,000	619,000
Income before income taxes	45,394,000	56,606,000	34,477,000
Income tax provision (benefit)	(7,456,000)	18,830,000	12,219,000
Net income	$ 52,850,000	$ 37,776,000	$ 22,258,000
Net income per share of common stock:
Basic (USD per share)	$ 1.55	$ 1.21	$ 0.76
Diluted (USD per share)	$ 1.48	$ 1.15	$ 0.72
Weighted average common shares used in computing net income per share of common stock:
Basic (in shares)	34,056,962	31,179,857	29,179,352
Diluted (in shares)	35,805,524	32,799,785	30,842,584
Comprehensive income, net of taxes:
Net income	$ 52,850,000	$ 37,776,000	$ 22,258,000
Unrealized gain (loss) on investments	(661,000)	38,000	(162,000)
Comprehensive income	$ 52,189,000	$ 37,814,000	$ 22,096,000

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]
Balances, shares at Dec. 31, 2014		28,907,147
Balances at Dec. 31, 2014	$ 252,884,000	$ 3,000	$ 242,527,000	$ (95,000)	$ 10,449,000
Issuance of common stock under stock incentive plans, shares		1,109,013
Issuance of common stock under stock incentive plans	10,094,000		10,094,000
Shares withheld for employee taxes related to vested restricted stock units, shares		(56,797)
Shares withheld for employee taxes related to vested restricted stock units	(3,552,000)		(3,552,000)
Issuance of common stock under employee stock purchase plan, shares		110,598
Issuance of common stock under employee stock purchase plan	4,105,000		4,105,000
Stock-based compensation expense	$ 25,367,000		25,367,000
Excess tax benefit from exercise of stock options			11,387,000
Stock repurchase, shares	(503,450)	(503,450)
Stock repurchase	$ (31,530,000)		(4,586,000)		(26,944,000)
Unrealized gain (loss) on investments	(162,000)			(162,000)
Net income	22,258,000				22,258,000
Balances, shares at Dec. 31, 2015		29,566,511
Balances at Dec. 31, 2015	290,851,000	$ 3,000	285,342,000	(257,000)	5,763,000
Issuance of common stock under stock incentive plans, shares		934,234
Issuance of common stock under stock incentive plans	10,573,000		10,573,000
Issuance of common stock in public offering, net of issuance costs, shares		3,162,500
Issuance of common stock in public offering, net of issuance costs	271,309,000		271,309,000
Shares withheld for employee taxes related to vested restricted stock units, shares		(71,079)
Shares withheld for employee taxes related to vested restricted stock units	(5,976,000)		(5,976,000)
Issuance of common stock under employee stock purchase plan, shares		101,816
Issuance of common stock under employee stock purchase plan	6,724,000		6,724,000
Stock-based compensation expense	34,302,000		34,302,000
Excess tax benefit from exercise of stock options	$ 11,387,000		9,974,000
Stock repurchase, shares	(8,333)	(8,333)
Stock repurchase	$ (663,000)		(150,000)		(513,000)
Unrealized gain (loss) on investments	38,000			38,000
Net income	37,776,000				37,776,000
Balances, shares at Dec. 31, 2016		33,685,649
Balances at Dec. 31, 2016	654,908,000	$ 3,000	612,098,000	(219,000)	43,026,000
Issuance of common stock under stock incentive plans, shares		961,448
Issuance of common stock under stock incentive plans	10,208,000		10,208,000
Shares withheld for employee taxes related to vested restricted stock units, shares		(139,235)
Shares withheld for employee taxes related to vested restricted stock units	(13,826,000)		(13,826,000)
Issuance of common stock under employee stock purchase plan, shares		121,010
Issuance of common stock under employee stock purchase plan	9,098,000		9,098,000
Stock-based compensation expense	39,762,000		39,762,000
Excess tax benefit from exercise of stock options	$ 9,974,000
Stock repurchase, shares	(401,188)	(401,188)
Stock repurchase	$ (35,244,000)		(7,523,000)		(27,721,000)
Excess tax benefits cumulative-effect adjustment resulting from the adoption of ASU 2016-09 (Note 2)	18,244,000				18,244,000
Unrealized gain (loss) on investments	(661,000)			(661,000)
Net income	52,850,000				52,850,000
Balances, shares at Dec. 31, 2017		34,227,684
Balances at Dec. 31, 2017	$ 735,339,000	$ 3,000	$ 649,817,000	$ (880,000)	$ 86,399,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 52,850,000	$ 37,776,000	$ 22,258,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	36,482,000	20,460,000	10,842,000
Amortization of intangible assets	9,515,000	5,521,000	5,180,000
Impairment loss on intangible assets	0	0	562,000
Legal settlement	0	0	(522,000)
Stock-based compensation expense	34,467,000	31,471,000	24,241,000
Impairment and loss on sale of property and equipment	0	5,000
Impairment and loss on sale of property and equipment			97,000
Deferred income taxes	(7,849,000)	7,784,000	2,255,000
Amortization (accretion) of investments	(1,704,000)	1,024,000	1,033,000
Changes in operating assets and liabilities:
Accounts receivable, net	(997,000)	(10,791,000)	(7,943,000)
Prepaid expenses and other current assets	(2,622,000)	(5,334,000)	1,381,000
Deposits and other assets	1,088,000	(3,464,000)	(1,985,000)
Accounts payable	4,943,000	3,678,000	290,000
Accrued, other current and other liabilities	(11,750,000)	17,585,000	35,079,000
Deferred revenue	1,798,000	7,184,000	5,849,000
Net cash provided by operating activities	116,221,000	112,899,000	98,617,000
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisition of property and equipment	(28,355,000)	(25,191,000)	(24,768,000)
Acquisition of internal-use software	(59,514,000)	(35,097,000)	(27,608,000)
Proceeds from sale of property and equipment	0	0	58,000
Purchases of investments	(221,383,000)	(62,533,000)	(60,816,000)
Maturities of investments	99,490,000	58,223,000	63,204,000
Sale of investments	0	20,000,000	0
Cash paid for acquisitions, net of cash acquired	(119,270,000)	0	(16,419,000)
Net cash used in investing activities	(329,032,000)	(44,598,000)	(66,349,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Payment of capital lease obligations	(619,000)	(3,827,000)	(3,745,000)
Proceeds from issuance of common stock under employee stock plans	19,306,000	17,297,000	14,199,000
Proceeds (payment of issuance costs) relating to common stock issued in public offering, net	(15,000)
Proceeds (payment of issuance costs) relating to common stock issued in public offering, net		271,379,000	0
Payments for repurchase of common stock	(35,244,000)	(663,000)	(31,530,000)
Tax payments related to shares withheld for vested restricted stock units	(13,826,000)	(5,976,000)	(3,552,000)
Net cash provided by (used in) financing activities	(30,398,000)	278,210,000	(24,628,000)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(243,209,000)	346,511,000	7,640,000
CASH AND CASH EQUIVALENTS, Beginning of period	380,907,000	34,396,000	26,756,000
CASH AND CASH EQUIVALENTS, End of period	137,698,000	380,907,000	34,396,000
Supplemental disclosure of cash flow information:
Cash paid for interest	515,000	294,000	133,000
Cash paid for (refunded from) income taxes	(1,299,000)	267,000	104,000
Supplemental disclosure of non-cash investing and financing activities:
Fixed asset purchases not yet paid	9,114,000	5,945,000	3,662,000
Stock-based compensation capitalized to property and equipment	$ 5,295,000	$ 2,831,000	1,126,000
Acquisition of property and equipment under capital leases			$ 6,998,000

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Ellie Mae, Inc. (“Ellie Mae” and the “Company”) is a leading cloud-based platform provider for the mortgage finance industry. The Company’s technology solutions enable lenders to originate and close residential mortgage loans. Banks, credit unions and mortgage lenders use the Company’s Encompass® all-in-one mortgage management solution (“Encompass”) to originate and fund mortgages and improve compliance, loan quality, and efficiency.

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated. Applicable Accounting Guidance Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative generally accepted accounting principles in the United States (“ U.S. GAAP ”), as found in the Financial Accounting Standards Board’s (“ FASB ”) Accounting Standards Codification (“ ASC ”). Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Management evaluates estimates on a regular basis including those relating to revenue recognition, allowance for doubtful accounts, goodwill, intangible assets, valuation of deferred income taxes, stock-based compensation, and unrecognized tax benefits, among others. Actual results could differ from those estimates and such differences may have a material impact on the Company’s consolidated financial statements and footnotes. Segment Information The Company operates in one industry—mortgage-related software and services. The Company’s chief operating decision maker is its chief executive officer, who makes decisions about resource allocation and reviews financial information presented on a consolidated basis. Accordingly, the Company has determined that it has a single reporting segment and operating unit structure, specifically technology-enabled solutions to help streamline and automate the residential mortgage origination process in the United States. Cash and Cash Equivalents All highly liquid investments with original maturities of 90 days or less are considered to be cash equivalents. Cash equivalents are recorded at cost, which approximates fair value. Fair Value Measurement of Financial Instruments The Company invests excess cash primarily in investment-grade, fixed maturity interest-bearing securities, such as money market accounts, certificates of deposit, commercial paper, corporate bonds, municipal and government agency obligations, and guaranteed obligations of the U.S. government. All of the Company’s investments that have maturities of greater than 90 days are classified as available-for-sale and are carried at fair value. For the Company’s remaining financial instruments, fair value is determined based on quoted market rates when observable or utilizing data points that are observable, such as quoted prices, interest rates, and yield curves. The cost of available-for-sale investments sold is based on the specific identification method. Unrealized gains and losses are reported in stockholders’ equity as accumulated other comprehensive income (loss) . Realized gains and losses are included in other income (expense), net . Interest and dividends are included in other income (expense), net when they are earned . Fair value is defined as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value measurements are classified and disclosed in one of the following three categories: Level 1 — Valuations based on quoted prices in active markets for identical assets or liabilities. Level 2 — Valuations based on other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 — Valuations based on inputs that are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the assets or liabilities. The fair values of the Company’s cash equivalents, accounts receivable, and accounts payable approximate their carrying values due to the short maturities of the instruments. The fair value of the Company’s capital lease obligations approximates the carrying value due to the terms continuing to approximate prevailing market terms. The Company classifies its money market funds that are specifically backed by debt securities and U.S. government obligations as Level 1 instruments, due to the use of observable market prices for identical securities that are traded in active markets. When the Company uses observable market prices for identical securities that are traded in less active markets, the Company classifies its marketable financial instruments as Level 2. When observable market prices for identical securities are not available, the Company prices its marketable financial instruments using non-binding market consensus prices that are corroborated with observable market data; quoted market prices for similar instruments; or pricing models with all significant inputs derived from or corroborated with observable market data. Non-binding market consensus prices are based on the proprietary valuation models of pricing providers. These valuation models incorporate a number of inputs, including non-binding and binding broker quotes; observable market prices for identical or similar securities; and the internal assumptions of pricing providers or brokers that use observable market inputs and, to a lesser degree, unobservable market inputs. The Company corroborates non-binding market consensus prices with observable market data as such data exists. Accounts Receivable and Allowance for Doubtful Accounts Trade accounts receivable consist of amounts billed to customers in connection with sale of services. The Company analyzes individual trade accounts receivable by considering historical bad debts, customer creditworthiness, current economic trends, changes in customer payment terms, and collection trends when evaluating the adequacy of the allowance for doubtful accounts. Allowances for doubtful accounts are recognized in the period in which the associated receivable balance is not considered recoverable. Any change in the assumptions used in analyzing accounts receivable may result in changes to the allowance for doubtful accounts and is recognized in the period in which the change occurs. The Company writes off a receivable when all rights, remedies, and recourse against the account and its principals are exhausted and records a benefit when previously reserved accounts are collected. Concentration of Credit Risk The financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents, investments, and accounts receivable. The Company’s cash and cash equivalents are deposited with major financial institutions in the United States. At times, such deposits may be in excess of federally insured limits. Management believes that the Company’s investments in cash equivalents and available-for-sale investments are financially sound. The Company’s accounts receivable are derived from revenue earned from customers located in the United States. The Company had no customers that represented 10% or more of revenues for the years ended December 31, 2017, 2016 and 2015 . No customer represented more than 10% of accounts receivable as of December 31, 2017 and 2016 . Property and Equipment Property and equipment are stated at cost less accumulated depreciation and are depreciated on a straight-line basis over their estimated useful lives, which is generally three to seven years. Leasehold improvements are amortized on a straight-line basis over their estimated useful lives or over the term of the lease, whichever is shorter. Software and Website Development Costs The Company capitalizes internal and external costs incurred to develop internal-use software and website applications. Capitalized internal costs include salaries, benefits, and stock-based compensation charges for employees that are directly involved in developing the software or website application, and depreciation of assets used in the development process. Capitalized external costs include third-party consultants involved in the development process, as well as other direct costs incurred therein. Capitalization of costs begins when the preliminary project stage has been completed, management authorizes and commits to funding a project and it is probable that the project will be completed and the software or website application will be used to perform the function intended. Internal and external costs incurred as part of the preliminary project stage are expensed as incurred. Capitalization ceases at the point at which the project is substantially complete and ready for its intended use. Internal and external training costs and maintenance costs during the post-implementation operation stage are expensed as incurred. Internal-developed core software is amortized on a straight-line basis over its estimated useful life, generally three to five years. Amortization of product related internal-use software and website applications is typically recorded to cost of revenues, and amortization of other internal-use software and website applications is typically recorded to the operating expense line to which it most closely relates. Management evaluates the useful lives of these assets on an annual basis and tests for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets. The capitalized costs are included in property and equipment, net in the accompanying consolidated balance sheets. For the years ended December 31, 2017 , 2016 and 2015 , the Company capitalized software and website application development costs of $64.6 million , $38.5 million and $29.4 million , respectively. Business Combinations The Company recognizes and measures the identifiable assets acquired in a business combination, the liabilities assumed and any non-controlling interest in the acquiree, at their fair values as of the acquisition date. The Company recognizes contingent consideration arrangements at their acquisition-date fair values with subsequent changes in fair value reflected in earnings, recognizes pre-acquisition loss and gain contingencies at their acquisition-date fair values, capitalizes in-process research and development assets and expenses acquisition-related transaction costs as incurred. Due to the inherent uncertainty in the estimates and assumptions used by the Company in its fair value measurements, recorded amounts may be subject to refinement. During the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the fair value of assets acquired and liabilities assumed, with the corresponding offset to goodwill. Any subsequent adjustments, including changes in accounting for deferred tax asset valuation allowances and acquired income tax uncertainties after the measurement period, are recognized in current period earnings. Goodwill The Company records goodwill in a business combination when the consideration paid exceeds the fair value of the identifiable net assets acquired. Goodwill is not amortized but is tested for impairment at least annually, or whenever changes in circumstances indicate that the fair value of a reporting unit is less than its carrying amount, including goodwill. The annual test is performed at the reporting unit level using a fair-value based approach. The Company’s operations are organized as one reporting unit. In testing for a potential impairment of goodwill, the Company first compares the net aggregate carrying value of assets and liabilities to the aggregate estimated fair value of the Company. If estimated fair value is less than carrying value, then potential impairment exists. On January 1, 2017, the Company early adopted Accounting Standards Update (“ ASU ”) No. 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment (“ASU 2017-04”). The standard eliminated Step 2 from the goodwill impairment test, which requires a hypothetical purchase price allocation. Impairment is equivalent to any excess of goodwill carrying value over its implied fair value. There were no impairment charges related to goodwill during the years ended December 31, 2017 , 2016 and 2015 . The process of evaluating the potential impairment of goodwill requires significant judgment at many points during the analysis, including calculating fair value of the reporting unit based on estimated future cash flows and discount rates to be applied. Intangible Assets Intangible assets are stated at cost less accumulated amortization. Intangible assets include developed technology, trade names, customer relationships, and order backlog. Intangible assets with finite lives are amortized on a straight-line basis over the estimated periods of benefit, as follows: Developed technology 2-8 years Trade names with finite lives 2-3 years Customer relationships 4-10 years Order backlog 1 year The AllRegs tradename is the only intangible asset with an indefinite useful life. The Company evaluates the remaining useful life of indefinite-lived intangible assets each reporting period to determine whether events and circumstances continue to support an indefinite useful life. The Company tests intangible assets with indefinite lives at least annually or if events or circumstances indicate that such assets might be impaired. If potential impairment exists, the amount of any impairment is calculated by using a discounted cash flow model, which is based on the assumptions the Company believe hypothetical marketplace participants would use. For indefinite-lived intangible assets, other than goodwill, if the carrying amount exceeds the fair value, an impairment charge is recognized in an amount equal to that excess. The Company evaluates its finite-lived intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset or asset group to future undiscounted net cash flows expected to be generated by the asset or asset group. If such assets or asset groups are considered to be impaired, the impairment loss to be recognized is measured by the amount by which the carrying amounts of the assets or asset groups exceed the fair value of the assets or asset groups. Assets to be disposed of are reported at the lower of the carrying amount and fair value less costs to sell. Impairment of Long-Lived Assets The Company evaluates its long-lived assets for indications of possible impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. There has been no loss on impairment or disposal of long-lived assets. Revenue Recognition The Company generates revenue primarily from transaction-based fees and fees for software and related services, including its annual user conference and fees from professional services. Our revenues are generated from the company-hosted Encompass Software subscriptions that customers access through the Internet. Revenues are also comprised of fees for software services sold both as a subscription and transactionally, including fees based on a per closed loan, or success basis, subject to monthly base fees, which the Company refers to as Success-Based Pricing; Ellie Mae Network fees; education and training, loan product, policy and guideline data and analytics services under the AllRegs brand ; and professional services which include consulting, implementation, and training services. Sales taxes assessed by governmental authorities are excluded from revenue. The Company commences revenue recognition when all of the following conditions are satisfied: • There is persuasive evidence of an arrangement; • The service has been or is being provided to the customer; • The collection of the fees is reasonably assured; and • The amount of fees to be paid by the customer is fixed or determinable. The Company also generates revenues from sales of services including subscription services and usage-based fees, transactional services, and professional services. Subscription Services and Usage-Based Fee Arrangements. Subscription services and usage-based fee arrangements generally include a combination of the Company’s products delivered as software-as-a-service (“SaaS”) and support services. These arrangements are generally non-cancelable and do not contain refund-type provisions. These revenues typically include the following: Encompass Revenues. The Company offers web-based, on-demand access to Encompass software for a monthly recurring fee. The Company provides the right to access its loan origination software and handles the responsibility of managing the servers, providing security, backing up the data and applying updates. Customers under SaaS arrangements do not take possession of the software at any time during the term of the agreement. Subscription revenues are recognized ratably over the contract terms as subscription services are provided, beginning on the commencement date of each contract, which is the date the Company’s service is made available to customers. Contracts generally range from one year to five years . Alternatively, customers can elect to pay on a success basis. Success basis contracts generally have a term of one to five years and are subject to monthly base fees, which enable customers to close loans up to a contractually agreed-to minimum number of transactions, and additional closed loan fees, which are assessed for loans closed in excess of the minimum. Revenues are earned from both base fees and additional closed loan fees as the result of the customer’s usage of Encompass. Monthly base fees are recognized over the respective monthly service period as the subscription services are provided. Additional closed loans fees are recognized when the loans are reported as closed. This offering also includes Encompass Consumer Connect, Encompass Compliance Service, and Encompass Docs Solution as integrated components, which are combined elements of the arrangement that are delivered in conjunction with the Encompass offering and therefore are not accounted for separately. Services Revenues. The Company provides a variety of mortgage-related and other business services, including: automated documentation; fraud detection, valuation, validation, and risk analysis; income verification; marketing and customer relationship management; product and pricing; flood zone certifications; website and electronic document management; and compliance reports. Services revenues are recognized upon completion of the services. Transactional and Other Revenues. The Company has entered into agreements with various lenders, service providers and certain government-sponsored entities participating in the mortgage origination process that provide them access to, and ability to interoperate with, mortgage originators on the Ellie Mae Network. Under these agreements, the Company earns transaction fees when transactions are processed through the Ellie Mae Network. Transactional and other revenues are recognized upon completion of the services. Professional Services Revenues. Professional services revenues are generally recognized upon delivery or completion for fixed price contracts or as the services are rendered for time and material contracts. The majority of the Company’s professional services contracts are on a fixed price basis. Training revenues are recognized as the services are rendered. Subscriptions to Online Research and Data Resources. The Company provides mortgage originators and underwriters with access to online databases of various federal and state laws and regulations and forms as well as investor product guidelines. Subscription fees are recognized ratably over the subscription term as subscription services are provided, which is typically one year. Multiple Element Arrangements The Company enters into arrangements with multiple elements that generally include multiple subscriptions and professional services. For arrangements with multiple deliverables , the Company evaluates whether the individual deliverables qualify as separate units of accounting. In order to treat deliverables in a multiple-deliverable arrangement as separate units of accounting, the deliverables must have standalone value upon delivery. Subscription services have standalone value as such services are often sold separately. Additionally, the Company concluded that professional services included in multiple element arrangements also have standalone value. In establishing standalone value, the Company considered the following factors for each professional services agreement: availability of the services from other vendors, the nature of the professional services, and the timing of when the professional services contract was signed in comparison to the subscription service start date. When subscription services agreements involve multiple elements that qualify as separate units of accounting, the Company allocates arrangement consideration to all deliverables at the inception of an arrangement based on the relative selling price method in accordance with the selling price hierarchy, which includes: (i) vendor specific objective evidence (“VSOE”) if it is available; (ii) third-party evidence (“TPE”) if VSOE is not available; and (iii) the best estimate of selling price (“BESP”) if neither VSOE nor TPE is available. The Company has determined that TPE is not a practical alternative as the Company’s go-to-market strategy and offerings contain a significant level of differentiation such that the comparable pricing of services with similar functionality cannot be obtained. Furthermore, the Company is unable to reliably determine what similar competitor services’ selling prices are on a standalone basis. The amount of revenue allocated to delivered items is limited by contingent revenue, if any. The Company has not historically priced its services within a narrow range. As a result, the Company has not been able to establish VSOE for its services. Accordingly, the Company uses its BESP to determine the relative selling price for its services. The objective of BESP is to determine the price at which the Company would transact a sale if the service was sold on a standalone basis. When establishing BESP, the Company reviews company-specific factors used to determine list price and makes adjustments as appropriate to reflect current market conditions and pricing behavior. The Company’s process for establishing list price includes assessing the cost to provide a particular product or service, surveying customers to determine market expectations, analyzing customer demographics, and taking into account similar products and services historically sold by the Company. The Company continues to review the factors used to establish list price and adjusts BESP as necessary. Deferred Revenues Deferred revenues represent billings or payments received in advance of revenue recognition and is recognized as the revenue recognition criteria are met. Balances consist primarily of prepaid subscription services and professional and training services not yet provided as of the balance sheet date. Deferred revenues that will be recognized during the succeeding 12 month period are recorded as current deferred revenues, and the remaining portion is recorded as other long-term liabilities. Long-term deferred revenue at December 31, 2017 and 2016 was not material. Deferred Commission Expenses Deferred commission expenses are the incremental costs that are directly associated with non-cancelable subscription contracts with customers and consist of sales commissions paid to the Company’s direct sales force. Commissions are calculated based on a percentage of the revenues for the non-cancelable term of subscription contracts, which are typically one to five years . The deferred commission expense amounts are recoverable through the future revenue streams under the non-cancelable customer contracts. During the years ended December 31, 2017 , 2016 , and 2015 , the Company deferred $4.3 million , $4.9 million , and $3.6 million of commission expenses, respectively. At December 31, 2017 and 2016 , $8.5 million and $7.8 million of deferred commission remained on the Company’s consolidated balance sheets, respectively. Warranties and Indemnification The Company provides a warranty for its software products and services to its customers and accounts for its warranties as a contingent liability. The Company’s software is generally warranted to perform substantially as described in the associated product documentation and to satisfy defined levels of uptime reliability. The Company’s services are generally warranted to be performed consistent with industry standards. The Company has not provided for a warranty accrual as of December 31, 2017 or 2016 . To date, the Company’s product warranty expense has not been significant. The Company generally agrees to indemnify its customers against legal claims that the Company’s software products infringe certain third-party intellectual property rights and accounts for its indemnification obligations as a contingent liability. In addition, the Company may also incur liability under its contracts if it breaches its warranties as well as certain data security and/or confidentiality obligations. To date, the Company has not been required to make any payment resulting from either infringement claims asserted against its customers or from claims in connection with a breach of the data security and/or confidentiality obligations in the Company’s contracts. The Company has not recorded a liability for related costs as of December 31, 2017 or 2016 . The Company has obligations under certain circumstances to indemnify each executive officer and member of the Company’s board of directors against judgments, fines, settlements, and expenses related to claims against such executive officer or director and otherwise to the fullest extent permitted under Delaware law and the Company’s bylaws and certificate of incorporation. Cost of Revenues The Company’s cost of revenues consists primarily of: salaries and benefits, including stock-based compensation expense; data center operating costs; depreciation on data center computer equipment; amortization of internal-use software and acquired intangible assets such as developed technology and trade names; customer support; professional services associated with implementation of the Company’s software; third-party royalty expenses; and allocated facilities costs. Research and Development Costs The Company’s research and development expenses consist primarily of: salaries and benefits, including bonuses and stock-based compensation expense; fees to contractors engaged in the development and support of the Ellie Mae Network , Encompass software and other products; and allocated facilities costs. Research and development costs that are not capitalized as internal-use software are expensed as they are incurred. Advertising Expenses The Company expenses advertising costs as incurred. Advertising expenses for the years ended December 31, 2017, 2016 and 2015 were $1.3 million , $1.0 million , and $0.7 million , respectively. Stock-Based Compensation The Company recognizes stock-based compensation related to awards granted under its 2009 Stock Option and Incentive Plan (the “ 2009 Plan ”), 2011 Equity Incentive Award Plan (the “ 2011 Plan ”), and Employee Stock Purchase Plan (“ ESPP ”). The Company recognizes compensation expense related to Restricted Stock Units (“ RSUs ”), Performance-Vesting Restricted Stock Units and Performance Awards (“ Performance Awards ”) based on the fair market value of the underlying shares of common stock as of the date of grant. Expense related to the RSUs is recognized on a straight-line basis over the requisite service period of the award, which generally equals the vesting period. Expense related to the Performance Awards and performance-vesting RSUs is recognized under the graded vesting method over the requisite service period of the award, which results in the recognition of a larger portion of the expense during the beginning of the vesting period than in the end of the vesting period. Management evaluates the probability of performance attainment and estimates the probable number of shares of common stock that will be granted and records the expense accordingly, if probable. The Company recognizes compensation expense related to stock option grants that are ultimately expected to vest based on estimated fair values on the date of grant using the Black-Scholes option-pricing model. Such expense is recognized on a straight-line basis over the requisite service period of the award, which generally equals the vesting period. The date of grant is the date at which the Company and the employee reach a mutual understanding of the key terms and conditions of the award, appropriate approvals are received by the equity incentive committee of the board of directors and the Company becomes contingently obligated to issue equity instruments to the employee who renders the requisite service . The Company estimates potential forfeitures of stock grants and adjust recorded compensation cost accordingly. The estimate of forfeitures is based on historical experience and is adjusted over the requisite service period to the extent that actual forfeitures differ, or are expected to differ, from the prior estimates. Changes in estimated forfeitures will be recognized in the period of change and will impact the amount of stock-based compensation expense to be recognized in future periods . Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of taxes payable or refundable for the current year, and deferred tax liabilities and assets for the future tax consequences of events that have been recognized in our financial statements or tax returns. The measurement of current and deferred tax liabilities and assets is based on provisions of the enacted tax law. The Company operates in various tax jurisdictions and is subject to audit by various tax authorities. The Company recognizes the tax benefit of an uncertain tax position only if it is more likely than not that the position is sustainable upon examination by the taxing authority, based on the technical merits. The tax benefit recognized is measured as the largest amount of benefit which is greater than 50 percent likely to be realized upon settlement with the taxing authority. The Company recognizes interest accrued and penalties related to unrecognized tax benefits in the income tax provision. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts that are more likely than not expected to be realized based on the weighting of positive and negative evidence. Future realization of deferred tax assets ultimately depends on estimates of future sources of taxable income for the jurisdictions in which the Company operates and the periods over which the deferred tax assets will be realizable. To the extent the Company establishes a valuation allowance or change the valuation allowance in a period, the Company reflects the change with a corresponding increase or decrease to the tax provision in the consolidated statements of operations. In relation to the Company’s adoption of ASU No. 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), on January 1, 2017, the Company records excess tax benefits and tax deficiencies as an income tax benefit or expense when stock awards vested or settled and, on a retrospective basis, the excess tax benefits are classified as an operating activity in the Company’s consolidated statements of cash flows. Comprehensive Income Comprehensive income consists of net income and other comprehensive income . Other comprehensive income includes certain changes in equity that are excluded from net income, specifically unrealized gains (losses) on marketable securities. Except for net realized gain (loss) on investments w

Net Income Per Share of Common

Net Income Per Share of Common Stock	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Net Income Per Share of Common Stock	Net Income Per Share of Common Stock Net income per share of common stock is calculated by dividing net income by the weighted average shares of common stock outstanding during the period. Diluted net income per share of common stock is calculated by dividing net income by the weighted average shares of common stock outstanding and potential shares of common stock during the period. Potential shares of common stock include dilutive shares attributable to the assumed exercise of stock options, RSUs , performance-vesting RSUs, Performance Awards , and ESPP shares using the treasury stock method, if dilutive. The components of net income per share of common stock were as follows: Year ended December 31, 2017 2016 2015 (in thousands, except share and per share amounts) Net income $ 52,850 $ 37,776 $ 22,258 Weighted average common shares outstanding used to compute basic net income per share 34,056,962 31,179,857 29,179,352 Effect of potentially dilutive securities: Employee stock options, RSUs, performance-vesting RSUs, Performance Awards and ESPP shares 1,748,562 1,619,928 1,663,232 Weighted average common shares outstanding used to compute diluted net income per share 35,805,524 32,799,785 30,842,584 Net income per share: Basic $ 1.55 $ 1.21 $ 0.76 Diluted $ 1.48 $ 1.15 $ 0.72 The following potential weighted average common shares were excluded from the computation of diluted net income per share, as their effect would have been anti-dilutive: Year ended December 31, 2017 2016 2015 Employee stock options and awards 212,257 48,374 225,122 Performance-vesting RSUs and Performance Awards are included in the diluted shares outstanding for each period if the established performance criteria have been met at the end of the respective periods. However, if none of the required performance criteria have been met for such awards, the Company includes the number of shares that would be issuable if the end of the reporting period were the end of the contingency period. Accordingly, in addition to the employee stock options and awards noted above, 15,954 and 20,304 shares underlying performance-vesting RSUs and Performance Awards were excluded from the dilutive shares outstanding for the years ended December 31, 2017 and 2016 , respectively. No shares were excluded from the dilutive shares outstanding for the year ended December 31, 2015 .

Financial Instruments and Fair

Financial Instruments and Fair Value Measurement	12 Months Ended
	Dec. 31, 2017
Financial Instruments and Fair Value Measurements [Abstract]
Financial Instruments and Fair Value Measurement	Financial Instruments and Fair Value Measurement As of December 31, 2017 and 2016 , the Company’s cash, cash equivalents and investments were primarily comprised of cash and investment-grade, fixed maturity interest-bearing debt securities, such as money market funds, certificates of deposit, commercial paper, corporate bonds, municipal and government agency obligations, and guaranteed obligations of the United States government. Cash equivalents and investments are recorded at fair value. All investments are considered available for sale. The following table summarizes cash and investments in financial instruments that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy by investment type: December 31, 2017 December 31, 2016 (1) Amortized Cost Unrealized Gains Unrealized Losses Carrying or Fair Value Amortized Unrealized Gains Unrealized Losses Carrying or (in thousands) (in thousands) Cash $ 119,035 $ — $ — $ 119,035 $ 76,538 $ — $ — $ 76,538 Level 1: Money market funds 3,623 — — 3,623 2,733 — — 2,733 U.S. government and government agency obligations 52,255 — (266 ) 51,989 156,240 2 (3 ) 156,239 174,913 — (266 ) 174,647 235,511 2 (3 ) 235,510 Level 2: Corporate notes and obligations 81,062 — (304 ) 80,758 28,978 1 (87 ) 28,892 Certificates of deposit 6,527 2 — 6,529 12,094 13 (19 ) 12,088 Municipal obligations 10,274 — (46 ) 10,228 11,422 1 (62 ) 11,361 U.S. government and government agency obligations 76,510 — (266 ) 76,244 180,893 14 (79 ) 180,828 Total financial instruments 349,286 2 (882 ) 348,406 468,898 31 (250 ) 468,679 Less investments 211,588 2 (882 ) 210,708 87,996 23 (247 ) 87,772 Cash and cash equivalents $ 137,698 $ — $ — $ 137,698 $ 380,902 $ 8 $ (3 ) $ 380,907 ________________ (1) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements. As of December 31, 2017 and 2016 , the Company did not have any assets or liabilities that were valued using Level 3 inputs. For the years ended December 31, 2017, 2016 and 2015 , there were no transfers of financial instruments between the levels. For the years ended December 31, 2017, 2016 and 2015 , the Company recognized interest income from financial instruments of $3.3 million , $1.1 million and $0.7 million , respectively. Gross realized gains and gross realized losses from the sale of investments were not significant during the years ended December 31, 2017, 2016 and 2015 . The following table shows the gross unrealized losses and the related fair values of the Company’s investments that have been in a continuous unrealized loss position. The Company did not identify any investments as other-than-temporarily impaired at December 31, 2017 or December 31, 2016 based on its evaluation of available evidence, such as whether it is the Company’s intent to hold an investment to its contractual maturity date and whether it is more likely than not that the Company will be required to sell the investment before recovery of the investment’s amortized basis. The Company typically expects to receive the full principal and interest on its investments. December 31, 2017 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands) Corporate notes and obligations $ 62,099 $ (253 ) $ 7,574 $ (51 ) $ 69,673 $ (304 ) Certificates of deposit 482 — 1,348 — 1,830 — U.S. government, government agency, and municipal obligations 119,456 (492 ) 13,070 (86 ) 132,526 (578 ) Total $ 182,037 $ (745 ) $ 21,992 $ (137 ) $ 204,029 $ (882 ) December 31, 2016 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands) Corporate notes and obligations $ 26,076 $ (87 ) $ — $ — $ 26,076 $ (87 ) Certificates of deposit 5,651 (19 ) — — 5,651 (19 ) U.S. government, government agency, and municipal obligations 180,138 (144 ) 385 — 180,523 (144 ) Total $ 211,865 $ (250 ) $ 385 $ — $ 212,250 $ (250 ) The following table summarizes the contractual maturities of the Company’s investments at December 31, 2017 : Amortized Cost Carrying or Fair Value (in thousands) Due within one year $ 103,508 $ 103,345 Due after one year through three years (1) 108,080 107,363 Total $ 211,588 $ 210,708 ________________ (1) Maximum maturity of individual investments is three years. Actual maturities may differ from the contractual maturities because borrowers may have the right to call or prepay certain obligations.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Acquisitions	Acquisitions Velocify, Inc. On October 2, 2017 , the Company acquired the outstanding stock of Velocify, Inc. (“Velocify”), a leading cloud-based sales engagement platform that provides customers the capabilities to generate and manage leads and customer relationships. The Company acquired the Velocify business in order to add functionality to its product offerings, including lead management, engagement and distribution capabilities. The transaction was accounted for as a business combination and, accordingly, the total purchase price was allocated to the assets acquired and liabilities assumed based on their respective fair values. The total purchase consideration was approximately $130.0 million in cash, of which $16.0 million was placed in escrow to cover closing capital settlement adjustments and any indemnity claims, and any amount remaining in escrow 18 months after the date of acquisition will be paid to the seller. The allocation of the purchase consideration to the identifiable tangible and intangible assets acquired and liabilities assumed under the purchase method of accounting, based on their estimated fair values as of the acquisition date, is summarized in the following table (in thousands): Cash and cash equivalents $ 10,686 Other assets 3,510 Property and equipment 843 Identifiable intangible assets 73,100 Current liabilities (5,280 ) Deferred tax liability (21,206 ) Deferred revenue (1,600 ) Goodwill 69,904 Total purchase consideration $ 129,957 The excess of purchase consideration over the fair value of net tangible and identifiable intangible assets acquired was recorded as goodwill. The fair values assigned to tangible assets acquired, liabilities assumed and identifiable intangible assets are based on management’s estimates and assumptions. The deferred tax liability was primarily a result of the difference in the book basis and tax basis related to the identifiable intangible assets. The preliminary estimated fair values of assets acquired and liabilities assumed, including current and noncurrent income taxes payable, deferred taxes, and certain identifiable intangible assets, may be subject to change as additional information is received and certain tax returns are finalized. Thus, the provisional measurements of fair value set forth above are subject to change. The Company expects to finalize the valuation as soon as practicable, but not later than one year from the acquisition date. The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the date of acquisition. Fair Value Useful Life (in thousands) (in years) Developed technology $ 42,000 8.0 Customer relationships 15,500 10.0 Order backlog 14,000 1.0 Trade name 1,600 3.0 Identifiable intangible assets $ 73,100 Developed technology consists of the technology underlying Velocify’s existing products and the Company expects to incorporate it into our Encompass product in the future. Customer relationships represents the fair values of the underlying relationships with Velocify’s customers. Order backlog represents estimated net discounted future cash flows associated with service contracts that were outstanding as of the acquisition date and expected to be completed within one year. Trade name represents the right to use the Velocify trade name over a useful life of three years. The goodwill balance is not deductible for tax purposes.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill The Company completed its annual goodwill impairment tests during the fourth quarter of 2017 , 2016 and 2015 and determined that goodwill was not impaired. The change in the carrying value of goodwill during the period ended December 31, 2017 was as follows (in thousands): Balance at December 31, 2015 $ 74,547 No changes — Balance at December 31, 2016 74,547 Addition: Velocify acquisition 69,904 Balance at December 31, 2017 $ 144,451 Intangible Assets Intangible assets, net, consisted of the following: December 31, 2017 Gross carrying Accumulated Net intangibles Weighted Average Remaining Useful Life (in thousands) (in years) Assets subject to amortization: Developed technology $ 53,535 $ (10,810 ) $ 42,725 7.5 Trade names 1,931 (464 ) 1,467 2.8 Customer relationships 34,900 (13,050 ) 21,850 7.7 Order backlog 14,370 (3,577 ) 10,793 0.8 Total assets subject to amortization 104,736 (27,901 ) 76,835 6.5 Assets not subject to amortization: Trade name 4,039 — 4,039 Total intangible assets $ 108,775 $ (27,901 ) $ 80,874 December 31, 2016 Gross carrying Accumulated Net intangibles Weighted Average Remaining Useful Life (in thousands) (in years) Assets subject to amortization: Developed technology $ 11,535 $ (8,183 ) $ 3,352 2.7 Trade names 331 (331 ) — 0.0 Customer relationships 19,400 (9,762 ) 9,638 4.0 Order backlog 370 (110 ) 260 2.8 Total assets subject to amortization 31,636 (18,386 ) 13,250 3.6 Assets not subject to amortization: Trade name 4,039 — 4,039 Total intangible assets $ 35,675 $ (18,386 ) $ 17,289 Amortization expense associated with intangible assets was $9.5 million , $5.5 million and $5.2 million for the years ended December 31, 2017, 2016 and 2015 , respectively. Minimum future amortization expense for intangible assets at December 31, 2017 was as follows (in thousands): 2018 $ 20,951 2019 10,549 2020 9,028 2021 7,164 2022 7,105 Thereafter 22,038 $ 76,835

Other Balance Sheet Components

Other Balance Sheet Components	12 Months Ended
	Dec. 31, 2017
Statement of Financial Position [Abstract]
Other Balance Sheet Components	Other Balance Sheet Components Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following: December 31, 2017 2016 (in thousands) Prepaid expenses $ 13,494 $ 11,568 Deferred commissions, current portion 3,533 2,761 Other current assets 1,447 880 $ 18,474 $ 15,209 Property and Equipment, net Property and equipment, net, consisted of the following: December 31, 2017 2016 (in thousands) Computer equipment and software $ 67,068 $ 54,029 Internal-use software (1) 108,710 62,573 Furniture and fixtures 8,311 6,838 Leasehold improvements 27,356 18,532 Internal-use software and other assets not yet placed in service 52,659 33,316 Property and equipment, gross 264,104 175,288 Accumulated depreciation and amortization (77,113 ) (48,991 ) Property and equipment, net $ 186,991 $ 126,297 ________________ (1) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements. At December 31, 2017 and 2016 , the Company had unamortized internal-use software costs of $124.4 million and $77.2 million , respectively. Amortization of internal-use software for the years ended December 31, 2017 , 2016 , and 2015 was $17.7 million , $8.3 million , and $2.4 million , respectively. Depreciation expense for the years ended December 31, 2017, 2016 and 2015 was $36.5 million , $20.5 million , and $10.8 million , respectively. These amounts include amortization of assets under capital leases of $2.8 million , $3.2 million , and $2.5 million for the years ended December 31, 2017 , 2016 , and 2015 , respectively. Accrued and Other Current Liabilities Accrued and other current liabilities consisted of the following: December 31, 2017 2016 (in thousands) Accrued payroll and related expenses $ 18,018 $ 31,848 Accrued commissions 1,480 1,832 Accrued royalties 1,630 1,395 Sales and other taxes 1,737 2,327 Other accrued expenses (1) 3,323 2,407 $ 26,188 $ 39,809 ________________ (1) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements. Deferred Revenue Deferred revenues consisted of the following: December 31, 2017 2016 (in thousands) Professional services and training $ 11,350 $ 10,729 Subscriptions 10,565 8,419 Other 4,772 4,140 Total 26,687 23,288 Less portion included in other long-term liabilities (400 ) (162 ) $ 26,287 $ 23,126 Other Long-Term Liabilities Other long-term liabilities consisted of the following: December 31, 2017 2016 (in thousands) Deferred revenue $ 400 $ 162 Deferred rent 13,443 9,512 Deferred tax liability 4,963 5,564 Other long-term liabilities (1) 74 2,494 $ 18,880 $ 17,732 ________________ (1) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The components of the provision for income taxes were as follows: Year ended December 31, 2017 2016 2015 (in thousands) Current Federal $ 156 $ 9,428 $ 8,070 State 305 1,664 1,894 461 11,092 9,964 Deferred Federal (11,793 ) 7,124 1,899 State 3,876 614 356 (7,917 ) 7,738 2,255 Income tax provision (benefit) $ (7,456 ) $ 18,830 $ 12,219 The provision for income taxes differed from the amount of income taxes determined by applying the U.S. statutory federal income tax rate as follows: Year ended December 31, 2017 2016 2015 Tax at federal statutory rate 35 % 35 % 35 % State taxes, net of federal benefit 7 4 5 Excess tax benefits related to stock-based compensation (1) (35 ) 1 1 Research and development tax credits (12 ) (6 ) (7 ) Re-measurement of net deferred tax liabilities arising from The Tax Act (19 ) — — Other non-deductible items (2) 4 — 1 Other 4 (1 ) — Income tax provision (benefit) (16 )% 33 % 35 % ________________ (1) In 2017, due to the adoption of ASU 2016-09, the excess tax benefits resulted from the vesting or the settlement of the stock awards were recorded in the tax provision. (2) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements. The components of net deferred tax assets (liabilities) were as follows: December 31, 2017 2016 (in thousands) Deferred tax assets Research and development credits $ 29,461 $ 5,089 Stock-based compensation 8,765 12,551 Reserves and accruals 5,894 11,896 Net operating loss carryforwards 16,422 — Total deferred tax assets 60,542 29,536 Valuation allowance (11,908 ) (5,089 ) Total deferred tax assets, net of valuation allowance 48,634 24,447 Deferred tax liabilities Depreciation and amortization (50,360 ) (28,749 ) Book/tax basis in acquired assets (1,360 ) (1,262 ) Total deferred tax liabilities (51,720 ) (30,011 ) Net deferred tax liabilities $ (3,086 ) $ (5,564 ) The Company continues to maintain a valuation allowance against the deferred tax assets related to certain state research and development tax credits, the realization of which is uncertain as the Company expects to generate additional credits at a faster rate than it is able to utilize them . The valuation allowance increased by $6.8 million , $1.2 million and $1.0 million in 2017 , 2016 and 2015 , respectively. As of December 31, 2017 , the Company had federal net operating loss (“ NOL ”) carryforwards of $68.7 million , available to reduce future taxable income and $38.6 million of state NOL carryforwards. These federal and state NOL carryforwards will begin to expire commencing 2021 and 2018, respectively. As of December 31, 2017 , the Company also had federal and state research and development tax credit carryforwards of $22.0 million and $20.3 million , respectively. The federal tax credit carryforwards begin to expire commencing in 2020 . The state tax credit carryforwards may be carried forward indefinitely. On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act (“The Tax Act”). The Tax Act makes broad and complex changes to the U.S. tax code. Changes impacting the Company include, but are not limited to, (1) reducing the U.S. federal corporate tax rate from 35 percent to 21 percent; (2) eliminating the corporate alternative minimum tax (“AMT”) and changing how existing AMT credits can be realized; (3) creating a new limitation on deductible interest expense; (4) changing rules related to uses and limitations of net operating loss carryforwards created in tax years beginning after December 31, 2017; (5) bonus depreciation that will allow for full expensing of qualified property; (6) the repeal of the domestic production activity deduction; and (7) limitations on the deductibility of certain executive compensation. The SEC staff issued Staff Accounting Bulletin No. 118 (“SAB 118”), which provides guidance on accounting for the tax effects of The Tax Act. SAB 118 provides a measurement period that should not extend beyond one year from The Tax Act enactment date for companies to complete the accounting under FASB Accounting Standards Board (“ASC”) 740, Income Taxes (“ASC 740”). In accordance with SAB 118, a company must reflect the income tax effects of those aspects of The Tax Act for which the accounting under ASC 740 is complete. To the extent that a company’s accounting for certain income tax effects of The Tax Act is incomplete but it is able to determine a reasonable estimate, it must record a provisional estimate in the financial statements. If a company cannot determine a provisional estimate to be included in the financial statements, it should continue to apply ASC 740 on the basis of the provisions of the tax laws that were in effect immediately before the enactment of The Tax Act. As of December 31, 2017, the Company has not completed its accounting for the income tax effects of certain elements of The Tax Act. However, in connection with the initial analysis, the Company recorded a provisional net tax benefit based on reasonable estimates for those tax effects. The provisional net tax benefit is subject to revisions as the Company completes the analysis of The Tax Act, collects and prepares necessary data, finalizes the Velocify purchase accounting, and interprets any additional guidance issued by the U.S. Treasury Department, Internal Revenue Service (“IRS”) and FASB. Adjustments may materially impact the provision for income taxes and effective tax rate in the period in which the adjustments are made. The accounting for the tax effects of The Tax Act will be completed during the measurement period. The accounting for the following elements of The Tax Act is incomplete. However, the Company is able to make reasonable estimates of certain effects and, therefore, recorded provisional adjustments as follows: • The Tax Act reduces the corporate tax rate to 21 percent, effective January 1, 2018. Consequently, the Company has recorded a decrease related to net deferred tax liabilities of $8.6 million , with a corresponding net adjustment to the deferred income tax benefit of $8.6 million for the year ended December 31, 2017. • The Tax Act creates a new limitation on the deductibility of certain executive compensation and removes the exceptions for performance-based compensation. However, The Tax Act grants a “transition rule” to compensation stemming from written binding contracts entered on or before November 2, 2017. The Company estimated the tax adjustment related to the “transition rule” is immaterial. Unrecognized Tax Benefits At December 31, 2017 , the Company had $10.0 million of cumulative unrecognized tax benefits. If the benefits were to be recognized, $5.5 million would affect the effective tax rate and $4.5 million would reverse the valuation allowance against the deferred tax assets. The Company does not expect a significant change to its unrecognized tax benefits over the next twelve months. A reconciliation of the beginning and ending balance of gross unrecognized tax benefits is as follows for the periods indicated: Year ended December 31, 2017 2016 2015 (in thousands) Beginning balance $ 4,634 $ 3,440 $ 2,408 Additions based on tax positions related to the current year 5,420 1,334 1,023 Additions (reductions) based on tax positions related to prior years including acquisitions (26 ) (140 ) 9 Ending balance $ 10,028 $ 4,634 $ 3,440 The Company files income tax returns in the U.S. federal jurisdiction and various state jurisdictions. The Company’s tax years for 2000 and forward are subject to examination by the U.S. tax authorities and for 2000 and forward are subject to examination by the California tax authorities due to the carryforward of unutilized net operating losses and research and development credits. The Company believes that it has provided adequate reserves for its income tax uncertainties in all open tax years, and that it does not have any tax positions that it is reasonably possible would materially increase or decrease the gross unrecognized tax benefits within the next twelve months. The Company has a policy to classify accrued interest and penalties associated with uncertain tax positions together with the related liability, and the expenses incurred related to such accruals are included in the provision for income taxes. The Company did not incur any interest expense or penalties associated with unrecognized tax benefits during the years ended December 31, 2017, 2016 and 2015 .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Leases As of December 31, 2017 , the Company leased nine facilities under operating lease arrangements. The lease expiration dates range from September 2019 to December 2025. Certain leases contain escalation clauses calling for increased rents. The Company recognizes rent expense on a straight-line basis over the lease period and has recorded deferred rent for the difference between rent payments and rent expense recognized. Rent expense was $7.9 million , $5.4 million , and $4.2 million for the years ended December 31, 2017, 2016 and 2015 , respectively. Future minimum lease payments under non-cancelable operating and capital leases at December 31, 2017 consisted of the following: Capital Leases Operating Leases (in thousands) 2018 $ 87 $ 11,718 2019 — 12,349 2020 — 12,025 2021 — 11,306 2022 — 11,484 Thereafter — 34,363 Total minimum lease payments 87 $ 93,245 Less amount representing interest (2 ) Present value of minimum lease payments 85 Less current portion (85 ) Long-term portion of lease obligations $ — Purchase Commitments Commitments for the purchase of services, licenses of third-party software, and construction commitments totaled $66.6 million at December 31, 2017 and are to be paid as follows: $39.7 million in 2018 , $25.1 million in 2019 and $1.8 million in 2020 . Legal Proceedings On December 1, 2017, a pension fund and stockholder purporting to act on the Company’s behalf filed a derivative lawsuit in the Superior Court of California for the County of Alameda, captioned United Association of Plumbers and Pipefitters, Journeymen, Local #38 Defined Benefit Pension Plan v. Jonathan H. Corr, et al . (Case No. RG17884445). The lawsuit purports to assert claims against certain of the Company’s officers and directors for insider trading under California law, breach of fiduciary duty, corporate waste, and unjust enrichment based on allegations that: (1) the Company overstated its financial prospects in public filings between February 10, 2017 and July 27, 2017; and (2) certain of the Company’s officers and directors sold shares during this same period. Plaintiff seeks unspecified monetary damages, attorneys’ fees and costs, as well as certain changes to the Company’s corporate governance and internal procedures. Our demurrer to plaintiff’s complaint was filed on February 15, 2018. At this time, the Company is unable to estimate a probable loss for this matter, if any, and accordingly has not accrued for any amount. In addition, from time to time, the Company is involved in litigation that it believes is of the type common to companies engaged in the Company’s line of business, including commercial and employment disputes. As of the date of this Annual Report on Form 10-K, the Company is not involved in any other pending legal proceedings whose outcome the Company expects to have a material adverse effect on its financial position, results of operations or cash flows. However, litigation is unpredictable and excessive verdicts, both in the form of monetary damages and injunctions, could occur. In the future, litigation could result in substantial costs and diversion of resources and the Company could incur judgments or enter into settlements of claims that could have a material adverse effect on its business.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Common Stock The amended and restated certificate of incorporation of the Company authorizes 140,000,000 shares of common stock, $0.0001 par value per share and 10,000,000 shares of undesignated preferred stock, $0.0001 par value per share. The following number of shares of common stock were reserved and available for future issuance at December 31, 2017 : Reserved Shares Options and awards granted and outstanding under stock incentive plans 2,909,953 Shares available for future grant under the stock incentive plans 5,140,367 Shares available under the employee stock purchase plan 1,614,689 Total 9,665,009 Stock Offering In August 2016 , the Company completed a public offering of common stock and sold a total of 3,162,500 shares of its common stock for total cash proceeds of approximately $271.4 million , net of underwriting discounts, and offering costs and expenses of approximately $13.2 million . Stock Repurchase Program In May 2014, the Company’s board of directors approved a repurchase program which the Company is authorized to repurchase up to $75.0 million of its common stock over a 36-month period. All shares are retired upon repurchase. This program ended in May 2017 and the Company did not repurchase any shares in 2017 under this program . In August 2017, the Company’s audit committee, under the authority delegated to it by the Company’s board of directors, approved a new stock repurchase program under which the Company is authorized to repurchase up to $250.0 million of its common stock. This authorization expires in August 2020. All shares are retired upon repurchase. The Company repurchased the following shares of common stock under its repurchase programs: Shares Repurchased Weighted Average Purchase Price per Share Total Amount (in thousands) Year Ended 2017 401,188 $ 87.85 $ 35,244 Year Ended 2016 8,333 $ 79.62 $ 663 Year Ended 2015 503,450 $ 62.63 $ 31,530

Share-based Compensation

Share-based Compensation	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation	Share-based Compensation The Company recognized stock-based compensation expense related to awards granted under the 2009 Plan, the 2011 Plan, and ESPP . 2009 Stock Option and Incentive Plan and 2011 Equity Incentive Award Plan Stock Options In March 2011, the Company adopted the 2011 Plan , which was approved by the Company’s stockholders on March 24, 2011. Under the 2011 Plan , 2,666,666 shares of the Company’s common stock were initially reserved. Any shares of common stock that were available for issuance under prior plans, including the 2009 Plan, were transferred to the 2011 Plan . As of December 31, 2017 , the Company had 987,657 shares of its common stock previously available for issuance under the 2009 Plan available for issuance under the 2011 Plan. The majority of stock options issued under the plan have a maximum contractual term of ten years, the options generally vest over a four-year period. The number of common shares reserved for issuance under the 2011 Plan increase automatically in January of each year by the least of (a) 1,666,666 shares, (b) five percent ( 5% ) of the shares of common stock outstanding on the last day of the immediately preceding fiscal year and (c) such smaller number of shares of common stock as determined by the Company’s board of directors; provided, however that no more than 23,333,333 shares of common stock may be issued upon the exercise of incentive stock options. The following table summarizes the Company’s stock option activity under the 2009 Plan and 2011 Plan: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (in years) (in thousands) Outstanding at December 31, 2014 3,050,301 $ 17.41 Granted 385,776 $ 55.30 Exercised (822,133 ) $ 12.28 Forfeited or expired (98,615 ) $ 30.12 Outstanding at December 31, 2015 2,515,329 $ 24.40 Granted 14,506 $ 59.78 Exercised (584,807 ) $ 18.08 Forfeited or expired (59,696 ) $ 37.94 Outstanding at December 31, 2016 1,885,332 $ 26.21 Granted 6,601 $ 94.66 Exercised (432,341 ) $ 23.61 Forfeited or expired (23,561 ) $ 40.94 Outstanding at December 31, 2017 1,436,031 $ 27.06 5.43 $ 89,554 Ending vested and expected to vest at December 31, 2017 1,431,645 $ 26.98 5.42 $ 89,393 Exercisable at December 31, 2017 1,250,119 $ 24.05 5.18 $ 81,700 The aggregate intrinsic value of the stock options outstanding at December 31, 2017 based on the Company’s closing stock price of $89.40 is presented above. Intrinsic value of an option is the difference between the fair value of the Company’s common stock at the time of exercise and the exercise price to be paid. Options outstanding that are expected to vest are net of estimated future forfeitures. For the majority of stock options outstanding, the options vest over a four -year period and have a maximum contractual term of ten years. Following is additional information pertaining to the Company’s stock option activity: Year ended December 31, 2017 2016 2015 (in thousands except for per option data) Weighted average fair value per option granted $ 45.44 $ 27.57 $ 26.13 Grant-date fair value of options vested $ 4,994 $ 8,577 $ 8,285 Intrinsic value of options exercised $ 31,621 $ 39,040 $ 38,971 Proceeds received from options exercised $ 10,208 $ 10,573 $ 10,094 As of December 31, 2017 , total unrecognized stock-based compensation expense related to unvested stock options, adjusted for estimated forfeitures, was $3.8 million and is expected to be recognized over a weighted average period of 1.10 years. Restricted Stock Units, Performance-Vesting Restricted Stock Units, and Performance Awards The fair value of the Company’s RSUs and Performance Awards is measured based upon the closing price of its underlying common stock as of the grant date and is recognized over the vesting term. Upon vesting, RSUs convert into an equivalent number of shares of common stock. Restricted shares vest in full after four years. The estimated fair value of restricted shares under the Company's stock plans is determined by the product of the number of shares granted and the grant date market price of the Company's common stock. The estimated fair value of restricted shares is expensed on a straight-line basis over the requisite service period. Performance Awards and performance-vesting RSUs are granted to certain executives under the 2011 Plan , which represent common stock potentially issuable in the future. Performance stock awards and units vest over a four -year period and the number of shares to be awarded is determined based on the achievement of specific performance goals. Based on the extent to which the targets are achieved at the end of the performance period, vested shares may range from 0 percent to 200 percent of the target award amount. The fair value of performance stock awards and units is determined by the grant date market price of the Company's common stock, and the compensation expense associated with nonvested performance stock awards and units is recognized over the requisite service period and is dependent on the Company's periodic assessment of the probability of the targets being achieved and its estimate of the number of shares that will ultimately be issued. During the fiscal years ended December 31, 2017, 2016 and 2015 , the Company recognized $5.8 million , $8.3 million , and $7.4 million of compensation expense, respectively, related to these performance stock awards and units. In October 2015, in connection with the acquisition of Mortgage Returns, LLC (“Mortgage Returns”), the Company agreed to grant up to 29,006 of performance-vesting RSUs for a total value of $2.0 million to the former Chief Executive Officer of Mortgage Returns. The performance-vesting RSUs granted represent the right to receive shares of the Company’s common stock upon achievement of certain performance criteria and a service requirement during the performance period of October 23, 2015 through October 23, 2019. The performance-vesting RSUs will vest annually based on the achievement of the performance criteria and the service requirement. In December 2016, a modification was made to a performance criteria of the award to align certain performance metrics to the Company’s targets. The modification resulted in an incremental value of approximately $0.2 million that will be recognized over the remaining requisite period; dependent on the Company’s periodic assessment of the probability of achievement. The following table summarizes the Company’s RSU, Performance Award and performance-vesting RSU activity: RSUs Performance Awards and performance-vesting RSUs Number of Shares Weighted Average Grant Date Fair Value Per Share Number of Shares Weighted Average Grant Date Fair Value Per Share Outstanding at December 31, 2014 585,858 $ 27.20 485,177 $ 25.61 Granted 401,158 $ 62.62 205,816 $ 47.18 Released (179,530 ) $ 25.97 (182,711 ) $ 24.69 Forfeited or expired (58,798 ) $ 39.40 — $ — Outstanding at December 31, 2015 748,688 $ 45.52 508,282 $ 34.68 Granted 598,390 $ 78.39 151,540 $ 61.69 Released (240,386 ) $ 42.48 (239,120 ) $ 29.34 Forfeited or expired (81,577 ) $ 57.50 (13,052 ) $ 68.19 Outstanding at December 31, 2016 1,025,115 $ 64.47 407,650 $ 46.77 Granted 651,936 $ 97.73 43,414 $ 94.66 Released (355,045 ) $ 57.37 (150,727 ) $ 40.73 Forfeited or expired (142,548 ) $ 82.25 (5,873 ) $ 84.86 Outstanding at December 31, 2017 1,179,458 $ 82.84 294,464 $ 56.17 Ending vested and expected to vest at December 31, 2017 1,034,136 294,463 RSUs , performance-vesting RSUs and Performance Awards that are expected to vest are presented net of estimated future forfeitures. RSUs released during the years ended December 31, 2017 and 2016 had an aggregate intrinsic value of $36.0 million and $20.1 million , respectively, and an aggregate grant-date fair value of $20.4 million and $10.2 million , respectively. Performance-vesting RSUs and Performance Awards released during the years ended December 31, 2017 and 2016 had an aggregate intrinsic value of $14.2 million and $21.8 million , respectively, and an aggregate grant-date fair value of $6.1 million and $7.0 million , respectively. The number of RSUs released includes shares that the Company withheld on behalf of employees to satisfy the minimum statutory tax withholding requirements. As of December 31, 2017 , total unrecognized compensation expense related to unvested RSUs , performance-vesting RSUs and Performance Awards was $72.1 million and is expected to be recognized over a weighted average period of 2.46 years. Executive Incentive Plan On March 14, 2016, the Compensation Committee adopted the Ellie Mae, Inc. Executive Incentive Plan (the “Executive Incentive Plan”). The Executive Incentive Plan was approved by the Company’s stockholders on May 25, 2016. The Executive Incentive Plan has a term of five years from the date of approval by the stockholders, expiring May 25, 2021, and may be terminated, amended or suspended by the Compensation Committee at any prior time, and may also be reinstated. The Company issued cash bonus and performance-based equity awards under the Executive Incentive Plan to the Company’s executive officers in 2017. Shares underlying equity awards from the Executive Incentive Plan are issued from the Company’s 2011 Plan. The equity awards have the following limitations: Stock Option Limitations. The maximum number of shares that may be granted as an incentive stock option under the Executive Incentive Plan is 70,000,000 . No participant will be eligible to receive a stock option covering more than 1,000,000 shares in any calendar year. Performance Units/Performance Share Limitations. No participant will be eligible to receive performance units or performance shares having a grant date value (assuming maximum payout) greater than $10,000,000 or covering more than 1,000,000 shares, whichever is greater, in any calendar year. Due to changes in the deductibility of executive compensation under The Tax Act, the Company is currently evaluating whether future cash bonus and performance-based equity awards will continue to be issued under the Executive Incentive Plan. Employee Stock Purchase Plan Under the ESPP , qualified employees are permitted to purchase the Company’s common stock at 85% of the fair market value of the common stock as of the commencement date of the offering period or as of the specified purchase date, whichever is lower. The ESPP is deemed compensatory and stock-based compensation is recognized in accordance with ASC 718 , Stock Compensation. The ESPP is designed to allow eligible employees to purchase shares of common stock, at semi-annual intervals, with their accumulated payroll deductions. The weighted-average grant-date fair value of awards issued pursuant to the ESPP during the years ended December 31, 2017 , 2016 , and 2015 were $23.01 , $24.11 , and $16.12 per share, respectively. For the years ended December 31, 2017 , 2016 and 2015 , employees purchased 121,010 , 101,816 , and 110,598 shares under the ESPP for a total of $9.1 million , $6.7 million , and $4.1 million , respectively. As of December 31, 2017 , unrecognized compensation cost related to the current ESPP period which ends on February 28, 2018 was approximately $0.5 million and is expected to be recognized over the next 2 months . Valuation Information The fair value of stock options and stock purchase rights granted under the 2009 Plan, the 2011 Plan and the ESPP were estimated at the date of grant using the Black-Scholes option valuation model with the following weighted average assumptions: Year ended December 31, 2017 2016 2015 Stock option plans: Risk-free interest rate 2.04 % 1.38 % 1.50-1.96 % Expected life of options (in years) 6.08 6.08 5.00-6.08 Expected dividend yield — % — % — % Volatility 48 % 47 % 48-49 % Employee Stock Purchase Plan: Risk-free interest rate 0.46-0.69 % 0.46-0.48 % 0.13-0.24 % Expected life of options (in years) 0.5 0.5 0.5 Expected dividend yield — % — % — % Volatility 33-37 % 33-49 % 35-44 % The Company uses the simplified method to estimate the expected term of options granted by taking the average of the vesting term and the contractual term of the option. The Company estimated its future stock price volatility considering its historical volatility calculations. The risk-free interest rate used was the Federal Reserve Bank’s constant maturities interest rate commensurate with the expected life of the options. The expected dividend yield was zero, as the Company does not anticipate paying a dividend within the relevant time frame. Stock-Based Compensation Expense Total stock-based compensation expense recognized by the Company consisted of: Year ended December 31, 2017 2016 2015 (in thousands) Stock-based compensation by category of expense: Cost of revenues $ 6,786 $ 4,835 $ 3,218 Sales and marketing 5,223 4,429 2,752 Research and development 8,281 7,296 5,431 General and administrative 14,177 14,911 12,840 $ 34,467 $ 31,471 $ 24,241 The Company capitalized $5.3 million , $2.8 million , and $1.1 million of stock compensation costs as software and website application development costs for the years ended December 31, 2017 , 2016 , and 2015 , respectively.

Employee Benefit Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2017
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Employee Benefit Plan	Employee Benefit Plan The Company offers a qualified 401(k) defined contribution plan to substantially all of the Company’s employees. Eligible employees may contribute up to the annual amount allowed pursuant to the Internal Revenue Code. In the years ended December 31, 2017, 2016 and 2015 , the Company matched 50% of each dollar of employee contribution, up to a maximum match of three percent of the employee’s compensation. The Company’s contributions to the 401(k) plan for the years ended December 31, 2017, 2016 and 2015 were $3.9 million , $2.8 million , and $2.0 million , respectively, which were recognized as expense in the consolidated statements of comprehensive income.

Quarterly Results of Operations

Quarterly Results of Operations Data (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results of Operations Data (Unaudited)	Quarterly Results of Operations Data (Unaudited) Three months ended Dec 31, Sep 30, Jun 30, Mar 31, Dec 31, Sep 30, Jun 30, Mar 31, (in thousands, except per share amounts) Revenues $ 112,886 $ 107,029 $ 104,125 $ 93,002 $ 96,181 $ 100,381 $ 90,098 $ 73,625 Gross profit $ 64,614 $ 67,426 $ 65,858 $ 58,234 $ 63,338 $ 68,163 $ 61,645 $ 46,994 Income before income taxes $ 3,417 $ 18,984 $ 17,987 $ 5,006 $ 14,766 $ 21,272 $ 16,846 $ 3,722 Net income $ 9,909 $ 14,519 $ 18,823 $ 9,599 $ 10,902 $ 13,780 $ 10,588 $ 2,506 Net income per share, basic $ 0.29 $ 0.42 $ 0.55 $ 0.28 $ 0.33 $ 0.43 $ 0.36 $ 0.09 Net income per share, diluted $ 0.28 $ 0.41 $ 0.52 $ 0.27 $ 0.31 $ 0.41 $ 0.34 $ 0.08

SCHEDULE II VALUATION AND QUALI

SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	SCHEDULE II VALUATION AND QUALIFYING ACCOUNT FOR THE YEARS ENDED DECEMBER 31, 2017 , 2016 and 2015 (in thousands) Balance at Beginning of Period Charged (Credited) to Income Deductions and Other (a) Balance at End of Period Allowance for Doubtful Accounts: Year ended December 31, 2017 $ 45 $ 374 $ (79 ) $ 340 Year ended December 31, 2016 $ 124 $ 121 $ (200 ) $ 45 Year ended December 31, 2015 $ 66 $ 62 $ (4 ) $ 124 (a) Accounts written off, net of recoveries.

Basis of Presentation and Sig21

Basis of Presentation and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Management evaluates estimates on a regular basis including those relating to revenue recognition, allowance for doubtful accounts, goodwill, intangible assets, valuation of deferred income taxes, stock-based compensation, and unrecognized tax benefits, among others. Actual results could differ from those estimates and such differences may have a material impact on the Company’s consolidated financial statements and footnotes.
Segment Information	Segment Information The Company operates in one industry—mortgage-related software and services. The Company’s chief operating decision maker is its chief executive officer, who makes decisions about resource allocation and reviews financial information presented on a consolidated basis. Accordingly, the Company has determined that it has a single reporting segment and operating unit structure, specifically technology-enabled solutions to help streamline and automate the residential mortgage origination process in the United States.
Cash and Cash Equivalents	Cash and Cash Equivalents All highly liquid investments with original maturities of 90 days or less are considered to be cash equivalents. Cash equivalents are recorded at cost, which approximates fair value.
Fair Value Measurement of Financial Instruments	Fair Value Measurement of Financial Instruments The Company invests excess cash primarily in investment-grade, fixed maturity interest-bearing securities, such as money market accounts, certificates of deposit, commercial paper, corporate bonds, municipal and government agency obligations, and guaranteed obligations of the U.S. government. All of the Company’s investments that have maturities of greater than 90 days are classified as available-for-sale and are carried at fair value. For the Company’s remaining financial instruments, fair value is determined based on quoted market rates when observable or utilizing data points that are observable, such as quoted prices, interest rates, and yield curves. The cost of available-for-sale investments sold is based on the specific identification method. Unrealized gains and losses are reported in stockholders’ equity as accumulated other comprehensive income (loss) . Realized gains and losses are included in other income (expense), net . Interest and dividends are included in other income (expense), net when they are earned . Fair value is defined as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value measurements are classified and disclosed in one of the following three categories: Level 1 — Valuations based on quoted prices in active markets for identical assets or liabilities. Level 2 — Valuations based on other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 — Valuations based on inputs that are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the assets or liabilities. The fair values of the Company’s cash equivalents, accounts receivable, and accounts payable approximate their carrying values due to the short maturities of the instruments. The fair value of the Company’s capital lease obligations approximates the carrying value due to the terms continuing to approximate prevailing market terms. The Company classifies its money market funds that are specifically backed by debt securities and U.S. government obligations as Level 1 instruments, due to the use of observable market prices for identical securities that are traded in active markets. When the Company uses observable market prices for identical securities that are traded in less active markets, the Company classifies its marketable financial instruments as Level 2. When observable market prices for identical securities are not available, the Company prices its marketable financial instruments using non-binding market consensus prices that are corroborated with observable market data; quoted market prices for similar instruments; or pricing models with all significant inputs derived from or corroborated with observable market data. Non-binding market consensus prices are based on the proprietary valuation models of pricing providers. These valuation models incorporate a number of inputs, including non-binding and binding broker quotes; observable market prices for identical or similar securities; and the internal assumptions of pricing providers or brokers that use observable market inputs and, to a lesser degree, unobservable market inputs. The Company corroborates non-binding market consensus prices with observable market data as such data exists.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts Trade accounts receivable consist of amounts billed to customers in connection with sale of services. The Company analyzes individual trade accounts receivable by considering historical bad debts, customer creditworthiness, current economic trends, changes in customer payment terms, and collection trends when evaluating the adequacy of the allowance for doubtful accounts. Allowances for doubtful accounts are recognized in the period in which the associated receivable balance is not considered recoverable. Any change in the assumptions used in analyzing accounts receivable may result in changes to the allowance for doubtful accounts and is recognized in the period in which the change occurs. The Company writes off a receivable when all rights, remedies, and recourse against the account and its principals are exhausted and records a benefit when previously reserved accounts are collected.
Concentration of Credit Risk	Concentration of Credit Risk The financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents, investments, and accounts receivable. The Company’s cash and cash equivalents are deposited with major financial institutions in the United States. At times, such deposits may be in excess of federally insured limits. Management believes that the Company’s investments in cash equivalents and available-for-sale investments are financially sound. The Company’s accounts receivable are derived from revenue earned from customers located in the United States. The Company had no customers that represented 10% or more of revenues for the years ended December 31, 2017, 2016 and 2015 . No customer represented more than 10% of accounts receivable as of December 31, 2017 and 2016 .
Property and Equipment	Property and Equipment Property and equipment are stated at cost less accumulated depreciation and are depreciated on a straight-line basis over their estimated useful lives, which is generally three to seven years. Leasehold improvements are amortized on a straight-line basis over their estimated useful lives or over the term of the lease, whichever is shorter.
Software and Website Development Costs	Software and Website Development Costs The Company capitalizes internal and external costs incurred to develop internal-use software and website applications. Capitalized internal costs include salaries, benefits, and stock-based compensation charges for employees that are directly involved in developing the software or website application, and depreciation of assets used in the development process. Capitalized external costs include third-party consultants involved in the development process, as well as other direct costs incurred therein. Capitalization of costs begins when the preliminary project stage has been completed, management authorizes and commits to funding a project and it is probable that the project will be completed and the software or website application will be used to perform the function intended. Internal and external costs incurred as part of the preliminary project stage are expensed as incurred. Capitalization ceases at the point at which the project is substantially complete and ready for its intended use. Internal and external training costs and maintenance costs during the post-implementation operation stage are expensed as incurred. Internal-developed core software is amortized on a straight-line basis over its estimated useful life, generally three to five years. Amortization of product related internal-use software and website applications is typically recorded to cost of revenues, and amortization of other internal-use software and website applications is typically recorded to the operating expense line to which it most closely relates. Management evaluates the useful lives of these assets on an annual basis and tests for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets. The capitalized costs are included in property and equipment, net in the accompanying consolidated balance sheets. For the years ended December 31, 2017 , 2016 and 2015 , the Company capitalized software and website application development costs of $64.6 million , $38.5 million and $29.4 million , respectively.
Business Combinations	Business Combinations The Company recognizes and measures the identifiable assets acquired in a business combination, the liabilities assumed and any non-controlling interest in the acquiree, at their fair values as of the acquisition date. The Company recognizes contingent consideration arrangements at their acquisition-date fair values with subsequent changes in fair value reflected in earnings, recognizes pre-acquisition loss and gain contingencies at their acquisition-date fair values, capitalizes in-process research and development assets and expenses acquisition-related transaction costs as incurred. Due to the inherent uncertainty in the estimates and assumptions used by the Company in its fair value measurements, recorded amounts may be subject to refinement. During the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the fair value of assets acquired and liabilities assumed, with the corresponding offset to goodwill. Any subsequent adjustments, including changes in accounting for deferred tax asset valuation allowances and acquired income tax uncertainties after the measurement period, are recognized in current period earnings.
Goodwill	Goodwill The Company records goodwill in a business combination when the consideration paid exceeds the fair value of the identifiable net assets acquired. Goodwill is not amortized but is tested for impairment at least annually, or whenever changes in circumstances indicate that the fair value of a reporting unit is less than its carrying amount, including goodwill. The annual test is performed at the reporting unit level using a fair-value based approach. The Company’s operations are organized as one reporting unit. In testing for a potential impairment of goodwill, the Company first compares the net aggregate carrying value of assets and liabilities to the aggregate estimated fair value of the Company. If estimated fair value is less than carrying value, then potential impairment exists. On January 1, 2017, the Company early adopted Accounting Standards Update (“ ASU ”) No. 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment (“ASU 2017-04”). The standard eliminated Step 2 from the goodwill impairment test, which requires a hypothetical purchase price allocation. Impairment is equivalent to any excess of goodwill carrying value over its implied fair value. There were no impairment charges related to goodwill during the years ended December 31, 2017 , 2016 and 2015 . The process of evaluating the potential impairment of goodwill requires significant judgment at many points during the analysis, including calculating fair value of the reporting unit based on estimated future cash flows and discount rates to be applied.
Intangible Assets	Intangible Assets Intangible assets are stated at cost less accumulated amortization. Intangible assets include developed technology, trade names, customer relationships, and order backlog. Intangible assets with finite lives are amortized on a straight-line basis over the estimated periods of benefit, as follows: Developed technology 2-8 years Trade names with finite lives 2-3 years Customer relationships 4-10 years Order backlog 1 year The AllRegs tradename is the only intangible asset with an indefinite useful life. The Company evaluates the remaining useful life of indefinite-lived intangible assets each reporting period to determine whether events and circumstances continue to support an indefinite useful life. The Company tests intangible assets with indefinite lives at least annually or if events or circumstances indicate that such assets might be impaired. If potential impairment exists, the amount of any impairment is calculated by using a discounted cash flow model, which is based on the assumptions the Company believe hypothetical marketplace participants would use. For indefinite-lived intangible assets, other than goodwill, if the carrying amount exceeds the fair value, an impairment charge is recognized in an amount equal to that excess. The Company evaluates its finite-lived intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset or asset group to future undiscounted net cash flows expected to be generated by the asset or asset group. If such assets or asset groups are considered to be impaired, the impairment loss to be recognized is measured by the amount by which the carrying amounts of the assets or asset groups exceed the fair value of the assets or asset groups. Assets to be disposed of are reported at the lower of the carrying amount and fair value less costs to sell.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates its long-lived assets for indications of possible impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. There has been no loss on impairment or disposal of long-lived assets.
Revenue Recognition	Revenue Recognition The Company generates revenue primarily from transaction-based fees and fees for software and related services, including its annual user conference and fees from professional services. Our revenues are generated from the company-hosted Encompass Software subscriptions that customers access through the Internet. Revenues are also comprised of fees for software services sold both as a subscription and transactionally, including fees based on a per closed loan, or success basis, subject to monthly base fees, which the Company refers to as Success-Based Pricing; Ellie Mae Network fees; education and training, loan product, policy and guideline data and analytics services under the AllRegs brand ; and professional services which include consulting, implementation, and training services. Sales taxes assessed by governmental authorities are excluded from revenue. The Company commences revenue recognition when all of the following conditions are satisfied: • There is persuasive evidence of an arrangement; • The service has been or is being provided to the customer; • The collection of the fees is reasonably assured; and • The amount of fees to be paid by the customer is fixed or determinable. The Company also generates revenues from sales of services including subscription services and usage-based fees, transactional services, and professional services. Subscription Services and Usage-Based Fee Arrangements. Subscription services and usage-based fee arrangements generally include a combination of the Company’s products delivered as software-as-a-service (“SaaS”) and support services. These arrangements are generally non-cancelable and do not contain refund-type provisions. These revenues typically include the following: Encompass Revenues. The Company offers web-based, on-demand access to Encompass software for a monthly recurring fee. The Company provides the right to access its loan origination software and handles the responsibility of managing the servers, providing security, backing up the data and applying updates. Customers under SaaS arrangements do not take possession of the software at any time during the term of the agreement. Subscription revenues are recognized ratably over the contract terms as subscription services are provided, beginning on the commencement date of each contract, which is the date the Company’s service is made available to customers. Contracts generally range from one year to five years . Alternatively, customers can elect to pay on a success basis. Success basis contracts generally have a term of one to five years and are subject to monthly base fees, which enable customers to close loans up to a contractually agreed-to minimum number of transactions, and additional closed loan fees, which are assessed for loans closed in excess of the minimum. Revenues are earned from both base fees and additional closed loan fees as the result of the customer’s usage of Encompass. Monthly base fees are recognized over the respective monthly service period as the subscription services are provided. Additional closed loans fees are recognized when the loans are reported as closed. This offering also includes Encompass Consumer Connect, Encompass Compliance Service, and Encompass Docs Solution as integrated components, which are combined elements of the arrangement that are delivered in conjunction with the Encompass offering and therefore are not accounted for separately. Services Revenues. The Company provides a variety of mortgage-related and other business services, including: automated documentation; fraud detection, valuation, validation, and risk analysis; income verification; marketing and customer relationship management; product and pricing; flood zone certifications; website and electronic document management; and compliance reports. Services revenues are recognized upon completion of the services. Transactional and Other Revenues. The Company has entered into agreements with various lenders, service providers and certain government-sponsored entities participating in the mortgage origination process that provide them access to, and ability to interoperate with, mortgage originators on the Ellie Mae Network. Under these agreements, the Company earns transaction fees when transactions are processed through the Ellie Mae Network. Transactional and other revenues are recognized upon completion of the services. Professional Services Revenues. Professional services revenues are generally recognized upon delivery or completion for fixed price contracts or as the services are rendered for time and material contracts. The majority of the Company’s professional services contracts are on a fixed price basis. Training revenues are recognized as the services are rendered. Subscriptions to Online Research and Data Resources. The Company provides mortgage originators and underwriters with access to online databases of various federal and state laws and regulations and forms as well as investor product guidelines. Subscription fees are recognized ratably over the subscription term as subscription services are provided, which is typically one year. Multiple Element Arrangements The Company enters into arrangements with multiple elements that generally include multiple subscriptions and professional services. For arrangements with multiple deliverables , the Company evaluates whether the individual deliverables qualify as separate units of accounting. In order to treat deliverables in a multiple-deliverable arrangement as separate units of accounting, the deliverables must have standalone value upon delivery. Subscription services have standalone value as such services are often sold separately. Additionally, the Company concluded that professional services included in multiple element arrangements also have standalone value. In establishing standalone value, the Company considered the following factors for each professional services agreement: availability of the services from other vendors, the nature of the professional services, and the timing of when the professional services contract was signed in comparison to the subscription service start date. When subscription services agreements involve multiple elements that qualify as separate units of accounting, the Company allocates arrangement consideration to all deliverables at the inception of an arrangement based on the relative selling price method in accordance with the selling price hierarchy, which includes: (i) vendor specific objective evidence (“VSOE”) if it is available; (ii) third-party evidence (“TPE”) if VSOE is not available; and (iii) the best estimate of selling price (“BESP”) if neither VSOE nor TPE is available. The Company has determined that TPE is not a practical alternative as the Company’s go-to-market strategy and offerings contain a significant level of differentiation such that the comparable pricing of services with similar functionality cannot be obtained. Furthermore, the Company is unable to reliably determine what similar competitor services’ selling prices are on a standalone basis. The amount of revenue allocated to delivered items is limited by contingent revenue, if any. The Company has not historically priced its services within a narrow range. As a result, the Company has not been able to establish VSOE for its services. Accordingly, the Company uses its BESP to determine the relative selling price for its services. The objective of BESP is to determine the price at which the Company would transact a sale if the service was sold on a standalone basis. When establishing BESP, the Company reviews company-specific factors used to determine list price and makes adjustments as appropriate to reflect current market conditions and pricing behavior. The Company’s process for establishing list price includes assessing the cost to provide a particular product or service, surveying customers to determine market expectations, analyzing customer demographics, and taking into account similar products and services historically sold by the Company. The Company continues to review the factors used to establish list price and adjusts BESP as necessary.
Deferred Revenues	Deferred Revenues Deferred revenues represent billings or payments received in advance of revenue recognition and is recognized as the revenue recognition criteria are met. Balances consist primarily of prepaid subscription services and professional and training services not yet provided as of the balance sheet date. Deferred revenues that will be recognized during the succeeding 12 month period are recorded as current deferred revenues, and the remaining portion is recorded as other long-term liabilities.
Deferred Commission Expenses	Deferred Commission Expenses Deferred commission expenses are the incremental costs that are directly associated with non-cancelable subscription contracts with customers and consist of sales commissions paid to the Company’s direct sales force. Commissions are calculated based on a percentage of the revenues for the non-cancelable term of subscription contracts, which are typically one to five years . The deferred commission expense amounts are recoverable through the future revenue streams under the non-cancelable customer contracts.
Warranties and Indemnification	Warranties and Indemnification The Company provides a warranty for its software products and services to its customers and accounts for its warranties as a contingent liability. The Company’s software is generally warranted to perform substantially as described in the associated product documentation and to satisfy defined levels of uptime reliability. The Company’s services are generally warranted to be performed consistent with industry standards. The Company has not provided for a warranty accrual as of December 31, 2017 or 2016 . To date, the Company’s product warranty expense has not been significant. The Company generally agrees to indemnify its customers against legal claims that the Company’s software products infringe certain third-party intellectual property rights and accounts for its indemnification obligations as a contingent liability. In addition, the Company may also incur liability under its contracts if it breaches its warranties as well as certain data security and/or confidentiality obligations. To date, the Company has not been required to make any payment resulting from either infringement claims asserted against its customers or from claims in connection with a breach of the data security and/or confidentiality obligations in the Company’s contracts. The Company has not recorded a liability for related costs as of December 31, 2017 or 2016 . The Company has obligations under certain circumstances to indemnify each executive officer and member of the Company’s board of directors against judgments, fines, settlements, and expenses related to claims against such executive officer or director and otherwise to the fullest extent permitted under Delaware law and the Company’s bylaws and certificate of incorporation.
Cost of Revenues	Cost of Revenues The Company’s cost of revenues consists primarily of: salaries and benefits, including stock-based compensation expense; data center operating costs; depreciation on data center computer equipment; amortization of internal-use software and acquired intangible assets such as developed technology and trade names; customer support; professional services associated with implementation of the Company’s software; third-party royalty expenses; and allocated facilities costs.
Research and Development Costs	Research and Development Costs The Company’s research and development expenses consist primarily of: salaries and benefits, including bonuses and stock-based compensation expense; fees to contractors engaged in the development and support of the Ellie Mae Network , Encompass software and other products; and allocated facilities costs. Research and development costs that are not capitalized as internal-use software are expensed as they are incurred.
Advertising Expenses	Advertising Expenses The Company expenses advertising costs as incurred.
Stock-Based Compensation	Stock-Based Compensation The Company recognizes stock-based compensation related to awards granted under its 2009 Stock Option and Incentive Plan (the “ 2009 Plan ”), 2011 Equity Incentive Award Plan (the “ 2011 Plan ”), and Employee Stock Purchase Plan (“ ESPP ”). The Company recognizes compensation expense related to Restricted Stock Units (“ RSUs ”), Performance-Vesting Restricted Stock Units and Performance Awards (“ Performance Awards ”) based on the fair market value of the underlying shares of common stock as of the date of grant. Expense related to the RSUs is recognized on a straight-line basis over the requisite service period of the award, which generally equals the vesting period. Expense related to the Performance Awards and performance-vesting RSUs is recognized under the graded vesting method over the requisite service period of the award, which results in the recognition of a larger portion of the expense during the beginning of the vesting period than in the end of the vesting period. Management evaluates the probability of performance attainment and estimates the probable number of shares of common stock that will be granted and records the expense accordingly, if probable. The Company recognizes compensation expense related to stock option grants that are ultimately expected to vest based on estimated fair values on the date of grant using the Black-Scholes option-pricing model. Such expense is recognized on a straight-line basis over the requisite service period of the award, which generally equals the vesting period. The date of grant is the date at which the Company and the employee reach a mutual understanding of the key terms and conditions of the award, appropriate approvals are received by the equity incentive committee of the board of directors and the Company becomes contingently obligated to issue equity instruments to the employee who renders the requisite service . The Company estimates potential forfeitures of stock grants and adjust recorded compensation cost accordingly. The estimate of forfeitures is based on historical experience and is adjusted over the requisite service period to the extent that actual forfeitures differ, or are expected to differ, from the prior estimates. Changes in estimated forfeitures will be recognized in the period of change and will impact the amount of stock-based compensation expense to be recognized in future periods .
Income Taxes	Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of taxes payable or refundable for the current year, and deferred tax liabilities and assets for the future tax consequences of events that have been recognized in our financial statements or tax returns. The measurement of current and deferred tax liabilities and assets is based on provisions of the enacted tax law. The Company operates in various tax jurisdictions and is subject to audit by various tax authorities. The Company recognizes the tax benefit of an uncertain tax position only if it is more likely than not that the position is sustainable upon examination by the taxing authority, based on the technical merits. The tax benefit recognized is measured as the largest amount of benefit which is greater than 50 percent likely to be realized upon settlement with the taxing authority. The Company recognizes interest accrued and penalties related to unrecognized tax benefits in the income tax provision. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts that are more likely than not expected to be realized based on the weighting of positive and negative evidence. Future realization of deferred tax assets ultimately depends on estimates of future sources of taxable income for the jurisdictions in which the Company operates and the periods over which the deferred tax assets will be realizable. To the extent the Company establishes a valuation allowance or change the valuation allowance in a period, the Company reflects the change with a corresponding increase or decrease to the tax provision in the consolidated statements of operations. In relation to the Company’s adoption of ASU No. 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), on January 1, 2017, the Company records excess tax benefits and tax deficiencies as an income tax benefit or expense when stock awards vested or settled and, on a retrospective basis, the excess tax benefits are classified as an operating activity in the Company’s consolidated statements of cash flows.
Comprehensive Income	Comprehensive Income Comprehensive income consists of net income and other comprehensive income . Other comprehensive income includes certain changes in equity that are excluded from net income, specifically unrealized gains (losses) on marketable securities. Except for net realized gain (loss) on investments which was not significant, there were no reclassifications out of accumulated other comprehensive income that affected net income during the years ended December 31, 2017 , 2016 and 2015 .
Geographical Information	Geographical Information The Company is domiciled in the United States, had no international operations and had minimal sales to customers outside of the United States for the years ended December 31, 2017, 2016 and 2015 .
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09” or “Topic 606”), as subsequently amended, which outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. This standard requires expanded disclosures about revenue recognition to better communicate the nature, amount, timing, and uncertainty of the Company’s revenue and cash flows, including significant judgments. The standard also provides guidance on the recognition of costs related to obtaining customer contracts. The effective date for public entities is fiscal years beginning after December 15, 2017 and early adoption is allowed. The Company adopted the new standard as of January 1, 2018. The guidance permits two methods of adoption: retrospectively to each prior reporting period presented (full retrospective method), or retrospectively with the cumulative effect of initially applying the guidance recognized at the date of initial application (modified retrospective method). The Company will adopt the standard using the modified retrospective method and is in the process of finalizing the evaluation of the new standard on its accounting policies, processes, and systems including impacts from guidance issued by the FASB Transition Resource Group. The Company has assigned internal resources, engaged a third-party service provider, is in the process of updating its systems and is currently evaluating the quantitative impact to its financial statements. The Company expects an impact to its Encompass subscription and professional services revenue streams due to the removal of the current limitation on contingent revenue, which may affect the timing and allocation of revenue being recognized for certain contracts, and is in the process of finalizing this evaluation. The Company has also identified potential impacts to the costs to obtain customer contracts, which is primarily comprised of sales commissions and the related fringe benefits associated with non-cancelable contracts. The Company is evaluating the quantitative impact of capitalizing the costs to obtain and the costs to fulfill open contracts. The Company expects to capitalize certain costs that are expensed under the current standard, and the Company expects an increase in the amortization period over which the capitalized costs will be recognized. The Company is in the process of finalizing the evaluation of the expected period of benefit under ASU 2014-09. The Company is in the process of finalizing the impact evaluation of the new standard, as subsequently amended, together with the implementation of new accounting systems and processes, which will significantly change the Company’s internal controls over revenue recognition. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU 2016-01”), which updates certain aspects of recognition, measurement, presentation and disclosure of financial instruments. ASU 2016-01 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and early adoption is not permitted. The Company adopted the new standard as of January 1, 2018 and it did not have a material impact on its consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), as subsequently amended, which requires lessees to put most leases on their balance sheets but recognize the expenses on their income statements in a manner similar to current practice. ASU 2016-02 states that a lessee would recognize a lease liability for the obligation to make lease payments and a right-to-use asset for the right to use the underlying asset for the lease term. The standard is effective for interim and annual periods beginning after December 15, 2018, and early adoption is permitted. The Company currently does not intend to early adopt and is evaluating the impact of this accounting standard update on its consolidated financial statements. In May 2017, the FASB issued ASU 2017-09, Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting (“ASU 2017-09”), which provides guidance on determining which changes to the terms and conditions of share-based payment awards require an entity to apply modification accounting under Topic 718. ASU 2017-09 is effective for interim and annual periods beginning after December 15, 2017, and early adoption is permitted. The Company adopted the new standard as of January 1, 2018 and it did not have a material impact on its consolidated financial statements. Standards Adopted In March 2016, the FASB issued ASU 2016-09, which simplifies and makes several modifications to Topic 718 related to the accounting for share-based payment transactions. The standard requires companies to record excess tax benefits and tax deficiencies as income tax benefit or expense in the income statement when stock awards vest or are settled. This change is required to be applied prospectively. The standard also allows the employer tax withholding on share-based compensation to increase (up to the employee’s maximum statutory rates) without triggering liability accounting and provides an accounting policy election to allow the recognition of forfeitures when they are incurred. The standard is effective for interim and annual reporting periods beginning after December 15, 2016, and early adoption is permitted. The Company has adopted the standard as of January 1, 2017. Upon adoption, the Company recognized the previously unrecognized excess tax benefits using the modified retrospective transition method, which resulted in a cumulative-effect adjustment of $18.2 million t o retained earnings as of the beginning of the period. The Company previously reported an adjustment of $14.5 million in its beginning retained earnings for the period ending March 31, 2017, and has corrected this amount as of the beginning of the period in the accompanying consolidated financial statements, as the Company identified an incorrect calculation in the previously reported amount. The correction also has the effect of reducing the Company’s Other long-term liabilities by $2.4 million and increasing Deposits and other assets by $1.3 million . The Company also elected to continue estimating forfeitures and has also elected to apply the change in presentation to the statements of cash flows retrospectively. This resulted in a $10.2 million and $11.4 million increase in net cash provided by operating activities and a corresponding $10.2 million and $11.4 million decrease in net cash provided by (used in) financing activities for the years ended December 31, 2016 and 2015 , respectively, from previously reported amounts. In January 2017, the FASB issued ASU 2017-04. The standard eliminates Step 2 from the goodwill impairment test, which requires a hypothetical purchase price allocation. The Company will continue to have the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. The standard is effective for interim and annual periods beginning after December 15, 2019 and early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The standard should be applied on a prospective basis. The Company elected to early adopt the standard as of January 1, 2017. The adoption did not have an impact to the Company’s consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business . This standard clarifies the definition of a business and is intended to help companies evaluate whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The standard is effective for interim and annual periods beginning after December 15, 2017 and early adoption is permitted under certain circumstances. The standard should be applied prospectively as of the beginning of the period of adoption. The Company elected to early adopt the standard on April 1, 2017. The adoption did not have an impact to the Company’s consolidated financial statements.

Basis of Presentation and Sig22

Basis of Presentation and Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Schedule of Estimated Useful Lives of Intangible Assets	Intangible assets are stated at cost less accumulated amortization. Intangible assets include developed technology, trade names, customer relationships, and order backlog. Intangible assets with finite lives are amortized on a straight-line basis over the estimated periods of benefit, as follows: Developed technology 2-8 years Trade names with finite lives 2-3 years Customer relationships 4-10 years Order backlog 1 year

Net Income Per Share of Commo23

Net Income Per Share of Common Stock (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Schedule of components of net income (loss) per share of common stock	The components of net income per share of common stock were as follows: Year ended December 31, 2017 2016 2015 (in thousands, except share and per share amounts) Net income $ 52,850 $ 37,776 $ 22,258 Weighted average common shares outstanding used to compute basic net income per share 34,056,962 31,179,857 29,179,352 Effect of potentially dilutive securities: Employee stock options, RSUs, performance-vesting RSUs, Performance Awards and ESPP shares 1,748,562 1,619,928 1,663,232 Weighted average common shares outstanding used to compute diluted net income per share 35,805,524 32,799,785 30,842,584 Net income per share: Basic $ 1.55 $ 1.21 $ 0.76 Diluted $ 1.48 $ 1.15 $ 0.72
Schedule of common shares excluded from computation of diluted net income (loss) per share	The following potential weighted average common shares were excluded from the computation of diluted net income per share, as their effect would have been anti-dilutive: Year ended December 31, 2017 2016 2015 Employee stock options and awards 212,257 48,374 225,122

Financial Instruments and Fai24

Financial Instruments and Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2017
Financial Instruments and Fair Value Measurements [Abstract]
Carrying amounts and estimated fair value of cash and cash equivalents and short-term investments	The following table summarizes cash and investments in financial instruments that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy by investment type: December 31, 2017 December 31, 2016 (1) Amortized Cost Unrealized Gains Unrealized Losses Carrying or Fair Value Amortized Unrealized Gains Unrealized Losses Carrying or (in thousands) (in thousands) Cash $ 119,035 $ — $ — $ 119,035 $ 76,538 $ — $ — $ 76,538 Level 1: Money market funds 3,623 — — 3,623 2,733 — — 2,733 U.S. government and government agency obligations 52,255 — (266 ) 51,989 156,240 2 (3 ) 156,239 174,913 — (266 ) 174,647 235,511 2 (3 ) 235,510 Level 2: Corporate notes and obligations 81,062 — (304 ) 80,758 28,978 1 (87 ) 28,892 Certificates of deposit 6,527 2 — 6,529 12,094 13 (19 ) 12,088 Municipal obligations 10,274 — (46 ) 10,228 11,422 1 (62 ) 11,361 U.S. government and government agency obligations 76,510 — (266 ) 76,244 180,893 14 (79 ) 180,828 Total financial instruments 349,286 2 (882 ) 348,406 468,898 31 (250 ) 468,679 Less investments 211,588 2 (882 ) 210,708 87,996 23 (247 ) 87,772 Cash and cash equivalents $ 137,698 $ — $ — $ 137,698 $ 380,902 $ 8 $ (3 ) $ 380,907 ________________ (1) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements.
Gross unrealized losses and the related fair values of investments in a continuous unrealized loss position	The following table shows the gross unrealized losses and the related fair values of the Company’s investments that have been in a continuous unrealized loss position. The Company did not identify any investments as other-than-temporarily impaired at December 31, 2017 or December 31, 2016 based on its evaluation of available evidence, such as whether it is the Company’s intent to hold an investment to its contractual maturity date and whether it is more likely than not that the Company will be required to sell the investment before recovery of the investment’s amortized basis. The Company typically expects to receive the full principal and interest on its investments. December 31, 2017 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands) Corporate notes and obligations $ 62,099 $ (253 ) $ 7,574 $ (51 ) $ 69,673 $ (304 ) Certificates of deposit 482 — 1,348 — 1,830 — U.S. government, government agency, and municipal obligations 119,456 (492 ) 13,070 (86 ) 132,526 (578 ) Total $ 182,037 $ (745 ) $ 21,992 $ (137 ) $ 204,029 $ (882 ) December 31, 2016 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands) Corporate notes and obligations $ 26,076 $ (87 ) $ — $ — $ 26,076 $ (87 ) Certificates of deposit 5,651 (19 ) — — 5,651 (19 ) U.S. government, government agency, and municipal obligations 180,138 (144 ) 385 — 180,523 (144 ) Total $ 211,865 $ (250 ) $ 385 $ — $ 212,250 $ (250 )
Summary of the maturities of the Company's investments	The following table summarizes the contractual maturities of the Company’s investments at December 31, 2017 : Amortized Cost Carrying or Fair Value (in thousands) Due within one year $ 103,508 $ 103,345 Due after one year through three years (1) 108,080 107,363 Total $ 211,588 $ 210,708 ________________ (1) Maximum maturity of individual investments is three years.

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Schedule of Purchase Consideration Allocation	The allocation of the purchase consideration to the identifiable tangible and intangible assets acquired and liabilities assumed under the purchase method of accounting, based on their estimated fair values as of the acquisition date, is summarized in the following table (in thousands): Cash and cash equivalents $ 10,686 Other assets 3,510 Property and equipment 843 Identifiable intangible assets 73,100 Current liabilities (5,280 ) Deferred tax liability (21,206 ) Deferred revenue (1,600 ) Goodwill 69,904 Total purchase consideration $ 129,957
Schedule of Intangible Assets Acquired	The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the date of acquisition. Fair Value Useful Life (in thousands) (in years) Developed technology $ 42,000 8.0 Customer relationships 15,500 10.0 Order backlog 14,000 1.0 Trade name 1,600 3.0 Identifiable intangible assets $ 73,100

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The change in the carrying value of goodwill during the period ended December 31, 2017 was as follows (in thousands): Balance at December 31, 2015 $ 74,547 No changes — Balance at December 31, 2016 74,547 Addition: Velocify acquisition 69,904 Balance at December 31, 2017 $ 144,451
Schedule of Finite-Lived Intangible Assets	Intangible assets, net, consisted of the following: December 31, 2017 Gross carrying Accumulated Net intangibles Weighted Average Remaining Useful Life (in thousands) (in years) Assets subject to amortization: Developed technology $ 53,535 $ (10,810 ) $ 42,725 7.5 Trade names 1,931 (464 ) 1,467 2.8 Customer relationships 34,900 (13,050 ) 21,850 7.7 Order backlog 14,370 (3,577 ) 10,793 0.8 Total assets subject to amortization 104,736 (27,901 ) 76,835 6.5 Assets not subject to amortization: Trade name 4,039 — 4,039 Total intangible assets $ 108,775 $ (27,901 ) $ 80,874 December 31, 2016 Gross carrying Accumulated Net intangibles Weighted Average Remaining Useful Life (in thousands) (in years) Assets subject to amortization: Developed technology $ 11,535 $ (8,183 ) $ 3,352 2.7 Trade names 331 (331 ) — 0.0 Customer relationships 19,400 (9,762 ) 9,638 4.0 Order backlog 370 (110 ) 260 2.8 Total assets subject to amortization 31,636 (18,386 ) 13,250 3.6 Assets not subject to amortization: Trade name 4,039 — 4,039 Total intangible assets $ 35,675 $ (18,386 ) $ 17,289
Schedule of Indefinite-Lived Intangible Assets	Intangible assets, net, consisted of the following: December 31, 2017 Gross carrying Accumulated Net intangibles Weighted Average Remaining Useful Life (in thousands) (in years) Assets subject to amortization: Developed technology $ 53,535 $ (10,810 ) $ 42,725 7.5 Trade names 1,931 (464 ) 1,467 2.8 Customer relationships 34,900 (13,050 ) 21,850 7.7 Order backlog 14,370 (3,577 ) 10,793 0.8 Total assets subject to amortization 104,736 (27,901 ) 76,835 6.5 Assets not subject to amortization: Trade name 4,039 — 4,039 Total intangible assets $ 108,775 $ (27,901 ) $ 80,874 December 31, 2016 Gross carrying Accumulated Net intangibles Weighted Average Remaining Useful Life (in thousands) (in years) Assets subject to amortization: Developed technology $ 11,535 $ (8,183 ) $ 3,352 2.7 Trade names 331 (331 ) — 0.0 Customer relationships 19,400 (9,762 ) 9,638 4.0 Order backlog 370 (110 ) 260 2.8 Total assets subject to amortization 31,636 (18,386 ) 13,250 3.6 Assets not subject to amortization: Trade name 4,039 — 4,039 Total intangible assets $ 35,675 $ (18,386 ) $ 17,289
Schedule of Future Amortization Expense	Minimum future amortization expense for intangible assets at December 31, 2017 was as follows (in thousands): 2018 $ 20,951 2019 10,549 2020 9,028 2021 7,164 2022 7,105 Thereafter 22,038 $ 76,835

Other Balance Sheet Components

Other Balance Sheet Components (Tables)	12 Months Ended
	Dec. 31, 2017
Statement of Financial Position [Abstract]
Prepaid Expenses and Other Assets	Prepaid expenses and other current assets consisted of the following: December 31, 2017 2016 (in thousands) Prepaid expenses $ 13,494 $ 11,568 Deferred commissions, current portion 3,533 2,761 Other current assets 1,447 880 $ 18,474 $ 15,209
Property and Equipment	Property and equipment, net, consisted of the following: December 31, 2017 2016 (in thousands) Computer equipment and software $ 67,068 $ 54,029 Internal-use software (1) 108,710 62,573 Furniture and fixtures 8,311 6,838 Leasehold improvements 27,356 18,532 Internal-use software and other assets not yet placed in service 52,659 33,316 Property and equipment, gross 264,104 175,288 Accumulated depreciation and amortization (77,113 ) (48,991 ) Property and equipment, net $ 186,991 $ 126,297 ________________ (1) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements.
Accrued and Other Current Liabilities	Accrued and other current liabilities consisted of the following: December 31, 2017 2016 (in thousands) Accrued payroll and related expenses $ 18,018 $ 31,848 Accrued commissions 1,480 1,832 Accrued royalties 1,630 1,395 Sales and other taxes 1,737 2,327 Other accrued expenses (1) 3,323 2,407 $ 26,188 $ 39,809
Deferred Revenue	Deferred revenues consisted of the following: December 31, 2017 2016 (in thousands) Professional services and training $ 11,350 $ 10,729 Subscriptions 10,565 8,419 Other 4,772 4,140 Total 26,687 23,288 Less portion included in other long-term liabilities (400 ) (162 ) $ 26,287 $ 23,126 Other Long-Term Liabilities Other long-term liabilities consisted of the following: December 31, 2017 2016 (in thousands) Deferred revenue $ 400 $ 162 Deferred rent 13,443 9,512 Deferred tax liability 4,963 5,564 Other long-term liabilities (1) 74 2,494 $ 18,880 $ 17,732 ________________ (1) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The components of the provision for income taxes were as follows: Year ended December 31, 2017 2016 2015 (in thousands) Current Federal $ 156 $ 9,428 $ 8,070 State 305 1,664 1,894 461 11,092 9,964 Deferred Federal (11,793 ) 7,124 1,899 State 3,876 614 356 (7,917 ) 7,738 2,255 Income tax provision (benefit) $ (7,456 ) $ 18,830 $ 12,219
Schedule of Effective Income Tax Rate Reconciliation	The provision for income taxes differed from the amount of income taxes determined by applying the U.S. statutory federal income tax rate as follows: Year ended December 31, 2017 2016 2015 Tax at federal statutory rate 35 % 35 % 35 % State taxes, net of federal benefit 7 4 5 Excess tax benefits related to stock-based compensation (1) (35 ) 1 1 Research and development tax credits (12 ) (6 ) (7 ) Re-measurement of net deferred tax liabilities arising from The Tax Act (19 ) — — Other non-deductible items (2) 4 — 1 Other 4 (1 ) — Income tax provision (benefit) (16 )% 33 % 35 % ________________ (1) In 2017, due to the adoption of ASU 2016-09, the excess tax benefits resulted from the vesting or the settlement of the stock awards were recorded in the tax provision. (2) Certain reclassifications of prior period amounts have been made to conform to the current period presentation, such reclassification did not materially change previously reported consolidated financial statements.
Schedule of Deferred Tax Assets and Liabilities	The components of net deferred tax assets (liabilities) were as follows: December 31, 2017 2016 (in thousands) Deferred tax assets Research and development credits $ 29,461 $ 5,089 Stock-based compensation 8,765 12,551 Reserves and accruals 5,894 11,896 Net operating loss carryforwards 16,422 — Total deferred tax assets 60,542 29,536 Valuation allowance (11,908 ) (5,089 ) Total deferred tax assets, net of valuation allowance 48,634 24,447 Deferred tax liabilities Depreciation and amortization (50,360 ) (28,749 ) Book/tax basis in acquired assets (1,360 ) (1,262 ) Total deferred tax liabilities (51,720 ) (30,011 ) Net deferred tax liabilities $ (3,086 ) $ (5,564 )
Schedule of Unrecognized Tax Benefits	A reconciliation of the beginning and ending balance of gross unrecognized tax benefits is as follows for the periods indicated: Year ended December 31, 2017 2016 2015 (in thousands) Beginning balance $ 4,634 $ 3,440 $ 2,408 Additions based on tax positions related to the current year 5,420 1,334 1,023 Additions (reductions) based on tax positions related to prior years including acquisitions (26 ) (140 ) 9 Ending balance $ 10,028 $ 4,634 $ 3,440

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments for Capital and Operating Leases	Future minimum lease payments under non-cancelable operating and capital leases at December 31, 2017 consisted of the following: Capital Leases Operating Leases (in thousands) 2018 $ 87 $ 11,718 2019 — 12,349 2020 — 12,025 2021 — 11,306 2022 — 11,484 Thereafter — 34,363 Total minimum lease payments 87 $ 93,245 Less amount representing interest (2 ) Present value of minimum lease payments 85 Less current portion (85 ) Long-term portion of lease obligations $ —

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Schedule of shares of common stock reserved and available for future issuance	The following number of shares of common stock were reserved and available for future issuance at December 31, 2017 : Reserved Shares Options and awards granted and outstanding under stock incentive plans 2,909,953 Shares available for future grant under the stock incentive plans 5,140,367 Shares available under the employee stock purchase plan 1,614,689 Total 9,665,009
Schedule of Share Repurchases	The Company repurchased the following shares of common stock under its repurchase programs: Shares Repurchased Weighted Average Purchase Price per Share Total Amount (in thousands) Year Ended 2017 401,188 $ 87.85 $ 35,244 Year Ended 2016 8,333 $ 79.62 $ 663 Year Ended 2015 503,450 $ 62.63 $ 31,530

Share-based Compensation (Table

Share-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Company's stock option activities	The following table summarizes the Company’s stock option activity under the 2009 Plan and 2011 Plan: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (in years) (in thousands) Outstanding at December 31, 2014 3,050,301 $ 17.41 Granted 385,776 $ 55.30 Exercised (822,133 ) $ 12.28 Forfeited or expired (98,615 ) $ 30.12 Outstanding at December 31, 2015 2,515,329 $ 24.40 Granted 14,506 $ 59.78 Exercised (584,807 ) $ 18.08 Forfeited or expired (59,696 ) $ 37.94 Outstanding at December 31, 2016 1,885,332 $ 26.21 Granted 6,601 $ 94.66 Exercised (432,341 ) $ 23.61 Forfeited or expired (23,561 ) $ 40.94 Outstanding at December 31, 2017 1,436,031 $ 27.06 5.43 $ 89,554 Ending vested and expected to vest at December 31, 2017 1,431,645 $ 26.98 5.42 $ 89,393 Exercisable at December 31, 2017 1,250,119 $ 24.05 5.18 $ 81,700
Stock options activity, additional information	Following is additional information pertaining to the Company’s stock option activity: Year ended December 31, 2017 2016 2015 (in thousands except for per option data) Weighted average fair value per option granted $ 45.44 $ 27.57 $ 26.13 Grant-date fair value of options vested $ 4,994 $ 8,577 $ 8,285 Intrinsic value of options exercised $ 31,621 $ 39,040 $ 38,971 Proceeds received from options exercised $ 10,208 $ 10,573 $ 10,094
Summary of RSU activities	The following table summarizes the Company’s RSU, Performance Award and performance-vesting RSU activity: RSUs Performance Awards and performance-vesting RSUs Number of Shares Weighted Average Grant Date Fair Value Per Share Number of Shares Weighted Average Grant Date Fair Value Per Share Outstanding at December 31, 2014 585,858 $ 27.20 485,177 $ 25.61 Granted 401,158 $ 62.62 205,816 $ 47.18 Released (179,530 ) $ 25.97 (182,711 ) $ 24.69 Forfeited or expired (58,798 ) $ 39.40 — $ — Outstanding at December 31, 2015 748,688 $ 45.52 508,282 $ 34.68 Granted 598,390 $ 78.39 151,540 $ 61.69 Released (240,386 ) $ 42.48 (239,120 ) $ 29.34 Forfeited or expired (81,577 ) $ 57.50 (13,052 ) $ 68.19 Outstanding at December 31, 2016 1,025,115 $ 64.47 407,650 $ 46.77 Granted 651,936 $ 97.73 43,414 $ 94.66 Released (355,045 ) $ 57.37 (150,727 ) $ 40.73 Forfeited or expired (142,548 ) $ 82.25 (5,873 ) $ 84.86 Outstanding at December 31, 2017 1,179,458 $ 82.84 294,464 $ 56.17 Ending vested and expected to vest at December 31, 2017 1,034,136 294,463
Schedule of valuation assumptions	The fair value of stock options and stock purchase rights granted under the 2009 Plan, the 2011 Plan and the ESPP were estimated at the date of grant using the Black-Scholes option valuation model with the following weighted average assumptions: Year ended December 31, 2017 2016 2015 Stock option plans: Risk-free interest rate 2.04 % 1.38 % 1.50-1.96 % Expected life of options (in years) 6.08 6.08 5.00-6.08 Expected dividend yield — % — % — % Volatility 48 % 47 % 48-49 % Employee Stock Purchase Plan: Risk-free interest rate 0.46-0.69 % 0.46-0.48 % 0.13-0.24 % Expected life of options (in years) 0.5 0.5 0.5 Expected dividend yield — % — % — % Volatility 33-37 % 33-49 % 35-44 %
Stock-based compensation expense	Total stock-based compensation expense recognized by the Company consisted of: Year ended December 31, 2017 2016 2015 (in thousands) Stock-based compensation by category of expense: Cost of revenues $ 6,786 $ 4,835 $ 3,218 Sales and marketing 5,223 4,429 2,752 Research and development 8,281 7,296 5,431 General and administrative 14,177 14,911 12,840 $ 34,467 $ 31,471 $ 24,241

Quarterly Results of Operatio32

Quarterly Results of Operations Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	Three months ended Dec 31, Sep 30, Jun 30, Mar 31, Dec 31, Sep 30, Jun 30, Mar 31, (in thousands, except per share amounts) Revenues $ 112,886 $ 107,029 $ 104,125 $ 93,002 $ 96,181 $ 100,381 $ 90,098 $ 73,625 Gross profit $ 64,614 $ 67,426 $ 65,858 $ 58,234 $ 63,338 $ 68,163 $ 61,645 $ 46,994 Income before income taxes $ 3,417 $ 18,984 $ 17,987 $ 5,006 $ 14,766 $ 21,272 $ 16,846 $ 3,722 Net income $ 9,909 $ 14,519 $ 18,823 $ 9,599 $ 10,902 $ 13,780 $ 10,588 $ 2,506 Net income per share, basic $ 0.29 $ 0.42 $ 0.55 $ 0.28 $ 0.33 $ 0.43 $ 0.36 $ 0.09 Net income per share, diluted $ 0.28 $ 0.41 $ 0.52 $ 0.27 $ 0.31 $ 0.41 $ 0.34 $ 0.08

Basis of Presentation and Sig33

Basis of Presentation and Significant Accounting Policies (Details Textual)	12 Months Ended
	Dec. 31, 2017USD ($)segment	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Basis of Presentation and Significant Accounting Policies [Line Items]
Number of reporting segments | segment	1
Capitalized software and website application development costs	$ 64,600,000	$ 38,500,000	$ 29,400,000
Commission expenses deferred	4,300,000	4,900,000	3,600,000
Deferred commission balance	8,500,000	7,800,000
Advertising expenses	1,300,000	1,000,000	700,000
Reclassification from accumulated other comprehensive income to net income	$ 0	$ 0	$ 0
Minimum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Property and equipment, useful life	3 years
SaaS contract agreements maturity period	1 year
Success basis contract period	1 year
Maximum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Property and equipment, useful life	7 years
SaaS contract agreements maturity period	5 years
Success basis contract period	5 years
Developed technology | Minimum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Intangible asset, useful life	2 years
Developed technology | Maximum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Intangible asset, useful life	8 years
Trade name | Minimum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Intangible asset, useful life	2 years
Trade name | Maximum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Intangible asset, useful life	3 years
Customer relationships | Minimum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Intangible asset, useful life	4 years
Customer relationships | Maximum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Intangible asset, useful life	10 years
Order backlog
Basis of Presentation and Significant Accounting Policies [Line Items]
Intangible asset, useful life	1 year
Internal-use software | Minimum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Property and equipment, useful life	3 years
Internal-use software | Maximum [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Property and equipment, useful life	5 years

Basis of Presentation and Sig34

Basis of Presentation and Significant Accounting Policies (Standards Adopted) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jan. 01, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Cumulative-effect adjustment		$ 18,244
Other long-term liabilities		18,880	$ 17,732
Deposits and other assets		9,290	10,138
Net cash provided by operating activities		116,221	112,899	$ 98,617
Net cash provided by (used in) financing activities		(30,398)	278,210	(24,628)
ASU No. 2016-09 [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Cumulative-effect adjustment	$ 14,500	$ 18,200
ASU No. 2016-09 [Member] | Reclassification [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other long-term liabilities					$ (2,400)
Deposits and other assets					$ 1,300
Net cash provided by operating activities			10,200	11,400
Net cash provided by (used in) financing activities			$ (10,200)	$ (11,400)

Net Income Per Share of Commo35

Net Income Per Share of Common Stock (Components of Net Income Per Share) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components of net income (loss) per share of common stock
Net income	$ 9,909,000	$ 14,519,000	$ 18,823,000	$ 9,599,000	$ 10,902,000	$ 13,780,000	$ 10,588,000	$ 2,506,000	$ 52,850,000	$ 37,776,000	$ 22,258,000
Basic shares:
Weighted average common shares outstanding									34,056,962	31,179,857	29,179,352
Diluted shares:
Weighted average common shares outstanding									34,056,962	31,179,857	29,179,352
Effect of potentially dilutive securities:
Warrants to purchase common stock, employee stock options, RSUs and convertible preferred stock									1,748,562	1,619,928	1,663,232
Weighted average shares used to compute diluted net income per share									35,805,524	32,799,785	30,842,584
Net income (loss) per share:
Basic (USD per share)	$ 0.29	$ 0.42	$ 0.55	$ 0.28	$ 0.33	$ 0.43	$ 0.36	$ 0.09	$ 1.55	$ 1.21	$ 0.76
Diluted (USD per share)	$ 0.28	$ 0.41	$ 0.52	$ 0.27	$ 0.31	$ 0.41	$ 0.34	$ 0.08	$ 1.48	$ 1.15	$ 0.72

Net Income Per Share of Commo36

Net Income Per Share of Common Stock (Anti-Dilutive Shares) (Details) - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Stock Options and Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	212,257	48,374	225,122
Performance Based Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	15,954	20,304	0

Financial Instruments and Fai37

Financial Instruments and Fair Value Measurement (Investments in Financial Instruments Measured at Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Cash	$ 119,035	$ 76,538
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	211,588	87,996
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	2	23
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(882)	(247)
Available-for-sale Securities	210,708	87,772
Cash and cash equivalents	137,698	380,907	$ 34,396	$ 26,756
Cash and cash equivalents
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Cash And Cash Equivalents, Amortized Cost Basis	137,698	380,902
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	8
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	(3)
Cash and cash equivalents	137,698	380,907
Fair Value, Measurements, Recurring | Investments [Member]
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	349,286	468,898
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	2	31
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(882)	(250)
Available-for-sale Securities	348,406	468,679
Fair Value, Measurements, Recurring | Level 1
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	174,913	235,511
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	2
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(266)	(3)
Available-for-sale Securities	174,647	235,510
Fair Value, Measurements, Recurring | Level 1 | Money market funds
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	3,623	2,733
Available-for-sale Securities	3,623	2,733
Fair Value, Measurements, Recurring | Level 1 | U.S. government and government agency obligations
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	52,255	156,240
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	2
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(266)	(3)
Available-for-sale Securities	51,989	156,239
Fair Value, Measurements, Recurring | Level 2 | Corporate note and obligations
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	81,062	28,978
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	1
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(304)	(87)
Available-for-sale Securities	80,758	28,892
Fair Value, Measurements, Recurring | Level 2 | Certificates of deposit
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	6,527	12,094
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	2	13
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	(19)
Available-for-sale Securities	6,529	12,088
Fair Value, Measurements, Recurring | Level 2 | Municipal obligations
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	10,274	11,422
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	1
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(46)	(62)
Available-for-sale Securities	10,228	11,361
Fair Value, Measurements, Recurring | Level 2 | U.S. government and government agency obligations
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax [Abstract]
Available-for-sale Securities, Amortized Cost Basis	76,510	180,893
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	14
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(266)	(79)
Available-for-sale Securities	$ 76,244	$ 180,828

Financial Instruments and Fai38

Financial Instruments and Fair Value Measurement (Interest Income and Continuous Unrealized Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financial Instruments and Fair Value Measurements [Abstract]
Interest income from financial instruments	$ 3,300	$ 1,100	$ 700
Continuous Unrealized Loss Position [Abstract]
Less than 12 Months, Fair Value	182,037	211,865
Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	745	250
12 Months or Greater, Fair Value	21,992	385
Continuous Unrealized Loss Position, 12 Months or Greater, Accumulated Loss	137	0
Fair Value	204,029	212,250
Continuous Unrealized Position, Accumulated Loss	882	250
Corporate note and obligations
Continuous Unrealized Loss Position [Abstract]
Less than 12 Months, Fair Value	62,099	26,076
Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	253	87
12 Months or Greater, Fair Value	7,574	0
Continuous Unrealized Loss Position, 12 Months or Greater, Accumulated Loss	51	0
Fair Value	69,673	26,076
Continuous Unrealized Position, Accumulated Loss	304	87
Certificates of deposit
Continuous Unrealized Loss Position [Abstract]
Less than 12 Months, Fair Value	482	5,651
Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	19
12 Months or Greater, Fair Value	1,348	0
Continuous Unrealized Loss Position, 12 Months or Greater, Accumulated Loss	0	0
Fair Value	1,830	5,651
Continuous Unrealized Position, Accumulated Loss	0	19
U.S. government, government agency, and municipal obligations
Continuous Unrealized Loss Position [Abstract]
Less than 12 Months, Fair Value	119,456	180,138
Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	492	144
12 Months or Greater, Fair Value	13,070	385
Continuous Unrealized Loss Position, 12 Months or Greater, Accumulated Loss	86	0
Fair Value	132,526	180,523
Continuous Unrealized Position, Accumulated Loss	$ 578	$ 144

Financial Instruments and Fai39

Financial Instruments and Fair Value Measurement (Contractual Maturities of Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Amortized Cost
Due within one year	$ 103,508
Due after one year through three years	108,080
Total	211,588	$ 87,996
Carrying or Fair Value
Due within one year	103,345
Due after one year through three years	107,363
Total	$ 210,708	$ 87,772

Acquisitions (Details Textual)

Acquisitions (Details Textual) - Velocify Inc - USD ($)	Oct. 02, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Total purcahse consideration	$ 130,000,000
Consideration place in escrow to cover adjustments and claims	$ 16,000,000
Escrow cash paid to seller		$ 0
Maximum time escrow cash is held prior to payment to seller	18 months

Acquisitions (Purchase Price Al

Acquisitions (Purchase Price Allocation) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Oct. 02, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill	$ 144,451		$ 74,547	$ 74,547
Velocify Inc
Business Acquisition [Line Items]
Cash and cash equivalents		$ 10,686
Other assets		3,510
Property and equipment		843
Identifiable intangible assets		73,100
Current liabilities		(5,280)
Deferred tax liability (non-current)		(21,206)
Deferred revenue (non-current)		(1,600)
Goodwill		69,904
Total purchase consideration		$ 129,957

Acquisitions (Identifiable Inta

Acquisitions (Identifiable Intangible Assets) (Details) - Velocify Inc $ in Thousands	Oct. 02, 2017USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets	$ 73,100
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets	$ 42,000
Acquired intangible assets, useful life	96 months
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets	$ 15,500
Acquired intangible assets, useful life	120 months
Order backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets	$ 13,500
Acquired intangible assets, useful life	12 months
Trade name
Acquired Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets	$ 1,600
Acquired intangible assets, useful life	36 months

Goodwill and Intangible Asset43

Goodwill and Intangible Assets (Goodwill Rollforward) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 74,547	$ 74,547
No changes		0
Addition: Velocify acquisition	69,904
Goodwill, ending balance	$ 144,451	$ 74,547

Goodwill and Intangible Asset44

Goodwill and Intangible Assets (Schedule of Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 108,775	$ 35,675
Intangible assets, net	80,874	17,289
Assets subject to amortization:
Finite-lived intangible assets, gross	104,736	31,636
Accumulated amortization	(27,901)	(18,386)
Finite-lived intangible assets, net	$ 76,835	$ 13,250
Weighted average remaining useful life	78 months 5 days	43 months 17 days
Trade name
Assets not subject to amortization:
Indefinite-lived intangible assets	$ 4,039	$ 4,039
Developed technology
Assets subject to amortization:
Finite-lived intangible assets, gross	53,535	11,535
Accumulated amortization	(10,810)	(8,183)
Finite-lived intangible assets, net	$ 42,725	$ 3,352
Weighted average remaining useful life	89 months 18 days	32 months 21 days
Trade name
Assets subject to amortization:
Finite-lived intangible assets, gross	$ 1,931	$ 331
Accumulated amortization	(464)	(331)
Finite-lived intangible assets, net	$ 1,467	$ 0
Weighted average remaining useful life	33 months	0 years
Customer relationships
Assets subject to amortization:
Finite-lived intangible assets, gross	$ 34,900	$ 19,400
Accumulated amortization	(13,050)	(9,762)
Finite-lived intangible assets, net	$ 21,850	$ 9,638
Weighted average remaining useful life	92 months 25 days	47 months 18 days
Order backlog
Assets subject to amortization:
Finite-lived intangible assets, gross	$ 14,370	$ 370
Accumulated amortization	(3,577)	(110)
Finite-lived intangible assets, net	$ 10,793	$ 260
Weighted average remaining useful life	9 months 6 days	34 months

Goodwill and Intangible Asset45

Goodwill and Intangible Assets (Future Amortization Expense) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,018	$ 20,951
2,019	10,549
2,020	9,028
2,021	7,164
2,022	7,105
Thereafter	22,038
Finite-lived intangible assets, net	$ 76,835	$ 13,250

Other Balance Sheet Component46

Other Balance Sheet Components (Prepaid Expenses and Other) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Prepaid Expense and Other Assets [Abstract]
Prepaid expenses	$ 13,494	$ 11,568
Deferred commissions, current portion	3,533	2,761
Other receivables	1,447	880
Prepaid expenses and other current assets	$ 18,474	$ 15,209

Other Balance Sheet Component47

Other Balance Sheet Components (Property and Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	$ 264,104	$ 175,288
Internal-use software and other assets not yet placed in service	52,659	33,316
Accumulated depreciation and amortization	(77,113)	(48,991)
Property and equipment, net	186,991	126,297
Unamortized internal-use software	124,400	77,200
Amortization of internal-use software	17,700	8,300	$ 2,400
Depreciation and amortization	36,482	20,460	10,842
Capital leases amortization expense	2,800	3,200	$ 2,500
Computer equipment and software
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	67,068	54,029
Internal-use software
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	108,710	62,573
Furniture and fixtures
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	8,311	6,838
Leasehold improvements
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	$ 27,356	$ 18,532

Other Balance Sheet Component48

Other Balance Sheet Components (Accrued and Other Current Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Accrued and Other Current Liabilities:
Accrued payroll and related expenses	$ 18,018	$ 31,848
Accrued commissions	1,480	1,832
Accrued royalties	1,630	1,395
Sales and other taxes	1,737	2,327
Other accrued expenses	3,323	2,407
Accrued and other current liabilities	$ 26,188	$ 39,809

Other Balance Sheet Component49

Other Balance Sheet Components (Deferred Revenue) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 26,687	$ 23,288
Less portion included in long-term other liabilities	(400)	(162)
Deferred revenue, current	26,287	23,126
Professional services and training
Deferred Revenue Arrangement [Line Items]
Deferred revenue	11,350	10,729
Subscriptions
Deferred Revenue Arrangement [Line Items]
Deferred revenue	10,565	8,419
Other
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 4,772	$ 4,140

Other Balance Sheet Component50

Other Balance Sheet Components (Other Long-Term Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Deferred revenue	$ 400	$ 162
Deferred rent	13,443	9,512
Deferred tax liability	4,963	5,564
Other long-term liabilities	74	2,494
Other long-term liabilities	$ 18,880	$ 17,732

Income Taxes (Details Textual)

Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Decrease in valuation allowance	$ (6,800)	$ (1,200)	$ (1,000)
Provisional tax benefit adjustment related to the impact of Tax Act rate change on deferred tax liabilities	8,600
Unrecognized tax benefits	10,028	$ 4,634	$ 3,440	$ 2,408
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	5,500
Unrecognized tax benefits netted against deferred tax assets subject to full valuation allowance	$ 4,500

Income Taxes (Components of Inc

Income Taxes (Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Current federal tax expense (benefit)	$ 156	$ 9,428	$ 8,070
Current state and local tax expense (benefit)	305	1,664	1,894
Current income tax expense (benefit)	461	11,092	9,964
Deferred federal income tax expense (benefit)	(11,793)	7,124	1,899
Deferred state and local income tax expense (benefit)	3,876	614	356
Deferred income tax expense (benefit)	(7,917)	7,738	2,255
Income tax provision (benefit)	$ (7,456)	$ 18,830	$ 12,219

Income Taxes (Effective Income

Income Taxes (Effective Income Tax Rate Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Tax at federal statutory rate	35.00%	35.00%	35.00%
State taxes, net of federal benefit	7.00%	4.00%	5.00%
Excess tax benefits related to stock-based compensation	(35.00%)	1.00%	1.00%
Research and development tax credits	(12.00%)	(6.00%)	(7.00%)
Re-measurement of net deferred tax liabilities arising from The Tax Act	(19.00%)	0.00%	0.00%
Other non-deductible items	4.00%	0.00%	1.00%
Other	4.00%	(1.00%)	0.00%
Income tax provision (benefit)	(16.00%)	33.00%	35.00%

Income Taxes (Components of Def

Income Taxes (Components of Deferred Tax Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets
Research and development credits	$ 29,461	$ 5,089
Stock-based compensation	8,765	12,551
Reserves and accruals	5,894	11,896
Net operating loss carryforwards	16,422	0
Gross deferred tax assets	60,542	29,536
Valuation allowance	(11,908)	(5,089)
Net deferred tax assets	48,634	24,447
Deferred tax liabilities
Depreciation and amortization	(50,360)	(28,749)
Book/tax basis in acquired assets	(1,360)	(1,262)
Total deferred tax liabilities	(51,720)	(30,011)
Net deferred tax liabilities	$ (3,086)	$ (5,564)

Income Taxes (Operating Loss Ca

Income Taxes (Operating Loss Carryforwards) (Details) $ in Millions	Dec. 31, 2017USD ($)
Federal [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 68.7
State [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 38.6

Income Taxes (Tax Credit Carryf

Income Taxes (Tax Credit Carryforwards) (Details) - Research and Development Tax Credit Carryforward [Member] $ in Millions	Dec. 31, 2017USD ($)
Federal [Member]
Tax Credit Carryforward [Line Items]
Tax credit carryforward	$ 22
State [Member]
Tax Credit Carryforward [Line Items]
Tax credit carryforward	$ 20.3

Income Taxes (Reconciliation of

Income Taxes (Reconciliation of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Unrecognized tax benefits, beginning balance	$ 4,634	$ 3,440	$ 2,408
(Deductions) additions based on tax positions related to the current year	5,420	1,334	1,023
Additions (reductions) based on tax positions related to prior years including acquisitions	(26)	(140)
Additions based on tax positions related to prior years including acquisitions			9
Unrecognized tax benefits, ending balance	$ 10,028	$ 4,634	$ 3,440

Commitments and Contingencies58

Commitments and Contingencies (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)facility	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
Facilities under operating lease arrangements | facility	9
Rent expense	$ 7.9	$ 5.4	$ 4.2
Total purchase commitments	66.6
Purchase commitments due in 2018	39.7
Purchase commitments due in 2019	25
Purchase commitments due in 2020	$ 1.8

Commitments and Contingencies59

Commitments and Contingencies (Future Minimum Lease Payments) (Details) $ in Thousands	Dec. 31, 2017USD ($)
Capital Leases
2,018	$ 87
2,019	0
2,020	0
2,021	0
2,022	0
Thereafter	0
Total minimum lease payments	87
Less amount representing interest	(2)
Present value of minimum lease payments	85
Less current portion	(85)
Long-term portion of lease obligations	0
Operating Leases
2,018	11,718
2,019	12,349
2,020	12,025
2,021	11,306
2,022	11,484
Thereafter	34,363
Total minimum lease payments	$ 93,245

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Apr. 20, 2011
Class of Stock [Line Items]
Common stock, shares authorized		140,000,000	140,000,000	140,000,000
Common stock, par value		$ 0.0001000	$ 0.0001000	$ 0.0001
Preferred stock, shares authorized				10,000,000
Preferred stock, par value				$ 0.0001
Shares of common stock reserved and available for future issuance		9,665,009
Issuance of common stock in public offering, net of issuance costs, shares	3,162,500
Issuance of common stock in public offering, net of issuance costs	$ 271,400		$ 271,309
Payments of Stock Issuance Costs	$ 13,200	$ 15
Options and Awards Outstanding [Member]
Class of Stock [Line Items]
Shares of common stock reserved and available for future issuance		2,909,953
Shares Available for Future Grant [Member]
Class of Stock [Line Items]
Shares of common stock reserved and available for future issuance		5,140,367
Shares Available Under Employee Stock Purchase Plan [Member]
Class of Stock [Line Items]
Shares of common stock reserved and available for future issuance		1,614,689

Stockholders' Equity (Share Rep

Stockholders' Equity (Share Repurchase Program) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Aug. 31, 2017	May 31, 2014
Equity [Abstract]
Stock repurchase program, authorized amount				$ 250,000	$ 75,000
Shares Repurchased Under Repurchase Program:
Shares Repurchased	401,188	8,333	503,450
Weighted Average Purchase Price per Share	$ 87.85	$ 79.62	$ 62.63
Total Amount	$ 35,244	$ 663	$ 31,530

Share-based Compensation (Narra

Share-based Compensation (Narrative) (Details) - USD ($)	1 Months Ended		12 Months Ended
	Dec. 31, 2016	Oct. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
Maximum expected term of options (in years)			10 years
Stock-based compensation expense			$ 34,467,000	$ 31,471,000	$ 24,241,000
Purchase price of ESPP shares			9,098,000	6,724,000	4,105,000
Stock-based compensation capitalized to property and equipment			$ 5,295,000	$ 2,831,000	$ 1,126,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding	1,885,332		1,436,031	1,885,332	2,515,329	3,050,301
Company's closing stock price			$ 89.4
Unrecognized compensation costs			$ 3,800,000
Unrecognized compensation costs, period for recognition			1 year 37 days
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
Grants, other than options			651,936	598,390	401,158
Aggregate intrinsic value of awards vested			$ 36,000,000	$ 20,100,000
Fair value of awards vested in period			$ 20,400,000	$ 10,200,000
Grants in period, weighted average grant date fair value			$ 97.73	$ 78.39	$ 62.62
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
Stock-based compensation expense			$ 5,800,000	$ 8,300,000	$ 7,400,000
Grants, other than options			43,414	151,540	205,816
Aggregate intrinsic value of awards vested			$ 14,200,000	$ 21,800,000
Fair value of awards vested in period			$ 6,100,000	$ 7,000,000
Grants in period, weighted average grant date fair value			$ 94.66	$ 61.69	$ 47.18
Restricted Stock Units and Performance Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs			$ 72,100,000
Unrecognized compensation costs, period for recognition			2 years 168 days
Performance-vestingRSUs [Member] | Former CEO of Mortgage Returns [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants, other than options		29,006
Fair value of awards granted in period		$ 2,000,000
Incremental compensation cost	$ 200,000
2011 Equity Incentive Award Plan [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual automatic increase in common shares reserved for issuance, shares			1,666,666
Annual automatic increase in common shares reserved for issuance, as a percent of common stock outstanding			5.00%
2011 Equity Incentive Award Plan [Member] | Employee Stock Option [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance			2,666,666
2011 Equity Incentive Award Plan [Member] | Employee Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance			23,333,333
2011 Equity Incentive Award Plan [Member] | Performance Shares [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			0.00%
2011 Equity Incentive Award Plan [Member] | Performance Shares [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			200.00%
2009 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding			987,657
Executive Incentive Plan [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance			70,000,000
Maximum number of shares per participant per calendar year			1,000,000
Executive Incentive Plan [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares per participant per calendar year			1,000,000
Maximum grant date value allowable per participant per calendar year			$ 10,000,000
Employee Stock Purchase Plan [Member] | Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common stock, percent			85.00%
Grants in period, weighted average grant date fair value			$ 23.01	$ 24.11	$ 16.12
Number of shares purchased under ESPP			121,010	101,816	110,598
Purchase price of ESPP shares			$ 9,100,000	$ 6,700,000	$ 4,100,000
Unrecognized compensation cost related to employee stock purchase plan			$ 500,000
Expected recognized period under employee stock purchase plan			2 months

Share-based Compensation (Summa

Share-based Compensation (Summary of Company's Stock Option Activities) (Details) - Employee Stock Option [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of the period, Shares	1,885,332	2,515,329	3,050,301
Options granted Shares	6,601	14,506	385,776
Options exercised, Shares	(432,341)	(584,807)	(822,133)
Options forfeited or expired, Shares	(23,561)	(59,696)	(98,615)
Outstanding at end of the period, Shares	1,436,031	1,885,332	2,515,329
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning of the period, weighted average exercise price	$ 26.21	$ 24.40	$ 17.41
Options granted, weighted average exercise price	94.66	59.78	55.30
Options exercised, weighted average exercise price	23.61	18.08	12.28
Options forfeited or expired, weighted average exercise price	40.94	37.94	30.12
Outstanding at end of the period, weighted average exercise price	$ 27.06	$ 26.21	$ 24.40
Ending vested and expected to vest, Number of Shares at End of Period	1,431,645
Stock options exercisable at End of Period, Shares	1,250,119
Ending vested and expected to vest at December 31, 2012, Weighted Average Exercise Price	$ 26.98
Stock option exercisable at June 30, 2012, weighted average exercise price, Ending Balance	$ 24.05
Weighted average remaining contractual term at December 31, 2012	5 years 157 days
Ending vested and expected to vest, Weighted Average Remaining Contractual Term at December 31, 2012	5 years 153 days
Stock option exercisable, weighted average remaining Contractual term, Ending balance	5 years 66 days
Aggregate Intrinsic value at December 31, 2012	$ 89,554
Ending vested and expected to vest, Aggregate Intrinsic Value at December 31, 2012	89,393
Exercisable aggregate Intrinsic Value	$ 81,700

Share-based Compensation (Addit

Share-based Compensation (Additional Information Pertaining to Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stock options activity, additional information
Weighted average grant-date fair value per option granted	$ 45.44	$ 27.57	$ 26.13
Grant-date fair value of options vested	$ 4,994	$ 8,577	$ 8,285
Intrinsic value of options exercised	31,621	39,040	38,971
Proceeds received from options exercised	$ 10,208	$ 10,573	$ 10,094

Share-based Compensation (RSU a

Share-based Compensation (RSU and Performance Award Activity) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
RSUs [Member]
Summary of RSU activities
Outstanding at December 31, 2011	1,025,115	748,688	585,858
Granted	651,936	598,390	401,158
Released	(355,045)	(240,386)	(179,530)
Forfeited or expired	(142,548)	(81,577)	(58,798)
Outstanding at December 31, 2012	1,179,458	1,025,115	748,688
Ending vested and expected to vest at December 31, 2012	1,034,136
Weighted Average Grant Date Fair Value Outstanding at December 31, 2011	$ 64.47	$ 45.52	$ 27.20
Weighted Average Grant Date Fair Value Granted	97.73	78.39	62.62
Weighted Average Grant Date Fair Value Released	57.37	42.48	25.97
Weighted Average Grant Date Fair Value Forfeited	82.25	57.50	39.40
Weighted Average Grant Date Fair Value Outstanding at December 31, 2012	$ 82.84	$ 64.47	$ 45.52
Performance Shares [Member]
Summary of RSU activities
Outstanding at December 31, 2011	407,650	508,282	485,177
Granted	43,414	151,540	205,816
Released	(150,727)	(239,120)	(182,711)
Forfeited or expired	(5,873)	(13,052)	0
Outstanding at December 31, 2012	294,464	407,650	508,282
Ending vested and expected to vest at December 31, 2012	294,463
Weighted Average Grant Date Fair Value Outstanding at December 31, 2011	$ 46.77	$ 34.68	$ 25.61
Weighted Average Grant Date Fair Value Granted	94.66	61.69	47.18
Weighted Average Grant Date Fair Value Released	40.73	29.34	24.69
Weighted Average Grant Date Fair Value Forfeited	84.86	68.19	0
Weighted Average Grant Date Fair Value Outstanding at December 31, 2012	$ 56.17	$ 46.77	$ 34.68

Share-based Compensation (Valua

Share-based Compensation (Valuation Assumptions) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Stock Option [Member]
Schedule of Stock Options and Employee Stock Purchase Plan Valuation Assumptions
Risk-free interest rate	2.04%	1.38%
Expected Life of options (in years)	6 years 29 days	6 years 29 days
Expected dividend yield	0.00%	0.00%	0.00%
Volatility	48.00%	47.00%
Employee Stock Option [Member] | Minimum [Member]
Schedule of Stock Options and Employee Stock Purchase Plan Valuation Assumptions
Risk-free interest rate			1.50%
Expected Life of options (in years)			5 years
Volatility			48.00%
Employee Stock Option [Member] | Maximum [Member]
Schedule of Stock Options and Employee Stock Purchase Plan Valuation Assumptions
Risk-free interest rate			1.96%
Expected Life of options (in years)			6 years 29 days
Volatility			49.00%
Employee Stock Purchase Plan [Member]
Schedule of Stock Options and Employee Stock Purchase Plan Valuation Assumptions
Expected Life of options (in years)	179 days	183 days	6 months
Expected dividend yield	0.00%	0.00%	0.00%
Employee Stock Purchase Plan [Member] | Minimum [Member]
Schedule of Stock Options and Employee Stock Purchase Plan Valuation Assumptions
Risk-free interest rate	0.46%	0.46%	0.13%
Volatility	33.00%	33.00%	35.00%
Employee Stock Purchase Plan [Member] | Maximum [Member]
Schedule of Stock Options and Employee Stock Purchase Plan Valuation Assumptions
Risk-free interest rate	0.69%	0.48%	0.24%
Volatility	37.00%	49.00%	44.00%

Share-based Compensation (Stock

Share-based Compensation (Stock-Based Compensation Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stock-based compensation expense
Stock-based compensation expense	$ 34,467	$ 31,471	$ 24,241
Cost of revenues [Member]
Stock-based compensation expense
Stock-based compensation expense	6,786	4,835	3,218
Sales and marketing [Member]
Stock-based compensation expense
Stock-based compensation expense	5,223	4,429	2,752
Research and development [Member]
Stock-based compensation expense
Stock-based compensation expense	8,281	7,296	5,431
General and administrative [Member]
Stock-based compensation expense
Stock-based compensation expense	$ 14,177	$ 14,911	$ 12,840

Employee Benefit Plan (Details)

Employee Benefit Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Employee benefit plan, employer contribution percentage of employee contribution	50.00%	50.00%	50.00%
Employee benefit plan, maximum annual contribution per employee, percent of employees compensation	3.00%	3.00%	3.00%
Employee benefit plan, employer contribution amount	$ 3.9	$ 2.8	$ 2

Quarterly Results of Operatio69

Quarterly Results of Operations Data (Unaudited) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 112,886,000	$ 107,029,000	$ 104,125,000	$ 93,002,000	$ 96,181,000	$ 100,381,000	$ 90,098,000	$ 73,625,000	$ 417,042,000	$ 360,285,000	$ 253,937,000
Gross profit	64,614,000	67,426,000	65,858,000	58,234,000	63,338,000	68,163,000	61,645,000	46,994,000	256,132,000	240,140,000	169,729,000
Income before income taxes	3,417,000	18,984,000	17,987,000	5,006,000	14,766,000	21,272,000	16,846,000	3,722,000	45,394,000	56,606,000	34,477,000
Net income	$ 9,909,000	$ 14,519,000	$ 18,823,000	$ 9,599,000	$ 10,902,000	$ 13,780,000	$ 10,588,000	$ 2,506,000	$ 52,850,000	$ 37,776,000	$ 22,258,000
Basic (USD per share)	$ 0.29	$ 0.42	$ 0.55	$ 0.28	$ 0.33	$ 0.43	$ 0.36	$ 0.09	$ 1.55	$ 1.21	$ 0.76
Diluted (USD per share)	$ 0.28	$ 0.41	$ 0.52	$ 0.27	$ 0.31	$ 0.41	$ 0.34	$ 0.08	$ 1.48	$ 1.15	$ 0.72

SCHEDULE II VALUATION AND QUA70

SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Details) - Allowance for Doubtful Accounts [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 45	$ 124	$ 66
Charged (Credited) to Income	374	121	62
Deductions and Other	(79)	(200)	(4)	[1]
Balance at End of Period	$ 340	$ 45	$ 124
[1]	Accounts written off, net of recoveries.