Benefitfocus (BNFT) 10-K 27 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 24, 2015	Jun. 30, 2014
Document Information [Line Items]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	BNFT
Entity Registrant Name	Benefitfocus,Inc.
Entity Central Index Key	1576169
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		28,459,860
Entity Public Float			$318,751,978

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$51,074	$65,645
Marketable securities	5,135	13,168
Accounts receivable, net	21,311	23,668
Prepaid expenses and other current assets	4,242	4,322
Total current assets	81,762	106,803
Property and equipment, net	54,021	27,444
Intangible assets, net	951	1,256
Goodwill	1,634	1,634
Other non-current assets	1,650	2,474
Total assets	140,018	139,611
Current liabilities:
Accounts payable	5,589	4,354
Accrued expenses	9,171	3,911
Accrued compensation and benefits	17,374	14,183
Deferred revenue, current portion	20,384	15,158
Financing and capital lease obligations, current portion	4,197	4,288
Total current liabilities	56,715	41,894
Deferred revenue, net of current portion	74,126	65,063
Revolving line of credit	17,657	5,757
Financing and capital lease obligations, net of current portion	32,240	14,263
Other non-current liabilities	2,103	1,202
Total liabilities	182,841	128,179
Commitments and contingencies
Stockholders' (deficit) equity:
Preferred stock, par value $0.001, 5,000,000 shares authorized, no shares issued and outstanding at December 31, 2014 and 2013
Common stock, par value $0.001, 50,000,000 shares authorized, 25,608,937 and 24,495,651 shares issued and outstanding at December 31, 2014 and 2013, respectively	26	24
Additional paid-in capital	223,409	214,487
Accumulated deficit	-266,258	-203,079
Total stockholders' (deficit) equity	-42,823	11,432
Total liabilities and stockholders' (deficit) equity	$140,018	$139,611

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Preferred stock, par value	$0.00	$0.00
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	25,608,937	24,495,651
Common stock, shares outstanding	25,608,937	24,495,651

Consolidated_Statements_of_Ope

Consolidated Statements of Operations and Comprehensive Loss (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue	$137,420	$104,752	$81,739
Cost of revenue	87,470	62,411	44,400
Gross profit	49,950	42,341	37,339
Operating expenses:
Sales and marketing	48,467	36,072	27,905
Research and development	41,729	23,532	14,621
General and administrative	18,657	10,974	7,494
Change in fair value of contingent consideration		-43	121
Total operating expenses	108,853	70,535	50,141
Loss from operations	-58,903	-28,194	-12,802
Other income (expense):
Interest income	77	46	53
Interest expense on building lease financing obligations	-3,624	-1,768	-1,774
Interest expense on other borrowings	-682	-381	-202
Other expense	-22	-95	-64
Total other expense, net	-4,251	-2,198	-1,987
Loss before income taxes	-63,154	-30,392	-14,789
Income tax expense (benefit)	25	-31	84
Net loss	-63,179	-30,361	-14,873
Comprehensive loss	($63,179)	($30,361)	($14,873)
Net loss per common share:
Basic and diluted	($2.51)	($2.99)	($3.09)
Weighted-average common shares outstanding:
Basic and diluted	25,207,099	10,144,243	4,812,632

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Stockholders' (Deficit) Equity (USD $)	Total	Common Stock, No Par Value	Common Stock, $0.001 Par Value	Additional Paid-in Capital	Accumulated Deficit
In Thousands, except Share data
Balance at Dec. 31, 2011	($152,445)	$4,923			($157,368)
Balance (in shares) at Dec. 31, 2011		4,805,957
Exercise of stock options (in shares)		50,410
Exercise of stock options	108	108
Repurchase of common stock (in shares)		-64,020
Repurchase of common stock	-599	-122			-477
Stock-based compensation expense	712	712
Accretion of customer warrant	488	488
Net loss	-14,873				-14,873
Balance at Dec. 31, 2012	-166,609	6,109			-172,718
Balance (in shares) at Dec. 31, 2012		4,792,347
Exercise of stock options (in shares)		71,694	129,750
Exercise of stock options	699	168		531
Issuance of common stock (in shares)		5,000
Issuance of common stock	68	68
Effects of corporate restructuring (in shares)		-4,869,041	4,869,041
Effects of corporate restructuring		-7,328	5	7,323
Initial public offering, net of issuance costs (in shares)			3,000,000
Initial public offering, net of issuance costs	70,064		3	70,061
Conversion of redeemable convertible preferred stock (in shares)			16,496,860
Conversion of redeemable convertible preferred stock	135,477		16	135,461
Stock-based compensation expense	1,202	537		665
Accretion of customer warrant	892	446		446
Net loss	-30,361				-30,361
Balance at Dec. 31, 2013	11,432		24	214,487	-203,079
Balance (in shares) at Dec. 31, 2013			24,495,651
Exercise of stock options (in shares)	642,152		642,152
Exercise of stock options	2,818		1	2,817
Issuance of common stock upon vesting of restricted stock units, net of shares surrendered for taxes (in shares)		0	15,613
Issuance of common stock upon vesting of restricted stock units, net of shares surrendered for taxes	-226			-226
Issuance of common stock for cashless exercise of warrant (in shares)		0	455,521
Issuance of common stock for cashless exercise of warrant			1	-1
Conversion of redeemable convertible preferred stock (in shares)	16,496,860
Stock-based compensation expense	5,588			5,588
Accretion of customer warrant	744			744
Net loss	-63,179				-63,179
Balance at Dec. 31, 2014	($42,823)		$26	$223,409	($266,258)
Balance (in shares) at Dec. 31, 2014			25,608,937

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities
Net loss	($63,179)	($30,361)	($14,873)
Adjustments to reconcile net loss to net cash and cash equivalents (used in) provided by operating activities:
Depreciation and amortization	9,493	8,172	8,560
Stock-based compensation expense	5,588	1,202	712
Change in fair value and accretion of warrant	744	892	488
Interest accrual on financing obligation	3,624	1,768	1,774
Change in fair value of contingent consideration		-17	188
Provision for doubtful accounts		-32	98
Loss on disposal or impairment of property and equipment	25	65	17
Changes in operating assets and liabilities:
Accounts receivable, net	2,357	-10,264	-4,411
Accrued interest on short-term investments	162
Prepaid expenses and other current assets	833	-1,440	639
Other non-current assets	824
Accounts payable	-199	2,625	862
Accrued expenses	2,469	904	532
Accrued compensation and benefits	3,192	4,521	3,102
Contingent consideration related to acquisition			-320
Deferred revenue	14,288	22,701	14,747
Other non-current liabilities	901	331	293
Net cash and cash equivalents (used in) provided by operating activities	-18,878	1,067	12,408
Cash flows from investing activities
Purchases of short-term investments held to maturity	-12,959	-13,168
Proceeds from maturity of short-term investments held to maturity	20,830
Purchases of property and equipment	-9,824	-8,918	-6,308
Proceeds from sale of property and equipment		9
Net cash and cash equivalents used in investing activities	-1,953	-22,077	-6,308
Cash flows from financing activities
Proceeds from initial public offering, net of issuance costs		70,064
Draws on revolving line of credit	14,000	10,757
Payments on revolving line of credit	-2,100	-5,000
Proceeds from notes payable borrowing		1,465	4,535
Repayment of notes payable		-7,447	-1,074
Proceeds from exercises of stock options	2,817	699	108
Proceeds from issuance of common stock (excluding IPO)		68
Remittance of taxes upon vesting of restricted stock units	-226
Repurchases of common stock			-599
Payments of contingent consideration		-311	-2,078
Payments on financing and capital lease obligations	-8,231	-3,343	-3,145
Net cash and cash equivalents provided by (used in) financing activities	6,260	66,952	-2,253
Net (decrease) increase in cash and cash equivalents	-14,571	45,942	3,847
Cash and cash equivalents, beginning of year	65,645	19,703	15,856
Cash and cash equivalents, end of year	51,074	65,645	19,703
Supplemental disclosure of non-cash investing and financing activities
Property and equipment acquisitions in accounts payable and accrued expenses	4,226	524
Property and equipment acquired with financing and capital lease obligations	21,739	5,440	132
Post contract support acquired with financing obligations	754	3,872
Supplemental disclosure of cash flow information
Income taxes paid	38	169	40
Interest paid	$2,449	$2,146	$1,973

Organization_and_Description_o

Organization and Description of Business	12 Months Ended
	Dec. 31, 2014
Organization and Description of Business	1. Organization and Description of Business
	Benefitfocus, Inc. (the “Company”) is a leading provider of cloud-based benefits software solutions for consumers, employers, insurance carriers and brokers delivered under a software-as-a-service (“SaaS”) model. The financial statements of the Company include the financial position and operations of its wholly owned subsidiaries, Benefitfocus.com, Inc., Benefit Informatics, Inc. and BenefitStore, Inc.
	Corporate restructuring
	The Company, a Delaware corporation, was originally a wholly owned subsidiary of Benefitfocus.com, Inc., the South Carolina corporation that conducts the business of the Company. On March 13, 2013, the board of directors of each of Benefitfocus, Inc. and Benefitfocus.com, Inc. approved a corporate restructuring to be effected prior to the completion of the Company’s initial public offering (“IPO”) of shares of its common stock. On September 13, 2013, the Company restructured its organization by merging Benefitfocus.com, Inc. with a newly formed South Carolina corporation, which was a wholly owned subsidiary of the Company. As a result of the corporate restructuring, Benefitfocus.com, Inc. became a wholly owned operating subsidiary of the Company. Additionally, the common and preferred stockholders of Benefitfocus.com, Inc. became common and preferred stockholders, respectively, of Benefitfocus, Inc. and warrants that were exercisable for common shares of Benefitfocus.com, Inc. became exercisable for common shares of Benefitfocus, Inc. Similarly, holders of options to purchase common shares of Benefitfocus.com, Inc. became holders of options to purchase shares of common stock of Benefitfocus, Inc.
	Initial Public Offering
	In September 2013, the Company completed its IPO in which it issued and sold 3,000,000 shares of common stock and existing shareholders sold 2,675,250 shares of common stock at a public offering price of $26.50 per share. The Company did not receive any proceeds from the sale of common stock by the existing shareholders. The Company received net proceeds of $70,064 after deducting underwriting discounts and commissions of $5,565 and other offering expenses of $3,871. Upon the closing of the IPO, all shares of the Company’s then-outstanding redeemable convertible preferred stock automatically converted into 16,496,860 shares of its $0.001 par value common stock.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies
	Principles of Consolidation
	These consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. We are not the primary beneficiary of, nor do we have a controlling financial interest in, any variable interest entity. Accordingly, we have not consolidated any variable interest entity.
	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. Such estimates include revenue recognition and the customer relationship period, allowances for doubtful accounts and returns, valuations of deferred income taxes, long-lived assets, warrants, the useful lives of assets, capitalizable software development costs and the related amortization, contingent consideration, stock-based compensation, and the recognition and impairment assessment of acquired intangibles and goodwill. Determination of these transactions and account balances are based on the Company’s estimates and judgments. These estimates are based on the Company’s knowledge of current events and actions it may undertake in the future as well as on various other assumptions that it believes to be reasonable. Actual results could differ materially from these estimates.
	Revenue and Deferred Revenue
	The Company derives the majority of its revenue from software services fees, which consist primarily of monthly subscription fees paid by customers for access to and usage of the Company’s cloud-based benefits software solutions for a specified contract term. The Company also derives revenue from professional services which primarily include fees related to the integration of customers’ systems with the Company’s platform, which typically includes discovery, configuration, deployment, testing, and training.
	The Company recognizes revenue when there is persuasive evidence of an arrangement, the service has been provided, the fees to be paid by the customer are fixed and determinable and collectability is reasonably assured. The Company considers delivery of its cloud-based software services has commenced once it has granted the customer access to its platform.
	The Company’s arrangements generally contain multiple elements comprised of software services and professional services. The Company evaluates each element in an arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. The Company’s professional services are not sold separately from the software services and there is no alternative use for them. As such, the Company has determined that the professional services do not have standalone value. Accordingly, software services and professional services are combined and recognized as a single unit of accounting.
	The Company generally recognizes software services fees monthly based on the number of employees covered by the relevant benefits plans at contracted rates for a specified period of time, once the criteria for revenue recognition described above have been satisfied. The Company defers recognition of revenue for professional services fees and begins recognizing such revenue once the services are performed and the related software services have commenced, ratably over the longer of the contract term or the estimated expected life of the customer relationship. Costs incurred by the Company in connection with providing such professional services are charged to expense as incurred and are included in “Cost of revenue.”
	In January 2015, the Company adjusted the estimated expected life of its customer relationship. This change in estimate was the result of analyzing quantitative and qualitative observations in the market and the Company’s business. This change shortens the term over which deferred revenue will be recognized from 10 to 7 years and will be applied prospectively to unamortized professional services fees over the longer of the contract term or the adjusted estimated expected life of the customer relationship.
	Cost of Revenue
	Cost of revenue primarily consists of employee compensation, professional services, data center co-location costs, networking expenses, depreciation expense for computer equipment directly associated with generating revenue, amortization expense for capitalized software development costs, and infrastructure maintenance costs. In addition, the Company allocates a portion of overhead, such as rent, additional depreciation and amortization expense, and employee benefit costs, to cost of revenue based on headcount.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of bank checking accounts and money market accounts. The Company considers all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents.
	Marketable Securities
	Marketable securities consist of short-term investments in corporate securities. The Company classifies its marketable securities as held-to-maturity at the time of purchase. As a result, the marketable securities are recorded at amortized cost and any gains or losses realized upon maturity are reported in other expense, net in the consolidated statements of operations and comprehensive loss.
	Concentrations of Credit Risk
	The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash equivalents and accounts receivable. All of the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. The bank deposits of the Company might, at times, exceed federally insured limits and are generally uninsured and uncollateralized. The Company has not experienced any losses on cash and cash equivalents to date. To manage accounts receivable risk, the Company evaluates the creditworthiness of its customers and maintains an allowance for doubtful accounts.
	Accounts receivable were unsecured and were derived from revenue earned from customers located in the United States. Accounts receivable from one customer, Aetna, represented 13.3% and 11.3% of the total accounts receivable at December 31, 2014 and 2013, respectively.
	No customer represented more than 10% of total revenue for the years ended December 31, 2014 and 2013. Revenue from one customer, Aetna, represented 10.5% of total revenue for the year ended December 31, 2012. Revenue from this customer is reported in the Company’s Carrier segment.
	Accounts Receivable and Allowance for Doubtful Accounts and Returns
	Accounts receivable is stated at realizable value, net of allowances for doubtful accounts and returns. The Company utilizes the allowance method to provide for doubtful accounts based on management’s evaluation of the collectability of amounts due, and other relevant factors. Bad debt expense is recorded in general and administrative expense on the consolidated statements of operations and comprehensive loss. The Company’s estimate is based on historical collection experience and a review of the current status of accounts receivable. Historically, actual write-offs for uncollectible accounts have not significantly differed from the Company’s estimates. The Company removes recorded receivables and the associated allowances when they are deemed permanently uncollectible. However, higher than expected bad debts may result in future write-offs that are greater than the Company’s estimates. The allowance for doubtful accounts was $10 as of December 31, 2014 and 2013.
	The allowances for returns are accounted for as reductions of revenue and are estimated based on the Company’s periodic assessment of historical experience and trends. The Company considers factors such as the time lag since the initiation of revenue recognition, historical reasons for adjustments, new customer volume, complexity of billing arrangements, timing of software availability, and past due customer billings. The allowance for returns was $1,653 and $800 as of December 31, 2014 and 2013, respectively.
	Property and Equipment
	Property and equipment, including capitalized software development costs, are stated at cost less accumulated depreciation and amortization. Expenditures for major additions and improvements are capitalized. Depreciation and amortization is recognized over the estimated useful lives of the related assets using the straight-line method.
	The estimated useful lives for significant property and equipment categories are generally as follows:
	Computers and related equipment	3-7 years
	Furniture and fixtures	7 years
	Other equipment	5-12 years
	Purchased software and licenses	1-7 years
	Vehicles	5 years
	Buildings	30 years
	Leasehold improvements	Lesser of estimated useful life of asset or lease term
	Useful lives of significant assets are periodically reviewed and adjusted prospectively to reflect the Company’s current estimates of the respective assets’ expected utility. Costs associated with maintenance and repairs are expensed as incurred.
	In the event the Company has been deemed the owner for accounting purposes of construction projects in build-to-suit lease arrangements, the estimated construction costs incurred to date are recorded as assets in Property and Equipment, net. Upon occupancy of facilities under build-to-suit leases, the Company assesses whether arrangements qualify for sales recognition under the sale-leaseback accounting guidance. If the Company continues to be the deemed owner for accounting purposes, the cost of the building is depreciated over its estimated useful life.
	Capitalized Software Development Costs
	The Company capitalizes certain costs related to its software developed or obtained for internal use. Costs related to preliminary project activities and post-implementation activities are expensed as incurred. Internal and external costs incurred during the application development stage, including upgrades and enhancements representing modifications that will result in significant additional functionality, are capitalized. Software maintenance and training costs are expensed as incurred. Capitalized costs are recorded as part of property and equipment and are amortized on a straight-line basis over the software’s estimated useful life which is three years. The Company evaluates these assets for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets.
	Identifiable Intangible Assets
	Identifiable intangible assets with finite lives are recorded at their fair values at the date of acquisition and are amortized on a straight-line basis over their respective estimated useful lives, which is the period over which the asset is expected to contribute directly or indirectly to future cash flows. The estimated remaining useful lives used in computing amortization range from 1 to 4 years.
	Impairment of Long-Lived Assets and Goodwill
	The Company reviews long-lived assets and definite-lived intangible assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Recoverability of the long-lived asset is measured by a comparison of the carrying amount of the asset or asset group to future undiscounted net cash flows expected to be generated. If such assets are not recoverable, the impairment to be recognized, if any, is measured as the amount by which the carrying amount of the assets exceeds the estimated fair value (discounted cash flow) of the assets or asset group. Assets held for sale are reported at the lower of the carrying amount or fair value, less costs to sell.
	Goodwill represents the excess of the aggregate of the fair value of consideration transferred in a business combination over the fair value of assets acquired, net of liabilities assumed. Goodwill is not amortized; rather, goodwill is tested for impairment at the reporting unit level as of October 31 of each year, or more frequently if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value.
	The Company performs a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying value before performing a two-step approach to testing goodwill for impairment for each reporting unit. The reporting units are determined by the components of the Company’s operating segments that constitute a business for which both (1) discrete financial information is available and (2) segment management regularly reviews the operating results of that component. If it is more likely than not that the fair value of a reporting unit is less than its carrying value, the Company performs the impairment test by applying a fair-value-based test. The first step measures for impairment by applying fair-value-based tests at the reporting unit level. The second step (if necessary) measures the amount of impairment by applying fair-value-based tests to the individual assets and liabilities within each reporting unit.
	As part of determining its reporting units, the Company has identified two operating segments, Employer and Carrier. To determine the fair value of the Company’s reporting units, the Company has used a discounted cash flow analysis, which requires significant assumptions and estimates about future operations. Significant judgments inherent in this analysis include the determination of an appropriate discount rate, estimated terminal value and the amount and timing of expected future cash flows. The Company may also determine fair value of its reporting units using a market approach by applying multiples of earnings of peer companies to its operating results.
	Financing Obligations
	In its build-to-suit lease arrangements where the Company is involved in the construction of its buildings, the Company is deemed the owner for accounting purposes during the construction period. The Company records an asset for the amount of the total project costs in Property and Equipment, net and the related financing obligation in Financing and Capital Lease Obligations on the Consolidated Balance Sheet. Once construction is complete, the Company determines if the asset qualifies for sale-leaseback accounting treatment. If the arrangement does not qualify for sale-lease back treatment, the Company continues to reduce the obligation over the lease term as payments are made and depreciates the asset over its useful life. The Company does not report rent expense for the portion of the rent payment determined to be related to the assets which are owned for accounting purposes. Rather, this portion of the rent payment under the lease is recognized as a reduction of the financing obligation and as interest expense.
	Financing obligations also include liabilities for service agreements related to property and equipment under capital leases.
	Sales Commissions
	Sales commissions are expensed when the sales contract is executed by the customer.
	Advertising
	The Company expenses advertising costs as they are incurred. Direct advertising costs for 2014, 2013, and 2012 were $394, $265, and $257, respectively.
	Comprehensive Loss
	The Company’s net loss equals comprehensive loss for all periods presented.
	Stock-Based Employee Compensation
	Stock-based employee compensation is measured based on the grant-date fair value of the awards and recognized in the Consolidated Statements of Operations and Comprehensive Loss over the period during which the award holder is required to perform services in exchange for the award, which is the vesting period. Compensation expense is recognized over the vesting period of the applicable award using the straight-line method. Compensation costs related to restricted stock units (‘RSUs’) is recorded based on the market price on the grant date. The Company uses the Black-Scholes option pricing model for estimating the fair value of stock options. The use of the option valuation model requires the input of subjective assumptions, including the estimated fair value of the Company’s common stock in the periods preceding the IPO, the expected life of the option and the expected stock price volatility based on peer companies. Additionally, the recognition of stock-based compensation expense requires the estimation of the number of options that will ultimately vest and the number of options that will ultimately be forfeited.
	Income Taxes
	The Company uses the asset and liability method for income tax accounting. This method requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax basis of assets and liabilities, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled. Valuation allowances are recorded to reduce deferred tax assets to the amount the Company believes is more likely than not to be realized. The tax benefits of uncertain tax positions are recognized only when the Company believes it is more likely than not that the tax position will be upheld on examination by the taxing authorities based on the merits of the position. The Company recognizes interest and penalties, if any, related to unrecognized income tax benefits in income tax expense.
	Basic and Diluted Net Loss per Common Share
	The Company uses the two-class method to compute net loss per common share because the Company has issued securities, other than common stock, that contractually entitle the holders to participate in dividends and earnings of the Company. The two-class method requires earnings for the period to be allocated between common stock and participating securities based upon their respective rights to receive distributed and undistributed earnings. Holders of each series of the Company’s redeemable convertible preferred stock are entitled to participate in distributions, when and if declared by the board of directors that are made to common stockholders, and as a result are considered participating securities.
	Under the two-class method, for periods with net income, basic net income per common share is computed by dividing the net income attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Net income attributable to common stockholders is computed by subtracting from net income the portion of current year earnings that the participating securities would have been entitled to receive pursuant to their dividend rights had all of the year’s earnings been distributed. No such adjustment to earnings is made during periods with a net loss, as the holders of the participating securities have no obligation to fund losses. Diluted net loss per common share is computed under the two-class method by using the weighted-average number of shares of common stock outstanding plus, for periods with net income attributable to common stockholders, the potential dilutive effects of stock awards and warrants. In addition, the Company analyzes the potential dilutive effect of the outstanding participating securities under the “if-converted” method when calculating diluted earnings per share, in which it is assumed that the outstanding participating securities convert into common stock at the beginning of the period. The Company reports the more dilutive of the approaches (two-class or “if-converted”) as its diluted net income per share during the period. Due to net losses for the years ended December 31, 2014, 2013, and 2012 basic and diluted loss per share were the same, as the effect of potentially dilutive securities would have been anti-dilutive.
	Recent Accounting Pronouncements
	In May 2014, the FASB issued ASU No. 2014-09 “Revenue from Contracts with Customers”, which amends the revenue recognition requirements in the FASB Accounting Standards Codification (ASC). This statement requires that an entity recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The statement shall be applied using one of two methods: retrospectively to each prior reporting period presented, or retrospectively with the cumulative effect of initially applying this statement recognized at the date of initial application. The Company has not yet determined which method it will apply. This statement is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. The Company is currently evaluating the impact of this guidance on the Company’s consolidated financial position and results of operations.

Net_Loss_Per_Common_Share

Net Loss Per Common Share	12 Months Ended
	Dec. 31, 2014
Net Loss Per Common Share	3. Net Loss Per Common Share
	Diluted loss per common share is the same as basic loss per common share for all periods presented because the effects of potentially dilutive items were anti-dilutive given the Company’s net loss. The following common share equivalent securities have been excluded from the calculation of weighted-average common shares outstanding because the effect is anti-dilutive for the periods presented:
		Year Ended December 31,
	Anti-Dilutive Common Share Equivalents	2014			2013			2012
	Redeemable convertible preferred stock:
	Series A		—			—			14,055,851
	Series B		—			—			2,441,009
	Restricted stock units		720,370			97,700			—
	Stock options		2,382,881			3,058,795			3,121,064
	Warrant to purchase common stock		—			500,000			500,000
	Total anti-dilutive common share equivalents		3,103,251			3,656,495			20,117,924
	Basic and diluted net loss per common share is calculated as follows:
		Year Ended December 31,
		2014			2013			2012
	Numerator:
	Net loss	$	(63,179	)	$	(30,361	)	$	(14,873	)
	Net loss attributable to common stockholders	$	(63,179	)	$	(30,361	)	$	(14,873	)
	Denominator:
	Weighted-average common shares outstanding, basic and diluted		25,207,099			10,144,243			4,812,632
	Net loss per common share, basic and diluted	$	(2.51	)	$	(2.99	)	$	(3.09	)

Marketable_Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2014
Marketable Securities	4. Marketable Securities
	Marketable securities consist of corporate bonds and are classified as held-to-maturity. The amortized cost basis and net carrying amount of marketable securities was $5,135 and $13,168 and the aggregate fair value, determined by Level 2 inputs, was $5,134 and $13,166, as of December 31, 2014 and 2013, respectively. The gross unrealized holding gains were $0 and $0 and the gross unrealized losses were $1 and $2, as of December 31, 2014 and 2013, respectively. Corporate bonds held in marketable securities have contractual maturities of between 1 and 3 months as of December 31, 2014.
	The following table presents information about the Company’s investments that were in an unrealized loss position and for which an other-than-temporary impairment has not been recognized in earnings as of December 31:
			2014			2013
	Aggregate fair value of investments with unrealized losses (1)		$	5,135		$	1,281
	Aggregate amount of unrealized losses			(1	)		(2	)
	-1	Investments have been in a continuous loss position for less than 12 months

Fair_Value_Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2014
Fair Value Measurement	5. Fair Value Measurement
	The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, net accounts receivable, accounts payable and other accrued liabilities, and accrued compensation and benefits, approximate fair value due to their short-term nature. The carrying value of the Company’s financing obligations and revolving line of credit approximates fair value, considering the borrowing rates currently available to the Company for financing obligations with similar terms and credit risks.
	The Company uses a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis, as well as assets and liabilities measured at fair value on a non-recurring basis, in periods subsequent to their initial measurement. The hierarchy requires the Company to use observable inputs when available, and to minimize the use of unobservable inputs when determining fair value. The three tiers are defined as follows:
	Level 1. Quoted prices (unadjusted) in active markets for identical assets or liabilities.
	Level 2. Other inputs that are directly or indirectly observable in the marketplace.
	Level 3. Unobservable inputs for which there is little or no market data, which require the Company to develop its own assumptions.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	The Company evaluates its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level to classify them for each reporting period. This determination requires significant judgments to be made.
	The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis using the above categories, as of December 31, 2014 and 2013.
			December 31, 2014
	Description		Level 1			Level 2		Level 3		Total
	Cash Equivalents:
	Money market mutual funds (1)		$	50,695		$	—	$	—	$	50,695
	Total assets		$	50,695		$	—	$	—	$	50,695
			December 31, 2013
	Description		Level 1			Level 2		Level 3		Total
	Cash Equivalents:
	Money market mutual funds (1)		$	65,443		$	—	$	—	$	65,443
	Total assets		$	65,443		$	—	$	—	$	65,443
	-1	Money market funds are classified as cash equivalents in the Company’s consolidated balance sheets. As short-term, highly liquid investments readily convertible to known amounts of cash, with remaining maturities of three months or less at the time of purchase, the Company’s cash equivalent money market funds have carrying values that approximate fair value.
	Assets Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
	The following table presents the changes in the Company’s Level 3 instruments measured at fair value on a recurring basis for the year ended December 31, 2013 (no such assets in 2014):
			2013
	Balance of contingent consideration at beginning of period		$	328
	Change in fair value			(43	)
	Accretion of discount			26
	Payment			(311	)
	Balance of contingent consideration at end of period		$	—

Property_and_Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2014
Property and Equipment	6. Property and Equipment
	Property and equipment consists of the following as of December 31:
		2014			2013
	Building, leased	$	7,965		$	7,965
	Computers and related equipment		18,871			13,954
	Purchased software and licenses		20,392			17,556
	Software developed		18,397			16,182
	Furniture and fixtures		3,834			2,717
	Leasehold improvements		3,334			1,730
	Other equipment		2,009			1,922
	Vehicles		111			111
	Construction in progress		24,296			1,781
	Total property and equipment, at cost		99,209			63,918
	Accumulated depreciation and amortization		(45,188	)		(36,474	)
	Property and equipment, net	$	54,021		$	27,444
	Depreciation and amortization expense on property and equipment was $9,188, $7,849 and $8,225, for the years ended December 31, 2014, 2013 and 2012, respectively. Property and equipment at December 31, 2014 and 2013 includes fixed assets acquired under capital lease agreements of $8,569 and $8,463, respectively. Accumulated depreciation of assets under capital leases totaled $1,521 and $2,033 as of December 31, 2014 and 2013, respectively. Amortization of assets under capital leases is included in depreciation expense.
	During 2012, the Company determined it was no longer probable that certain software developed for internal use and certain purchased software would produce expected cash flows for the remainder of their respective useful lives. As a result, the Company recognized an impairment charge related to these long-lived assets totaling $1,051 in the Employer segment, for the year ended December 31, 2012.
	The Company capitalized software development costs of $2,215 and $2,751 for the years ended December 31, 2014 and 2013, respectively. Amortization of capitalized software development costs totaled $2,257, $2,618 and $3,145 during the years ended December 31, 2014, 2013 and 2012, respectively. The net book value of capitalized software development costs was $4,134 and $4,101 at December 31, 2014, and 2013, respectively.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets	7. Goodwill and Intangible Assets
	The Company’s goodwill balance of $1,634 is solely attributable to the Employer reporting unit. There have been no changes in the carrying amount of goodwill in the years ended December 31, 2014 and 2013.
	Information regarding the Company’s acquisition-related intangible assets is as follows:
		As of December 31, 2014
		Gross		Accumulated			Net Carrying		Weighted-
		Carrying		Amortization			Amount		Average
		Amount							Remaining
									Useful Life
									(in years)
	Trademarks	$	240	$	(212	)	$	28		0.6
	Customer agreements		2,060		(1,137	)		923		3.6
	Non-compete agreements		126		(126	)		—		—
	Total	$	2,426	$	(1,475	)	$	951		3.5
		As of December 31, 2013
		Gross		Accumulated			Net Carrying		Weighted-
		Carrying		Amortization			Amount		Average
		Amount							Remaining
									Useful Life
									(in years)
	Trademarks	$	240	$	(164	)	$	76		1.6
	Customer agreements		2,060		(880	)		1,180		4.6
	Non-compete agreements		126		(126	)		—		—
	Total	$	2,426	$	(1,170	)	$	1,256		4.4
	Amortization expense of acquisition-related intangible assets for the years ended December 31, 2014, 2013 and 2012 was $305, $323 and $335, respectively. As of December 31, 2014, expected amortization expense for the intangible assets for each of the next five years and thereafter was as follows:
	2015	$	286
	2016		257
	2017		257
	2018		151
	2019		—
	Total	$	951
	There were no impairments of intangible assets during the years ended December 31, 2014, 2013 and 2012.

Revolving_Line_of_Credit_and_N

Revolving Line of Credit and Notes Payable	12 Months Ended
	Dec. 31, 2014
Revolving Line of Credit and Notes Payable	8. Revolving Line of Credit and Notes Payable
	During 2013, the Company transitioned its general business financing from its existing master credit facility to a revolving line of credit at a different bank.
	At January 1, 2013, the Company had a $6,000 master credit facility under which two senior secured promissory notes totaling $4,535 were outstanding (“Credit Facility Notes”). In March 2013 and June 2013, the Company borrowed an additional $874 and $591, respectively, under two additional senior secured promissory notes bearing interest at fixed annual rates ranging from 3.6% to 3.7% and repayable in equal monthly installments of principal and interest through dates ranging from December 2015 to July 2016.
	On August 27, 2013, the Company entered into a loan and security agreement with Silicon Valley Bank for a revolving line of credit of up to $35,000 for working capital, to fund general business requirements, and to repay the indebtedness under the master credit facility and other senior secured promissory notes.
	In August 2014, the borrowing limit under the Company’s line of credit increased from $15,000 to $35,000 in accordance with the terms of the agreement as amended on December 10, 2013. Borrowing capacity under the line of credit is subject to a borrowing base limit that is a function of the Company’s monthly recurring revenue as adjusted to reflect lost customer revenue during the previous quarter. Therefore, credit available under the line of credit may be less than the specified limit.
	Advances can be designated as LIBOR advances or prime rate advances. LIBOR advances bear interest at 2.75% plus the greater of 0.50% or current LIBOR for the applicable period, generally 30 days, adjusted for certain regulatory reserve requirements. The LIBOR rate is adjusted approximately monthly. Prime Rate advances bear interest at the prime rate as published in the Wall Street Journal. The line of credit has an annual commitment fee of $70 and an unused line of credit fee of a rate of 0.20% per year.
	The Company made customary affirmative and negative covenants in connection with the loan and security agreement, including financial covenants related to liquidity and revenue growth. In the event of a default, Silicon Valley Bank may declare all obligations immediately due and stop advancing money or extending credit under the line of credit. The line of credit is collateralized by substantially all of the Company’s tangible and intangible assets, including any proceeds of intellectual property (but not the underlying intellectual property itself), and the Company has agreed not to encumber any of its intellectual property without Silicon Valley Bank’s prior written consent. As of December 31, 2014, the Company was in compliance with the covenants.
	On August 30, 2013, the Company borrowed $5,757 under this line of credit, which it used to repay all of the amounts outstanding under its master credit facility and two senior promissory notes with its previous lender. In September 2013, the Company borrowed and repaid an additional $5,000 under this line of credit.
	In June 2014, the Company borrowed $7,000 under its line of credit, which was used to fund the general operations of the Company. In December 2014, the Company borrowed an additional $7,000 to fund the general operations of the Company and repaid $2,100 under its line of credit.
	As of December 31, 2014, the amount outstanding under this line of credit was $17,657 and the amount available to borrow was $12,507. The amount outstanding, which represents principal and currently bears interest at 3.25%, is due August 27, 2016. No other amounts are due in any other year.

Commitment_and_Contingencies

Commitment and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitment and Contingencies	9. Commitment and Contingencies
	Operating Lease Commitments
	In September 2014, the Company entered into an amendment to its operating lease for office space in Greenville, South Carolina. The amendment expands the space leased, extends the term of the lease for five years to February 2020, and grants the Company the right to extend the lease for five additional one-year periods. The amended lease contains a free-rent period and a provision for escalating rent payments. Accordingly, rent expense will be recognized on a straight-line basis over the lease term. Monthly lease payments under the amended lease will begin February 2015. Expenses under this lease will total approximately $95 per quarter.
	In February 2013, the Company entered into an amendment to a 2009 operating lease for additional office space. The lease commenced January 1, 2014 and will terminate in 2024 as stated in the original agreement.
	In August 2013, the Company entered into an amendment to a 2012 office lease agreement for its facility in Tulsa, Oklahoma. Under the terms of the lease agreement, the Company has committed to extend its lease term to April 2015.
	The Company also leases office facilities under various non-cancelable operating lease agreements with original lease periods expiring between 2017 and 2029. Some of the leases provide for renewal terms at the Company’s option. Certain future minimum lease payments due under these operating lease agreements contain free rent periods or escalating rent payment provisions. These leases generally do not contain purchase options. Rent expense on these operating leases is recognized over the term of the lease on a straight-line basis.
	Rent expense totaled $4,099, $2,517 and $1,946 for the years ended December 31, 2014, 2013 and 2012, respectively.
	Future minimum lease payments are as follows:
		Operating
		Leases
	Year Ending December 31,
	2015	$	3,857
	2016		3,912
	2017		3,934
	2018		3,747
	2019		3,841
	Thereafter		20,110
	Total minimum lease payments	$	39,401
	Financing and Capital Lease Obligations
	The Company has entered into various capital lease arrangements to obtain property and equipment for operations. These agreements range from 12 months to 5 years with interest rates ranging from 3.0% to 12.4%. The leases are secured by the underlying leased property and equipment.
	In September 2014, the Company entered into an agreement for support services for call hosting. The Company recorded this agreement as a financing obligation. Total payments under this one-year agreement total $150. As of December 31, 2014, financing obligations include $113 under this agreement.
	In April 2014, the Company entered into a lease with a 3-year term for data processing equipment and software. The total payments under the lease are $3,779, including a down payment of $1,340 and aggregate monthly payments of $2,439. The lease provides for a bargain purchase option at the end of its 3 year term. As of December 31, 2014, capital lease obligations include amounts under this lease of $1,803.
	Related to the April 2014 capital lease, the Company recorded a financing obligation for support services for data processing equipment. Total payments under this three-year arrangement are $629, including a down payment of $223 and aggregate monthly payments of $406. As of December 31, 2014, financing obligations include $300 under this agreement.
	In November 2013, the Company entered into a lease with a term of 3 years to finance data processing equipment and software. The total payments under the lease are $4,160. The present value of the lease payments exceeds the fair value of assets leased at inception. The Company accounts for this arrangement as a capital lease. As of December 31, 2014 and 2013, capital lease obligations include amounts under this lease of $2,355 and $3,988, respectively.
	Related to the November 2013 capital lease, the Company entered into a 3 year financing obligation for support services of data and processing equipment. The total payments under the arrangement are $4,039. The Company accounts for this arrangement as a financing obligation. As of December 31, 2014 and 2013, financing obligations include $2,287 and $3,872, respectively, under this agreement.
	In March 2013, the Company entered into a lease with a term of 3 years to finance data processing equipment and software. The total payments under the lease are $1,117. The lease provides for a bargain purchase option at the end of its term. The Company accounts for this arrangement as a capital lease. As of December 31, 2014 and 2013, capital lease obligations include amounts under this lease of $448 and $785, respectively.
	The Company entered into additional various leases with terms ranging from one year or less to five years to finance data processing equipment and software. The leases contain terms that either provide for the title to pass to the Company at the end of its term, or the lease term exceeds 75% of economic life of the asset, or the present value of the minimum lease payments exceeds 90% of the fair value of assets leased. The Company accounts for these arrangements as capital leases. As of December 31, 2014 and 2013, capital lease obligations include amounts under these leases of $135 and $216, respectively.
	In 2011, the Company entered into a lease with a term of 3 years to finance data processing equipment. The lease provides for a bargain purchase option at the end of the term. The total payments under the lease are $3,005. The Company accounts for this arrangement as a capital lease. As of December 31, 2014 and 2013, capital lease obligations include amounts under this lease of $0 and $465, respectively.
	Financing obligations were $31,697 and $13,097, as of December 31, 2014 and 2013, respectively, and consist of obligations for build-to-suit lease arrangements and the support components of a software financing arrangement. The aggregate amount of future minimum payments for financing obligations was $89,901 at December 31, 2014 which includes aggregate payments of $14,357 related to the headquarters building build-to-suit arrangement and $72,754 related to assets under construction under a build-to-suit lease entered into in December 2013. Details of the build-to-suit lease arrangements are disclosed in Note 15 “Related Parties.” Financing Obligations are allocated as follows:
		As of December 31,
		2014			2013
	Headquarters building, build-to-suit	$	8,873		$	9,023
	Software support		2,700			3,872
	Construction in progress, build-to-suit		20,124			202
	Total financing obligations	$	31,697		$	13,097
	Less: current portion		(1,720	)		(1,702	)
	Financing obligations, net of current portion	$	29,977		$	11,395
	Future minimum lease payments are as follows:
		Capital			Financing
		Leases			Obligations
	Year Ending December 31,
	2015	$	2,621		$	7,462
	2016		1,998			7,185
	2017		323			6,265
	2018		2			6,407
	2019		—			6,599
	Thereafter		—			55,983
	Total minimum lease and financing obligation payments		4,944		$	89,901
	Less: imputed interest		(204	)
	Less: current portion		(2,477	)
	Capital lease obligations, net of current portion	$	2,263
	Contractual Commitments
	In December 2013, the Company entered into a 15 year lease for additional office space at its Charleston, South Carolina campus. Under the build-to-suit arrangement, the leased premises will be constructed by and leased from an entity with which two of the Company’s significant stockholders and executives are affiliated. The lease payments will commence in January 2015. The total minimum payments under the arrangement are $81,487 based on an estimated rentable area of approximately 145,000 square feet. In connection with the lease, the Company entered into an option to lease space in two additional adjacent buildings. The option term is 36 months and requires the Company to incur costs annually prior to the exercise of the option in the amount of up to $466 per year. If the Company terminates the option or does not exercise the option prior to expiration it will incur termination fees pro-rated through the dates of termination or expiration. The maximum liability for termination fees is $757. The commitment for the lease and pro-rated termination fees is not accrued in the consolidated balance sheet of the Company. Had the Company terminated the options effective December 31, 2014, the liability for the termination fee would have been $265. The pro-rated commitment for the annual option expense is accrued in other non-current liabilities in the balance sheet. The minimum lease payments related to this lease have been excluded from the future minimum lease payment schedule above.
	The Company also has $5,001 of non-cancellable contractual commitments as of December 31, 2014 related to the purchase of software and colocation services. These commitments are not accrued in the consolidated balance sheet of the Company.
	Legal Contingencies
	The Company may become a party to a variety of legal proceedings that arise in the normal course of business. While the results of such normal course legal proceedings cannot be predicted with certainty, management believes, based on current knowledge, that the final outcome of any matters will not have a material adverse effect on the Company’s business, financial position, results of operations or cash flows.

StockBased_Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2014
Stock-Based Compensation	10. Stock-Based Compensation
	Employee Stock-based Compensation Plan
	The Company maintains the Amended and Restated Benefitfocus.com, Inc. 2000 Stock Option Plan (the “2000 Plan”) and the Benefitfocus.com, Inc. 2012 Stock Plan, as amended (the “2012 Plan”), pursuant to which the Company has reserved 5,069,853 shares of its common stock for issuance to its employees, directors and non-employee third parties. The 2012 Plan, effective on January 31, 2012, serves as the successor to the 2000 Plan and permits the granting of incentive stock options, non-statutory stock options, stock bonuses, stock purchase rights, stock appreciation rights, and restricted stock units and awards. No new awards will be issued under the 2000 Plan as of the effective date of the 2012 Plan. Outstanding awards under the 2000 Plan continue to be subject to the terms and conditions of the 2000 Plan. Shares available for grant under the 2000 Plan, which were reserved but not issued or subject to outstanding awards under the 2000 Plan as of the effective date, were added to the reserves of the 2012 Plan. As of December 31, 2014, the Company had 1,966,602 shares allocated to the 2012 Plan, but not yet issued.
	The terms of the stock-based award grants, including the exercise price per share and vesting periods, are determined by the Chairman of the Board who is delegated the authority by the Company’s board of directors. Stock options are granted at exercise prices not less than the estimated fair market value of the Company’s common stock at the date of grant. The grant date value of restricted stock units is equal to the closing price of the Company’s stock on the date of grant, or, if not a trading day, the closing price of the previous trading day. Generally, the Company issues previously unissued shares for the exercise of stock options or exchange of restricted stock units; however, previously acquired shares may be reissued to satisfy future issuances. The options and restricted stock unit awards typically vest quarterly over a four-year period. The options expire 10 years from the grant date. Compensation expense for the fair value of the stock-based awards at their grant date is recognized ratably over the vesting schedule.
	The Company has issued two types of awards under these plans: options and restricted stock units. The following table sets forth the number of awards outstanding for each award type is as follows:
		Outstanding at December 31,
	Award type	2014			2013		2012
	Stock options		2,382,881			3,058,795		3,121,064
	Restricted stock units		720,370			97,700		—
	Stock-based compensation expense related to stock-based awards is included in the following line items in the accompanying consolidated statements of operations and comprehensive loss for the years ended December 31:
		2014			2013		2012
	Cost of revenue	$	986		$	274	$	195
	Sales and marketing		1,395			171		68
	Research and development		1,376			255		130
	General and administrative		1,831			502		319
		$	5,588		$	1,202	$	712
	The total compensation cost related to non-vested awards not yet recognized as of December 31, 2014 was $23,767 and will be recognized over a weighted-average period of approximately 3.4 years.
	Restricted Stock Units
	During 2014, the Company granted restricted stock units under the 2012 Plan. Restricted stock units granted to employees vest in equal annual installments generally over 4 years from the grant date. The fair value of the stock at the time of grant is amortized based on a straight-line basis over the period of vesting. Income tax benefits resulting from vesting of restricted stock are recognized in the period the unit is exchanged to the extent the expense has been recognized.
	The summary of unvested restricted stock units is as follows:
		Restricted			Weighted
		stock units			average
					grant date
					fair value
	Unvested at December 31, 2013		97,700		$	48.31
	Granted		679,587			37.97
	Forfeited		(33,175	)		46.87
	Vested		(23,742	)		48.23
	Unvested at December 31, 2014		720,370		$	38.63
	As of December 31, 2014, the number and intrinsic value of restricted stock units expected to vest was 662,186 and $21,746, respectively. The aggregate fair value of restricted stock units vested during the year ended December 31, 2014 was $661. No restricted stock units vested during 2013 or 2012.
	Stock options
	The following is a summary of the option activity for the year ended December 31, 2014:
		Number of			Weighted-		Weighted-		Aggregate
		Options			Average		Average		Intrinsic Value
					Exercise		Remaining
					Price		Contractual
							Term
							(in years)
	Outstanding balance at December 31, 2013		3,058,795		$	6.75
	Granted		—			—
	Exercised		(642,152	)		4.39
	Forfeited		(31,664	)		9.98
	Expired		(2,098	)		1.38
	Outstanding balance at December 31, 2014		2,382,881		$	7.39		4	$	60,652
	Exercisable at December 31, 2014		2,064,624		$	6.84		3.4	$	53,690
	Vested and expected to vest at December 31, 2014		2,374,256		$	7.37		4	$	60,465
	The aggregate intrinsic value of employee options exercised during the years ended December 31, 2014, 2013, and 2012 was $23,397, $6,448 and $293, respectively.
	The Company values stock options using the Black-Scholes option-pricing model, which requires the input of subjective assumptions, including the per share fair value as a private company, risk-free interest rate, expected life, expected stock price volatility and dividend yield. Prior to the IPO, the Company was a private company with no active public market for its common stock. The Company has periodically determined for financial reporting purposes the estimated per share fair value of its common stock at various dates using contemporaneous valuations performed in accordance with the guidance outlined in the American Institute of Certified Public Accountants Practice Aid, “Valuation of Privately Held Company Equity Securities Issued as Compensation.” When determining the fair market value of its common stock, the Company considered what it believes to be comparable publicly traded companies, discounted free cash flows, and an analysis of its enterprise value. The risk-free interest rate assumption is based upon observed interest rates for constant maturity U.S. Treasury securities consistent with the expected term of the Company’s employee stock options. The expected life represents the period of time the stock options are expected to be outstanding and is based on the simplified method. Under the simplified method, the expected life of an option is presumed to be the mid-point between the vesting date and the end of the contractual term. The Company used the simplified method due to the lack of sufficient historical exercise data to provide a reasonable basis upon which to otherwise estimate the expected life of the stock options. The Company has a limited history of trading as a public company, therefore expected volatility was based on historical volatilities for publicly traded stock of comparable companies over the estimated expected life of the stock options. The Company assumed no dividend yield because it does not expect to pay dividends in the near future, which is consistent with the Company’s history of not paying dividends.
	The following table summarizes the assumptions used for estimating the fair value of stock options granted for the years ended December 31, (No options granted in 2014):
		2013			2012
	Risk-free interest rate		1.0% - 1.7%			0.8% - 1.2%
	Expected term (years)		6.08			6.08
	Expected volatility		52%			53% - 55%
	Expected dividend yield		0%			0%
	Weighted-average grant date fair value per share	$	7.71		$	4.24

Stockholders_Deficit

Stockholders' Deficit	12 Months Ended
	Dec. 31, 2014
Stockholders' Deficit	11. Stockholders’ Deficit
	Preferred stock
	Upon the closing of the IPO, all shares of the Company’s then-outstanding redeemable convertible preferred stock automatically converted into 16,496,860 shares of its $0.001 par value common stock. Subsequent to this conversion, the Company restated its certificate of incorporation and reduced number of authorized shares of preferred stock from 21,496,860 to 5,000,000. The Company’s preferred stock is undesignated.
	Common Stock
	The holders of common stock are entitled to one vote for each share. The voting, dividend and liquidation rights of the holders of common stock are subject to and qualified by the rights, powers and preferences of the holders of preferred stock.
	At December 31, 2014, the Company had reserved a total of 5,069,853 of its authorized 50,000,000 shares of common stock for future issuance as follows:
	Outstanding stock options	2,382,881
	Restricted stock units	720,370
	Possible future issuance under stock option plans	1,966,602
	Total common shares reserved for future issuance	5,069,853
	During 2009, in connection with a new five-year contract executed with a major customer, the Company issued a warrant to the customer for the right to purchase 500,000 shares of common stock at $5.48 per share. The warrant was issued from the incentive stock option pool of shares approved by the Company’s board of directors and had a term of 10 years. Under the terms of the warrant, the warrant expires in 10 years. The customer was originally entitled to exercise the warrant in its entirety in 9.5 years. Earlier exercise rights for all or part of the warrants are triggered under certain conditions, the most relevant of which are, on or after the third anniversary date of the issuance date if an IPO has occurred and immediately prior to the closing of a defined Corporate Transaction. In the event the customer cancels the contract prior to the end of the five-year term, one half of the warrants would have been forfeited. In March 2013, the Company made this warrant fully exercisable. In March 2014, the customer exercised the warrant through a cashless exercise in accordance with the warrant’s terms. The Company issued 455,521 shares to satisfy its obligation under the warrant.
	The Company used an option pricing model to determine the fair value of the common stock warrant. Significant inputs included an estimate of the fair value of the Company’s common stock, the remaining contractual life of the warrant, an estimate of the probability and timing of a liquidity event, a risk-free rate of interest and an estimate of the Company’s stock volatility using the volatilities of guideline peer companies. The value of the exercisable portion of the warrant is not dependent on the customer’s fulfillment of the contract and was measured on the issuance date, with the total fair value at issuance being recognized as a reduction to revenue over the contract period on the straight line basis. The remaining half of the warrant that was dependent on contract fulfillment by the customer was re-measured each quarter, with the resulting increment or decrement in value recognized as a revenue reduction on the straight line basis beginning in the quarter of the revaluation through the end of the contract. The related reduction of revenue during the years ended December 31, 2014, 2013 and 2012 was $744, $892, and $488, respectively. As of October 31, 2014, the fair value of the warrant had been fully recognized.

Employee_Benefit_Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2014
Employee Benefit Plan	12. Employee Benefit Plan
	The Company maintains a qualified defined contribution plan under Section 401(k) of the U.S. Internal Revenue Code (the “401(k) Plan”) covering substantially all employees. Employees are eligible to participate in the 401(k) Plan after one day of service and upon attainment of age 21, and may elect to defer an amount or percentage of their annual compensation up to amounts prescribed by law. The Company makes discretionary matching contributions to employee plan accounts. During each of the years ended December 31, 2014, 2013 and 2012, the Company matched 50% of the employees’ contribution, with the match limited to 3% of qualifying compensation. Employee vesting in matching company contributions occurs at a rate of 20% per year after achieving two years of service. Starting in 2014, employees vesting in company contributions began after one year of service. During the years ended December 31, 2014, 2013, and 2012, employer matching contributions were $2,083, $1,339 and $1,013, respectively.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Taxes	13. Income Taxes
	The Company files income tax returns in the U.S. for federal and various state jurisdictions. The Company is subject to U.S. federal income tax examination for calendar tax years 2007 through 2013 as well as state income tax examinations for various years depending on statutes of limitations of those jurisdictions.
	The following summarizes the components of income tax expense (benefit) for the years ended December 31:
		2014			2013			2012
	Current:
	Federal	$	—		$	—		$	—
	State and local		25			(31	)		84
	Total current expense (benefit)	$	25		$	(31	)	$	84
	Deferred:
	Federal	$	—		$	—		$	—
	State and local		—			—			—
	Total deferred taxes	$	—		$	—		$	—
	Reconciliation between the effect of applying the federal statutory rate and the effective income tax rate used to calculate the Company’s income tax provision is as follows for the years ended December 31:
		2014			2013			2012
	Federal statutory rate		34	%		34	%		34	%
	Effect of:
	State income taxes, net of federal benefit		4.8	%		3.2	%		3.5	%
	Change in tax rates		0.4	%		0.4	%		2.6	%
	State tax credits		0.4	%		0.9	%		0	%
	Change in valuation allowance		(39.3	%)		(33.5	%)		(38.7	%)
	Uncertain tax positions		0	%		(0.9	%)		0	%
	Contingent consideration amortization		0	%		0	%		(0.4	%)
	Stock-based compensation		(0.2	%)		(0.9	%)		(1.2	%)
	Other permanent items		(0.1	%)		(0.4	%)		(0.4	%)
	Deferred tax true-up		0	%		(2.7	%)		0	%
	Income tax provision effective rate		0	%		0.1	%		(0.6	%)
	The significant components of the Company’s deferred tax asset and liability were as follows as of December 31:
		2014			2013
	Deferred tax assets relating to:
	Net operating loss carryforwards	$	26,132		$	15,553
	Deferred revenue		23,612			16,779
	Commissions and incentive accrual		1,771			463
	Deferred rent		816			1,027
	State tax credits		3,195			2,961
	Stock-based compensation		1,993			1,615
	Compensation and other accruals		3,964			1,361
	Total gross deferred tax assets		61,483			39,759
	Deferred tax liabilities:
	Prepaid expenses	$	—		$	(727	)
	Property and equipment, financing obligations and intangible assets		(2,514	)		(4,610	)
	Total gross deferred tax liabilities		(2,514	)		(5,337	)
	Deferred tax assets less liabilities		58,969			34,422
	Less: valuation allowance		(58,969	)		(34,422	)
	Net deferred tax asset (liability)	$	—		$	—
	As of December 31, 2014 and 2013, the Company’s gross deferred tax was reduced by a valuation allowance of $58,969 and $34,422 respectively.
	The valuation allowance increased by $24,547 and $10,191 during the years ended December 31, 2014 and 2013, respectively. The valuation allowance increase resulted primarily from changes in the deferred tax assets related to the net operating loss carryforwards and deferred revenue.
	In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income, and tax planning strategies in making this assessment. Based upon the level of historical taxable income and projections for future taxable income over the periods in which the deferred tax assets are deductible, management believes it is more likely than not that the Company will not realize the benefits of these deductible differences in the future. In recognition of this risk, the Company has provided a full valuation allowance on the deferred tax assets relating to net operating loss carryforwards. The Company’s $30,749 of federal and state net operating losses include excess tax benefits related to deductions from the exercise of nonqualified stock options. The tax benefit of these deductions has not been recognized in deferred tax assets. If utilized, $5,024 of benefits from these deductions will be recorded as adjustments to taxes payable and additional paid-in-capital.
	Net operating loss carryforwards for federal income tax purposes were approximately $68,235 and $41,374 at December 31, 2014 and 2013, respectively. State net operating loss carryforwards were $61,583 and $33,665 at December 31, 2014 and 2013, respectively. The federal net operating loss carryforwards will expire at various dates beginning in 2022 through 2033, if not utilized. Net operating loss carryforwards and credit carryforwards reflected above may be limited due to historical and future ownership changes.
	South Carolina jobs tax credit and headquarters tax credit carryovers of $5,277 and $4,497 were available at December 31, 2014 and 2013, respectively. Headquarters credits are expected to be used to offset future state income tax license fees. The credits expire in various amounts during 2020 through 2028.
	The Company follows FASB ASC 740-10 for accounting for unrecognized tax benefits. As of December 31, 2014, the Company had gross unrecognized tax benefits of $437.
	A reconciliation of the beginning and ending amounts of unrecognized tax benefits is as follows for the year ended December 31, 2014 and 2013 (no unrecognized tax benefits in 2012):
		2014			2013
	Balance at beginning of year	$	437		$	—
	Additions based on tax positions related to the current year		—			—
	Additions for tax positions in prior years		—			437
	Reductions for tax positions of prior years		—			—
	Reductions for tax positions due to lapse of statute		—			—
	Settlements		—			—
	Balance at end of year	$	437		$	437
	At December 31, 2014 and 2013, none of the $437 liabilities for unrecognized tax benefits could impact the Company’s effective tax rate, if recognized. The Company does not expect the unrecognized tax benefits to change within the next twelve months.
	The Company is subject to U.S. income taxes, as well as various taxes state and local jurisdictions. With few exceptions, the Company is no longer subject to U.S. federal, state, and local income tax examinations by tax authorities for years before the tax year ended December 31, 2011, although carryforward attributes that were generated prior to 2011 may still be adjusted upon examination by the taxing authorities if they either have been used or will be used in a future period.

Segments_and_Geographic_Inform

Segments and Geographic Information	12 Months Ended
	Dec. 31, 2014
Segments and Geographic Information	14. Segments and Geographic Information
	Operating segments are defined as components of an enterprise for which discrete financial information is available that is evaluated regularly by the chief operating decision maker (“CODM”) for purposes of allocating resources and evaluating financial performance. The Company’s CODM, the Chief Executive Officer, reviews financial information presented on a consolidated basis, accompanied by information about operating segments, for purposes of allocating resources and evaluating financial performance.
	The Company’s reportable segments are based on the type of customer. The Company determined its operating segments to be: Employer, which derives substantially all of its revenue from customers that use the Company’s services for the provision of benefits to their employees, and administrators acting on behalf of employers; and Carrier, which derives substantially all of its revenue from insurance companies that provide coverage at their own risk.
	During 2014, the Company changed how it evaluates its operating segments. It no longer reports operating income by segment to the CODM. Segments are evaluated based on gross profit. The Company does not allocate interest income, interest expense or income tax expense by segment. Accordingly, the Company does not report such information. Additionally, Employer and Carrier segments share the majority of the Company’s assets. Therefore, no segment asset information is reported.
		Year Ended December 31,
		2014		2013		2012
	Revenue from external customers by segment:
	Employer	$	62,016	$	40,656	$	23,760
	Carrier		75,404		64,096		57,979
	Total net revenue from external customers	$	137,420	$	104,752	$	81,739
	Depreciation and amortization by segment:
	Employer	$	4,392	$	3,035	$	2,337
	Carrier		5,101		5,137		6,223
	Total depreciation and amortization	$	9,493	$	8,172	$	8,560
	Gross profit by segment
	Employer	$	16,186	$	13,316	$	9,810
	Carrier		33,764		29,025		27,529
	Total gross profit by segment	$	49,950	$	42,341	$	37,339
	Substantially all assets were held and all revenue was generated in the United States during the years ended December 31, 2014, 2013 and 2012.

Related_Parties

Related Parties	12 Months Ended
	Dec. 31, 2014
Related Parties	15. Related Parties
	Related Party Leasing Arrangements
	The Company leases its office space at its Charleston, South Carolina headquarters campus under the terms of two non-cancellable leases from an entity with which two of the Company’s directors, significant stockholders, and executives are affiliated. The Company’s headquarters building is accounted for as a build-to-suit lease and recorded as a financing obligation in the Consolidated Balance Sheets. Additional office space is accounted for as an operating lease. Both the financing obligation and the operating lease have 15-year terms which started in 2006 and 2009, respectively. The Company has an option to renew the leases for five additional years. The arrangements provide for 3.0% fixed annual rent increases.
	In February 2013, the Company entered into an amendment to a 2009 operating lease agreement. Under terms of the agreement, the Company committed to rent additional space under the agreement. Payments for the additional space commenced in January 2014.
	Furthermore, as disclosed in Note 9 “Commitments and Contingencies”, the Company entered into a 15-year build-to-suit lease in December 2013 for additional office space to expand its headquarters campus. The leased premises are being constructed and leased from an entity with which two of the Company’s significant stockholders and executives are affiliated. Because the Company is involved extensively in the construction of the premises and is deemed the “owner” for accounting purposes during the construction period, it is required to capitalize the project costs during the construction on its Consolidated Balance Sheet. The lease will commence in January 2015. As of December 31, 2014, financing obligations included $20,124 related to this build-to-suit lease.
	The Company has options to lease two additional office facilities from the leasing entity with which two of the Company’s directors, significant stockholders and executives are affiliated. The leasing entity meets the criteria to be a variable interest entity. The Company is not the primary beneficiary of the leasing entity, as the activities that are most significant to the leasing entity’s economic performance, consisting of financing, development, management, and sale of office facilities, are directed by another party. As such, the Company is not required to consolidate the entity as the primary beneficiary. The lease terms would not include a residual value guarantee, fixed-price purchase option, or similar feature that would obligate the Company to absorb decreases in value or would entitle the Company to participate in increases in the value of the office facilities. The Company has not and does not intend to provide financial or other support to the leasing entity. The Company’s maximum exposure, assuming the exercise of the options, would consist of carrying fees paid for the options, rent to be paid over the 15-year term of the leases, construction cost overruns, and operating expenses in excess of a certain threshold. The Company’s maximum exposure currently cannot be quantified.
	Payments related to these agreements were $5,634, $3,729, and $3,834 for the years ended December 31, 2014, 2013 and 2012, respectively. Amounts due to the related parties were $1,807 and $268 as of December 31, 2014 and 2013, respectively. Amounts due to the related parties were recorded as $949 in “Accounts Payable” and $858 in “Accrued Expenses” as of December 31, 2014 and $268 in “Accounts Payable” as of December 31, 2013.
	Related Party Travel Expenses
	The Company utilizes the services of a private air transportation companies that are owned and controlled by one of the Company’s significant stockholders and executives. Expenses related to these companies were $438, $345 and $125 for the years ended December 31, 2014, 2013 and 2012 respectively, and consist of air travel related to the operations of the business. Amounts due to the related party were $44 as of December 31, 2014 and $25 as of December 31, 2013.

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2014
Selected Quarterly Financial Data (unaudited)	16. Selected Quarterly Financial Data (unaudited)
	The following tables set forth selected unaudited quarterly statements of operations data for each of the eight quarters in the years ended December 31, 2014 and 2013.
			Quarter Ended
			December 31,			September 30,			June 30,			March 31,			December 31,			September 30,			June 30,			March 31,
			2014 (b)			2014			2014			2014			2013			2013			2013			2013
	Consolidated Statements of Operations Data:
	Revenue		$	40,187		$	34,200		$	32,337		$	30,696		$	30,256		$	26,317		$	24,332		$	23,847
	Gross profit			16,335			10,845			11,300			11,470			10,783			10,146			10,010			11,402
	Total operating expenses			28,241			28,607			28,711			23,294			18,474			16,504			19,091			16,466
	Operating loss			(11,906	)		(17,762	)		(17,411	)		(11,824	)		(7,691	)		(6,358	)		(9,081	)		(5,064	)
	Net loss		$	(13,689	)	$	(18,888	)	$	(18,200	)	$	(12,402	)	$	(8,282	)	$	(6,836	)	$	(9,628	)	$	(5,615	)
	Net loss per common share (a)			(0.54	)		(0.74	)		(0.72	)		(0.51	)		(0.34	)		(1.08	)		(2.00	)		(1.17	)
	Weighted-average common shares outstanding— basic and diluted			25,569,203			25,503,194			25,200,093			24,541,359			24,474,566			6,320,731			4,809,518			4,798,043
	(a)	Quarterly and year-to-date computations of per share amounts are made independently. Therefore, the sum of the per-share amounts for the quarters may not agree with per share amounts for the year.
	(b)	During the fourth quarter of 2014, the Company recorded a cumulative adjustment to correct prior period errors that related to an overstatement of amortization of certain capitalized software costs. The impact of these items on the Company’s Consolidated Statement of Operations decreased cost of revenue, increased gross profit, and decreased loss from operations, loss before income taxes, and net loss by $628. The Company did not adjust the prior periods as it concluded that such adjustments were not material to the current or prior period Consolidated Financial Statements.
	The quarterly unaudited consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements included in this report and include all adjustments, consisting only of normal recurring adjustments, that we consider necessary for a fair presentation of such information when read in conjunction with our annual audited consolidated financial statements (as restated) and notes appearing in this report. The operating results for any quarter do not necessarily indicate the results for any subsequent period or for the entire fiscal year.

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2014
Subsequent Events	17. Subsequent Events
	Restricted Stock Units
	During January 2015, the Company granted 26,050 restricted stock units to employees with an aggregate grant date fair value of $815. These restricted stock units vest in equal annual installments generally over 4 years from the grant date. The Company amortizes the fair value of the stock subject to the restricted stock units at the time of grant on a straight-line basis over the period of vesting. The Company recognizes the income tax benefits resulting from vesting of restricted stock units in the period they vest, to the extent the compensation expense has been recognized.
	Build-to-Suit Lease
	During January 2015, the Company began to occupy the additional office space constructed under the 15-year build-to-suit lease signed in December 2013. During the construction of the premises, the Company was deemed the “owner” for accounting purposes due to its extensive involvement in the construction process. Upon completion, the Company was also deemed the “owner” for accounting purposes. As such, $18,243 included in “Construction-in-Progress” related to the construction of this premises at December 31, 2014, will be allocated to “Buildings, leased.” Any additional capitalizable costs incurred as part of the completion of construction will be allocated to the asset. Also, related to occupying this building, other amounts included in “Construction-in-Progress” at December 31, 2014 will be allocated to the applicable property and equipment category as follows: $2,346 to “Furniture and fixtures,” $2,277 to “Leasehold improvements,” and $764 to “Computers and related equipment.”
	Revolving Line of Credit
	In February 2015, the Company replaced its existing revolving line of credit (“Revolver”) with a senior revolving line of credit (“Senior Revolver”) with a syndicate of lenders led by the existing lender. Outstanding balances under the Revolver were repaid with proceeds from the Senior Revolver and the Revolver was terminated. The three-year Senior Revolver has a borrowing limit of $60,000. Borrowing capacity under the Senior Revolver is subject to a borrowing base limit that is a function of the Company’s monthly recurring revenue as adjusted to reflect lost customer revenue during the previous three calendar months. Therefore, credit available under the Senior Revolver may be less than the $60,000 borrowing limit. Interest is payable monthly. Advances under the Senior Revolver bear interest at the prime rate as published in the Wall Street Journal plus a margin based on the Company’s liquidity that ranges between 1.0% and 1.5%. The Company is charged for amounts unused under this arrangement at a rate based on its liquidity of 0.300% to 0.375% per year. Any outstanding principal is due at the end of the term.
	The Company is bound by customary affirmative and negative covenants in connection with the Senior Revolver, including financial covenants related to liquidity and EBITDA. In the event of a default, the lenders may declare all obligations immediately due and stop advancing money or extending credit under the line of credit. The line of credit is collateralized by substantially all of the Company’s tangible and intangible assets, including intellectual property and the equity of subsidiaries.
	Common Stock
	On February 24, 2015, the Company entered into a Securities Purchase Agreement to sell shares of its common stock to Mercer, LLC (“Mercer”), a customer of the Company. Pursuant to the agreement, on the same date, the Company sold 2,817,526 shares of its common stock to Mercer for $26.50 per share or an aggregate of $74,664. At the same time, the Company also issued Mercer a warrant to purchase up to an additional 580,813 shares of its common stock for $26.50 per share at any time during the 30-month term of the warrant. The agreement, among other things, includes certain standstill provisions and prevents Mercer from disposing of its shares of Company common stock until the earlier of December 31, 2017, the expiration or termination of the Mercer Exchange Software as a Service Agreement, as amended between the Company and Mercer Health & Benefits, LLC, the date on which Mercer and its affiliates own less than 75% of the shares it purchased pursuant to the Securities Purchase Agreement, and the date on which Mercer and its affiliates own less than 5% of the outstanding common stock of the Company. The Company received all of the proceeds from this sale of shares and will use the proceeds for working capital and other general corporate purposes.

Schedule_IIValuation_and_Quali

Schedule II-Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2014
Schedule II-Valuation and Qualifying Accounts
	Schedule II—Valuation and Qualifying Accounts (in thousands)
			Balance at		Additions			Additions		Deductions			Balance
			Beginning		Charged To			Charged					at End of
			of Period		Expense			Against					Period
								Revenue
	Allowance for doubtful accounts and returns:
	Year Ended December 31, 2014		$	810	$	94		$	4,585	$	(3,826	)	$	1,663
	Year Ended December 31, 2013		$	900	$	(22	)	$	2,315	$	(2,383	)	$	810
	Year Ended December 31, 2012		$	358	$	98		$	1,330	$	(886	)	$	900
			Balance at		Additions			Deductions		Balance
			Beginning		Charged To					at End of
			of Period		Costs and					Period
					Expenses (1)
	Deferred tax asset valuation allowance:
	Year Ended December 31, 2014		$	34,422	$	24,547		$	—	$	58,969
	Year Ended December 31, 2013		$	24,231	$	10,191		$	—	$	34,422
	Year Ended December 31, 2012		$	18,510	$	5,721		$	—	$	24,231
	-1	Increase in valuation allowance is related to the generation of net operating losses and other deferred tax assets.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Principles of Consolidation	Principles of Consolidation
	These consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. We are not the primary beneficiary of, nor do we have a controlling financial interest in, any variable interest entity. Accordingly, we have not consolidated any variable interest entity.
Use of Estimates	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. Such estimates include revenue recognition and the customer relationship period, allowances for doubtful accounts and returns, valuations of deferred income taxes, long-lived assets, warrants, the useful lives of assets, capitalizable software development costs and the related amortization, contingent consideration, stock-based compensation, and the recognition and impairment assessment of acquired intangibles and goodwill. Determination of these transactions and account balances are based on the Company’s estimates and judgments. These estimates are based on the Company’s knowledge of current events and actions it may undertake in the future as well as on various other assumptions that it believes to be reasonable. Actual results could differ materially from these estimates.
Revenue and Deferred Revenue	Revenue and Deferred Revenue
	The Company derives the majority of its revenue from software services fees, which consist primarily of monthly subscription fees paid by customers for access to and usage of the Company’s cloud-based benefits software solutions for a specified contract term. The Company also derives revenue from professional services which primarily include fees related to the integration of customers’ systems with the Company’s platform, which typically includes discovery, configuration, deployment, testing, and training.
	The Company recognizes revenue when there is persuasive evidence of an arrangement, the service has been provided, the fees to be paid by the customer are fixed and determinable and collectability is reasonably assured. The Company considers delivery of its cloud-based software services has commenced once it has granted the customer access to its platform.
	The Company’s arrangements generally contain multiple elements comprised of software services and professional services. The Company evaluates each element in an arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. The Company’s professional services are not sold separately from the software services and there is no alternative use for them. As such, the Company has determined that the professional services do not have standalone value. Accordingly, software services and professional services are combined and recognized as a single unit of accounting.
	The Company generally recognizes software services fees monthly based on the number of employees covered by the relevant benefits plans at contracted rates for a specified period of time, once the criteria for revenue recognition described above have been satisfied. The Company defers recognition of revenue for professional services fees and begins recognizing such revenue once the services are performed and the related software services have commenced, ratably over the longer of the contract term or the estimated expected life of the customer relationship. Costs incurred by the Company in connection with providing such professional services are charged to expense as incurred and are included in “Cost of revenue.”
	In January 2015, the Company adjusted the estimated expected life of its customer relationship. This change in estimate was the result of analyzing quantitative and qualitative observations in the market and the Company’s business. This change shortens the term over which deferred revenue will be recognized from 10 to 7 years and will be applied prospectively to unamortized professional services fees over the longer of the contract term or the adjusted estimated expected life of the customer relationship.
Cost of Revenue	Cost of Revenue
	Cost of revenue primarily consists of employee compensation, professional services, data center co-location costs, networking expenses, depreciation expense for computer equipment directly associated with generating revenue, amortization expense for capitalized software development costs, and infrastructure maintenance costs. In addition, the Company allocates a portion of overhead, such as rent, additional depreciation and amortization expense, and employee benefit costs, to cost of revenue based on headcount.
Cash and Cash Equivalents	Cash and Cash Equivalents
	Cash and cash equivalents consist of bank checking accounts and money market accounts. The Company considers all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents.
Marketable Securities	Marketable Securities
	Marketable securities consist of short-term investments in corporate securities. The Company classifies its marketable securities as held-to-maturity at the time of purchase. As a result, the marketable securities are recorded at amortized cost and any gains or losses realized upon maturity are reported in other expense, net in the consolidated statements of operations and comprehensive loss.
Concentrations of Credit Risk	Concentrations of Credit Risk
	The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash equivalents and accounts receivable. All of the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. The bank deposits of the Company might, at times, exceed federally insured limits and are generally uninsured and uncollateralized. The Company has not experienced any losses on cash and cash equivalents to date. To manage accounts receivable risk, the Company evaluates the creditworthiness of its customers and maintains an allowance for doubtful accounts.
	Accounts receivable were unsecured and were derived from revenue earned from customers located in the United States. Accounts receivable from one customer, Aetna, represented 13.3% and 11.3% of the total accounts receivable at December 31, 2014 and 2013, respectively.
	No customer represented more than 10% of total revenue for the years ended December 31, 2014 and 2013. Revenue from one customer, Aetna, represented 10.5% of total revenue for the year ended December 31, 2012. Revenue from this customer is reported in the Company’s Carrier segment.
Accounts Receivable and Allowance for Doubtful Accounts and Returns	Accounts Receivable and Allowance for Doubtful Accounts and Returns
	Accounts receivable is stated at realizable value, net of allowances for doubtful accounts and returns. The Company utilizes the allowance method to provide for doubtful accounts based on management’s evaluation of the collectability of amounts due, and other relevant factors. Bad debt expense is recorded in general and administrative expense on the consolidated statements of operations and comprehensive loss. The Company’s estimate is based on historical collection experience and a review of the current status of accounts receivable. Historically, actual write-offs for uncollectible accounts have not significantly differed from the Company’s estimates. The Company removes recorded receivables and the associated allowances when they are deemed permanently uncollectible. However, higher than expected bad debts may result in future write-offs that are greater than the Company’s estimates. The allowance for doubtful accounts was $10 as of December 31, 2014 and 2013.
	The allowances for returns are accounted for as reductions of revenue and are estimated based on the Company’s periodic assessment of historical experience and trends. The Company considers factors such as the time lag since the initiation of revenue recognition, historical reasons for adjustments, new customer volume, complexity of billing arrangements, timing of software availability, and past due customer billings. The allowance for returns was $1,653 and $800 as of December 31, 2014 and 2013, respectively.
Property and Equipment	Property and Equipment
	Property and equipment, including capitalized software development costs, are stated at cost less accumulated depreciation and amortization. Expenditures for major additions and improvements are capitalized. Depreciation and amortization is recognized over the estimated useful lives of the related assets using the straight-line method.
	The estimated useful lives for significant property and equipment categories are generally as follows:
	Computers and related equipment	3-7 years
	Furniture and fixtures	7 years
	Other equipment	5-12 years
	Purchased software and licenses	1-7 years
	Vehicles	5 years
	Buildings	30 years
	Leasehold improvements	Lesser of estimated useful life of asset or lease term
	Useful lives of significant assets are periodically reviewed and adjusted prospectively to reflect the Company’s current estimates of the respective assets’ expected utility. Costs associated with maintenance and repairs are expensed as incurred.
	In the event the Company has been deemed the owner for accounting purposes of construction projects in build-to-suit lease arrangements, the estimated construction costs incurred to date are recorded as assets in Property and Equipment, net. Upon occupancy of facilities under build-to-suit leases, the Company assesses whether arrangements qualify for sales recognition under the sale-leaseback accounting guidance. If the Company continues to be the deemed owner for accounting purposes, the cost of the building is depreciated over its estimated useful life.
Capitalized Software Development Costs	Capitalized Software Development Costs
	The Company capitalizes certain costs related to its software developed or obtained for internal use. Costs related to preliminary project activities and post-implementation activities are expensed as incurred. Internal and external costs incurred during the application development stage, including upgrades and enhancements representing modifications that will result in significant additional functionality, are capitalized. Software maintenance and training costs are expensed as incurred. Capitalized costs are recorded as part of property and equipment and are amortized on a straight-line basis over the software’s estimated useful life which is three years. The Company evaluates these assets for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets.
Identifiable Intangible Assets	Identifiable Intangible Assets
	Identifiable intangible assets with finite lives are recorded at their fair values at the date of acquisition and are amortized on a straight-line basis over their respective estimated useful lives, which is the period over which the asset is expected to contribute directly or indirectly to future cash flows. The estimated remaining useful lives used in computing amortization range from 1 to 4 years.
Impairment of Long-Lived Assets and Goodwill	Impairment of Long-Lived Assets and Goodwill
	The Company reviews long-lived assets and definite-lived intangible assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Recoverability of the long-lived asset is measured by a comparison of the carrying amount of the asset or asset group to future undiscounted net cash flows expected to be generated. If such assets are not recoverable, the impairment to be recognized, if any, is measured as the amount by which the carrying amount of the assets exceeds the estimated fair value (discounted cash flow) of the assets or asset group. Assets held for sale are reported at the lower of the carrying amount or fair value, less costs to sell.
	Goodwill represents the excess of the aggregate of the fair value of consideration transferred in a business combination over the fair value of assets acquired, net of liabilities assumed. Goodwill is not amortized; rather, goodwill is tested for impairment at the reporting unit level as of October 31 of each year, or more frequently if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value.
	The Company performs a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying value before performing a two-step approach to testing goodwill for impairment for each reporting unit. The reporting units are determined by the components of the Company’s operating segments that constitute a business for which both (1) discrete financial information is available and (2) segment management regularly reviews the operating results of that component. If it is more likely than not that the fair value of a reporting unit is less than its carrying value, the Company performs the impairment test by applying a fair-value-based test. The first step measures for impairment by applying fair-value-based tests at the reporting unit level. The second step (if necessary) measures the amount of impairment by applying fair-value-based tests to the individual assets and liabilities within each reporting unit.
	As part of determining its reporting units, the Company has identified two operating segments, Employer and Carrier. To determine the fair value of the Company’s reporting units, the Company has used a discounted cash flow analysis, which requires significant assumptions and estimates about future operations. Significant judgments inherent in this analysis include the determination of an appropriate discount rate, estimated terminal value and the amount and timing of expected future cash flows. The Company may also determine fair value of its reporting units using a market approach by applying multiples of earnings of peer companies to its operating results.
Financing Obligations	Financing Obligations
	In its build-to-suit lease arrangements where the Company is involved in the construction of its buildings, the Company is deemed the owner for accounting purposes during the construction period. The Company records an asset for the amount of the total project costs in Property and Equipment, net and the related financing obligation in Financing and Capital Lease Obligations on the Consolidated Balance Sheet. Once construction is complete, the Company determines if the asset qualifies for sale-leaseback accounting treatment. If the arrangement does not qualify for sale-lease back treatment, the Company continues to reduce the obligation over the lease term as payments are made and depreciates the asset over its useful life. The Company does not report rent expense for the portion of the rent payment determined to be related to the assets which are owned for accounting purposes. Rather, this portion of the rent payment under the lease is recognized as a reduction of the financing obligation and as interest expense.
	Financing obligations also include liabilities for service agreements related to property and equipment under capital leases.
Sales Commissions	Sales Commissions
	Sales commissions are expensed when the sales contract is executed by the customer.
Advertising	Advertising
	The Company expenses advertising costs as they are incurred. Direct advertising costs for 2014, 2013, and 2012 were $394, $265, and $257, respectively.
Comprehensive Loss	Comprehensive Loss
	The Company’s net loss equals comprehensive loss for all periods presented.
Stock-Based Employee Compensation	Stock-Based Employee Compensation
	Stock-based employee compensation is measured based on the grant-date fair value of the awards and recognized in the Consolidated Statements of Operations and Comprehensive Loss over the period during which the award holder is required to perform services in exchange for the award, which is the vesting period. Compensation expense is recognized over the vesting period of the applicable award using the straight-line method. Compensation costs related to restricted stock units (‘RSUs’) is recorded based on the market price on the grant date. The Company uses the Black-Scholes option pricing model for estimating the fair value of stock options. The use of the option valuation model requires the input of subjective assumptions, including the estimated fair value of the Company’s common stock in the periods preceding the IPO, the expected life of the option and the expected stock price volatility based on peer companies. Additionally, the recognition of stock-based compensation expense requires the estimation of the number of options that will ultimately vest and the number of options that will ultimately be forfeited.
Income Taxes	Income Taxes
	The Company uses the asset and liability method for income tax accounting. This method requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax basis of assets and liabilities, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled. Valuation allowances are recorded to reduce deferred tax assets to the amount the Company believes is more likely than not to be realized. The tax benefits of uncertain tax positions are recognized only when the Company believes it is more likely than not that the tax position will be upheld on examination by the taxing authorities based on the merits of the position. The Company recognizes interest and penalties, if any, related to unrecognized income tax benefits in income tax expense.
Basic and Diluted Net Loss per Common Share	Basic and Diluted Net Loss per Common Share
	The Company uses the two-class method to compute net loss per common share because the Company has issued securities, other than common stock, that contractually entitle the holders to participate in dividends and earnings of the Company. The two-class method requires earnings for the period to be allocated between common stock and participating securities based upon their respective rights to receive distributed and undistributed earnings. Holders of each series of the Company’s redeemable convertible preferred stock are entitled to participate in distributions, when and if declared by the board of directors that are made to common stockholders, and as a result are considered participating securities.
	Under the two-class method, for periods with net income, basic net income per common share is computed by dividing the net income attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Net income attributable to common stockholders is computed by subtracting from net income the portion of current year earnings that the participating securities would have been entitled to receive pursuant to their dividend rights had all of the year’s earnings been distributed. No such adjustment to earnings is made during periods with a net loss, as the holders of the participating securities have no obligation to fund losses. Diluted net loss per common share is computed under the two-class method by using the weighted-average number of shares of common stock outstanding plus, for periods with net income attributable to common stockholders, the potential dilutive effects of stock awards and warrants. In addition, the Company analyzes the potential dilutive effect of the outstanding participating securities under the “if-converted” method when calculating diluted earnings per share, in which it is assumed that the outstanding participating securities convert into common stock at the beginning of the period. The Company reports the more dilutive of the approaches (two-class or “if-converted”) as its diluted net income per share during the period. Due to net losses for the years ended December 31, 2014, 2013, and 2012 basic and diluted loss per share were the same, as the effect of potentially dilutive securities would have been anti-dilutive.
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	In May 2014, the FASB issued ASU No. 2014-09 “Revenue from Contracts with Customers”, which amends the revenue recognition requirements in the FASB Accounting Standards Codification (ASC). This statement requires that an entity recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The statement shall be applied using one of two methods: retrospectively to each prior reporting period presented, or retrospectively with the cumulative effect of initially applying this statement recognized at the date of initial application. The Company has not yet determined which method it will apply. This statement is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. The Company is currently evaluating the impact of this guidance on the Company’s consolidated financial position and results of operations.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Estimated Useful Lives for Significant Property and Equipment	The estimated useful lives for significant property and equipment categories are generally as follows:
	Computers and related equipment	3-7 years
	Furniture and fixtures	7 years
	Other equipment	5-12 years
	Purchased software and licenses	1-7 years
	Vehicles	5 years
	Buildings	30 years
	Leasehold improvements	Lesser of estimated useful life of asset or lease term

Net_Loss_Per_Common_Share_Tabl

Net Loss Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2014
Common Share Equivalent Securities Excluded from Calculation of Weighted-Average Common Shares Outstanding	The following common share equivalent securities have been excluded from the calculation of weighted-average common shares outstanding because the effect is anti-dilutive for the periods presented:
		Year Ended December 31,
	Anti-Dilutive Common Share Equivalents	2014			2013			2012
	Redeemable convertible preferred stock:
	Series A		—			—			14,055,851
	Series B		—			—			2,441,009
	Restricted stock units		720,370			97,700			—
	Stock options		2,382,881			3,058,795			3,121,064
	Warrant to purchase common stock		—			500,000			500,000
	Total anti-dilutive common share equivalents		3,103,251			3,656,495			20,117,924
Basic and Diluted Net Loss per Common Share	Basic and diluted net loss per common share is calculated as follows:
		Year Ended December 31,
		2014			2013			2012
	Numerator:
	Net loss	$	(63,179	)	$	(30,361	)	$	(14,873	)
	Net loss attributable to common stockholders	$	(63,179	)	$	(30,361	)	$	(14,873	)
	Denominator:
	Weighted-average common shares outstanding, basic and diluted		25,207,099			10,144,243			4,812,632
	Net loss per common share, basic and diluted	$	(2.51	)	$	(2.99	)	$	(3.09	)

Marketable_Securities_Tables

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2014
Investments In Unrealized Loss Position For Which Other-Than-Temporary Impairment not Recognized in Earnings	The following table presents information about the Company’s investments that were in an unrealized loss position and for which an other-than-temporary impairment has not been recognized in earnings as of December 31:
			2014			2013
	Aggregate fair value of investments with unrealized losses (1)		$	5,135		$	1,281
	Aggregate amount of unrealized losses			(1	)		(2	)
	-1	Investments have been in a continuous loss position for less than 12 months

Fair_Value_Measurement_Tables

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2014
Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis using the above categories, as of December 31, 2014 and 2013.
			December 31, 2014
	Description		Level 1			Level 2		Level 3		Total
	Cash Equivalents:
	Money market mutual funds (1)		$	50,695		$	—	$	—	$	50,695
	Total assets		$	50,695		$	—	$	—	$	50,695
			December 31, 2013
	Description		Level 1			Level 2		Level 3		Total
	Cash Equivalents:
	Money market mutual funds (1)		$	65,443		$	—	$	—	$	65,443
	Total assets		$	65,443		$	—	$	—	$	65,443
	-1	Money market funds are classified as cash equivalents in the Company’s consolidated balance sheets. As short-term, highly liquid investments readily convertible to known amounts of cash, with remaining maturities of three months or less at the time of purchase, the Company’s cash equivalent money market funds have carrying values that approximate fair value.
Changes in Level 3 Instruments Measured at Fair Value on Recurring Basis	The following table presents the changes in the Company’s Level 3 instruments measured at fair value on a recurring basis for the year ended December 31, 2013 (no such assets in 2014):
			2013
	Balance of contingent consideration at beginning of period		$	328
	Change in fair value			(43	)
	Accretion of discount			26
	Payment			(311	)
	Balance of contingent consideration at end of period		$	—

Property_and_Equipment_Tables

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2014
Property and Equipment	Property and equipment consists of the following as of December 31:
		2014			2013
	Building, leased	$	7,965		$	7,965
	Computers and related equipment		18,871			13,954
	Purchased software and licenses		20,392			17,556
	Software developed		18,397			16,182
	Furniture and fixtures		3,834			2,717
	Leasehold improvements		3,334			1,730
	Other equipment		2,009			1,922
	Vehicles		111			111
	Construction in progress		24,296			1,781
	Total property and equipment, at cost		99,209			63,918
	Accumulated depreciation and amortization		(45,188	)		(36,474	)
	Property and equipment, net	$	54,021		$	27,444

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Acquisition-Related Intangible Assets	Information regarding the Company’s acquisition-related intangible assets is as follows:
		As of December 31, 2014
		Gross		Accumulated			Net Carrying		Weighted-
		Carrying		Amortization			Amount		Average
		Amount							Remaining
									Useful Life
									(in years)
	Trademarks	$	240	$	(212	)	$	28		0.6
	Customer agreements		2,060		(1,137	)		923		3.6
	Non-compete agreements		126		(126	)		—		—
	Total	$	2,426	$	(1,475	)	$	951		3.5
		As of December 31, 2013
		Gross		Accumulated			Net Carrying		Weighted-
		Carrying		Amortization			Amount		Average
		Amount							Remaining
									Useful Life
									(in years)
	Trademarks	$	240	$	(164	)	$	76		1.6
	Customer agreements		2,060		(880	)		1,180		4.6
	Non-compete agreements		126		(126	)		—		—
	Total	$	2,426	$	(1,170	)	$	1,256		4.4
Expected Amortization Expense for the Intangible Assets	As of December 31, 2014, expected amortization expense for the intangible assets for each of the next five years and thereafter was as follows:
	2015	$	286
	2016		257
	2017		257
	2018		151
	2019		—
	Total	$	951

Commitment_and_Contingencies_T

Commitment and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Future Minimum Operating Lease Payments	Future minimum lease payments are as follows:
		Operating
		Leases
	Year Ending December 31,
	2015	$	3,857
	2016		3,912
	2017		3,934
	2018		3,747
	2019		3,841
	Thereafter		20,110
	Total minimum lease payments	$	39,401
Financing Obligations	Financing Obligations are allocated as follows:
		As of December 31,
		2014			2013
	Headquarters building, build-to-suit	$	8,873		$	9,023
	Software support		2,700			3,872
	Construction in progress, build-to-suit		20,124			202
	Total financing obligations	$	31,697		$	13,097
	Less: current portion		(1,720	)		(1,702	)
	Financing obligations, net of current portion	$	29,977		$	11,395
Future Minimum Lease Payments	Future minimum lease payments are as follows:
		Capital			Financing
		Leases			Obligations
	Year Ending December 31,
	2015	$	2,621		$	7,462
	2016		1,998			7,185
	2017		323			6,265
	2018		2			6,407
	2019		—			6,599
	Thereafter		—			55,983
	Total minimum lease and financing obligation payments		4,944		$	89,901
	Less: imputed interest		(204	)
	Less: current portion		(2,477	)
	Capital lease obligations, net of current portion	$	2,263

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2014
Number of Awards Outstanding	The Company has issued two types of awards under these plans: options and restricted stock units. The following table sets forth the number of awards outstanding for each award type is as follows:
		Outstanding at December 31,
	Award type	2014			2013		2012
	Stock options		2,382,881			3,058,795		3,121,064
	Restricted stock units		720,370			97,700		—
Stock-Based Compensation Expense Related to Stock Options	Stock-based compensation expense related to stock-based awards is included in the following line items in the accompanying consolidated statements of operations and comprehensive loss for the years ended December 31:
		2014			2013		2012
	Cost of revenue	$	986		$	274	$	195
	Sales and marketing		1,395			171		68
	Research and development		1,376			255		130
	General and administrative		1,831			502		319
		$	5,588		$	1,202	$	712
Summary of Unvested Restricted Stock Units Activity	The summary of unvested restricted stock units is as follows:
		Restricted			Weighted
		stock units			average
					grant date
					fair value
	Unvested at December 31, 2013		97,700		$	48.31
	Granted		679,587			37.97
	Forfeited		(33,175	)		46.87
	Vested		(23,742	)		48.23
	Unvested at December 31, 2014		720,370		$	38.63
Summary of Option Activity	The following is a summary of the option activity for the year ended December 31, 2014:
		Number of			Weighted-		Weighted-		Aggregate
		Options			Average		Average		Intrinsic Value
					Exercise		Remaining
					Price		Contractual
							Term
							(in years)
	Outstanding balance at December 31, 2013		3,058,795		$	6.75
	Granted		—			—
	Exercised		(642,152	)		4.39
	Forfeited		(31,664	)		9.98
	Expired		(2,098	)		1.38
	Outstanding balance at December 31, 2014		2,382,881		$	7.39		4	$	60,652
	Exercisable at December 31, 2014		2,064,624		$	6.84		3.4	$	53,690
	Vested and expected to vest at December 31, 2014		2,374,256		$	7.37		4	$	60,465
Assumptions Used for Estimating Fair Value of Stock Options	The following table summarizes the assumptions used for estimating the fair value of stock options granted for the years ended December 31, (No options granted in 2014):
		2013			2012
	Risk-free interest rate		1.0% - 1.7%			0.8% - 1.2%
	Expected term (years)		6.08			6.08
	Expected volatility		52%			53% - 55%
	Expected dividend yield		0%			0%
	Weighted-average grant date fair value per share	$	7.71		$	4.24

Stockholders_Deficit_Tables

Stockholders' Deficit (Tables)	12 Months Ended
	Dec. 31, 2014
Shares of Common Stock Reserved for Future Issuance	At December 31, 2014, the Company had reserved a total of 5,069,853 of its authorized 50,000,000 shares of common stock for future issuance as follows:
	Outstanding stock options	2,382,881
	Restricted stock units	720,370
	Possible future issuance under stock option plans	1,966,602
	Total common shares reserved for future issuance	5,069,853

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Components of Income Tax Expense (Benefit)	The following summarizes the components of income tax expense (benefit) for the years ended December 31:
		2014			2013			2012
	Current:
	Federal	$	—		$	—		$	—
	State and local		25			(31	)		84
	Total current expense (benefit)	$	25		$	(31	)	$	84
	Deferred:
	Federal	$	—		$	—		$	—
	State and local		—			—			—
	Total deferred taxes	$	—		$	—		$	—
Reconciliation Between Effect of Applying Federal Statutory Rate and Effective Income Tax Rate Used to Calculate Income Tax Provision	Reconciliation between the effect of applying the federal statutory rate and the effective income tax rate used to calculate the Company’s income tax provision is as follows for the years ended December 31:
		2014			2013			2012
	Federal statutory rate		34	%		34	%		34	%
	Effect of:
	State income taxes, net of federal benefit		4.8	%		3.2	%		3.5	%
	Change in tax rates		0.4	%		0.4	%		2.6	%
	State tax credits		0.4	%		0.9	%		0	%
	Change in valuation allowance		(39.3	%)		(33.5	%)		(38.7	%)
	Uncertain tax positions		0	%		(0.9	%)		0	%
	Contingent consideration amortization		0	%		0	%		(0.4	%)
	Stock-based compensation		(0.2	%)		(0.9	%)		(1.2	%)
	Other permanent items		(0.1	%)		(0.4	%)		(0.4	%)
	Deferred tax true-up		0	%		(2.7	%)		0	%
	Income tax provision effective rate		0	%		0.1	%		(0.6	%)
Components of Deferred Tax Asset and Liability	The significant components of the Company’s deferred tax asset and liability were as follows as of December 31:
		2014			2013
	Deferred tax assets relating to:
	Net operating loss carryforwards	$	26,132		$	15,553
	Deferred revenue		23,612			16,779
	Commissions and incentive accrual		1,771			463
	Deferred rent		816			1,027
	State tax credits		3,195			2,961
	Stock-based compensation		1,993			1,615
	Compensation and other accruals		3,964			1,361
	Total gross deferred tax assets		61,483			39,759
	Deferred tax liabilities:
	Prepaid expenses	$	—		$	(727	)
	Property and equipment, financing obligations and intangible assets		(2,514	)		(4,610	)
	Total gross deferred tax liabilities		(2,514	)		(5,337	)
	Deferred tax assets less liabilities		58,969			34,422
	Less: valuation allowance		(58,969	)		(34,422	)
	Net deferred tax asset (liability)	$	—		$	—
Reconciliation of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amounts of unrecognized tax benefits is as follows for the year ended December 31, 2014 and 2013 (no unrecognized tax benefits in 2012):
		2014			2013
	Balance at beginning of year	$	437		$	—
	Additions based on tax positions related to the current year		—			—
	Additions for tax positions in prior years		—			437
	Reductions for tax positions of prior years		—			—
	Reductions for tax positions due to lapse of statute		—			—
	Settlements		—			—
	Balance at end of year	$	437		$	437

Segments_and_Geographic_Inform1

Segments and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2014
Segments and Geographic Information
		Year Ended December 31,
		2014		2013		2012
	Revenue from external customers by segment:
	Employer	$	62,016	$	40,656	$	23,760
	Carrier		75,404		64,096		57,979
	Total net revenue from external customers	$	137,420	$	104,752	$	81,739
	Depreciation and amortization by segment:
	Employer	$	4,392	$	3,035	$	2,337
	Carrier		5,101		5,137		6,223
	Total depreciation and amortization	$	9,493	$	8,172	$	8,560
	Gross profit by segment
	Employer	$	16,186	$	13,316	$	9,810
	Carrier		33,764		29,025		27,529
	Total gross profit by segment	$	49,950	$	42,341	$	37,339

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
Unaudited Quarterly Statements of Operations Data	The following tables set forth selected unaudited quarterly statements of operations data for each of the eight quarters in the years ended December 31, 2014 and 2013.
			Quarter Ended
			December 31,			September 30,			June 30,			March 31,			December 31,			September 30,			June 30,			March 31,
			2014 (b)			2014			2014			2014			2013			2013			2013			2013
	Consolidated Statements of Operations Data:
	Revenue		$	40,187		$	34,200		$	32,337		$	30,696		$	30,256		$	26,317		$	24,332		$	23,847
	Gross profit			16,335			10,845			11,300			11,470			10,783			10,146			10,010			11,402
	Total operating expenses			28,241			28,607			28,711			23,294			18,474			16,504			19,091			16,466
	Operating loss			(11,906	)		(17,762	)		(17,411	)		(11,824	)		(7,691	)		(6,358	)		(9,081	)		(5,064	)
	Net loss		$	(13,689	)	$	(18,888	)	$	(18,200	)	$	(12,402	)	$	(8,282	)	$	(6,836	)	$	(9,628	)	$	(5,615	)
	Net loss per common share (a)			(0.54	)		(0.74	)		(0.72	)		(0.51	)		(0.34	)		(1.08	)		(2.00	)		(1.17	)
	Weighted-average common shares outstanding— basic and diluted			25,569,203			25,503,194			25,200,093			24,541,359			24,474,566			6,320,731			4,809,518			4,798,043
	(a)	Quarterly and year-to-date computations of per share amounts are made independently. Therefore, the sum of the per-share amounts for the quarters may not agree with per share amounts for the year.
	(b)	During the fourth quarter of 2014, the Company recorded a cumulative adjustment to correct prior period errors that related to an overstatement of amortization of certain capitalized software costs. The impact of these items on the Company’s Consolidated Statement of Operations decreased cost of revenue, increased gross profit, and decreased loss from operations, loss before income taxes, and net loss by $628. The Company did not adjust the prior periods as it concluded that such adjustments were not material to the current or prior period Consolidated Financial Statements.

Organization_and_Description_o1

Organization and Description of Business - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013
Organization And Description Of Business [Line Items]
Proceeds from initial public offering, net of issuance costs	$70,064		$70,064
Underwriting discounts and commissions	5,565
Other offering expenses	$3,871
Conversion of redeemable convertible preferred units into common stock	16,496,860	16,496,860
Common stock par value	$0.00	$0.00	$0.00
IPO
Organization And Description Of Business [Line Items]
Stock issued, shares	3,000,000
Stock issued, public offering price	$26.50
Existing shareholders
Organization And Description Of Business [Line Items]
Stock issued, shares	2,675,250

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2015
	Customer	Customer
	Segment
Summary of Significant Accounting Policies [Line Items]
Number of customers exceeded 10% of total revenue	0	0
Allowance for doubtful accounts	$10	$10
Number of operating segments	2
Advertising costs	394	265	257
Capitalized Software Development Costs
Summary of Significant Accounting Policies [Line Items]
Useful lives for property and equipment	3 years
Customer Concentration Risk | Accounts Receivable | Aetna
Summary of Significant Accounting Policies [Line Items]
Concentration risk, percentage	13.30%	11.30%
Customer Concentration Risk | Revenue | Aetna
Summary of Significant Accounting Policies [Line Items]
Concentration risk, percentage			10.50%
Maximum
Summary of Significant Accounting Policies [Line Items]
Cash equivalents maturity period	3 months
Finite lived intangibles, useful life	4 years
Maximum | Subsequent Event | Customer Agreements
Summary of Significant Accounting Policies [Line Items]
Deferred revenue recognition period				10 years
Minimum
Summary of Significant Accounting Policies [Line Items]
Finite lived intangibles, useful life	1 year
Minimum | Subsequent Event | Customer Agreements
Summary of Significant Accounting Policies [Line Items]
Deferred revenue recognition period				7 years
Allowance for Returns
Summary of Significant Accounting Policies [Line Items]
Allowance for returns	$1,653	$800

Estimated_Useful_Lives_for_Sig

Estimated Useful Lives for Significant Property and Equipment (Detail)	12 Months Ended
	Dec. 31, 2014
Computers and Related Equipment | Minimum
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	3 years
Computers and Related Equipment | Maximum
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	7 years
Furniture and Fixtures
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	7 years
Other Equipment | Minimum
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	5 years
Other Equipment | Maximum
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	12 years
Purchased Software and Licenses | Minimum
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	1 year
Purchased Software and Licenses | Maximum
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	7 years
Vehicles
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	5 years
Building
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	30 years
Leasehold Improvements
Property Plant and Equipment Estimated Useful Lives [Line Items]
Useful lives for property and equipment	Lesser of estimated useful life of asset or lease term

Common_Share_Equivalents_Secur

Common Share Equivalents Securities Excluded From Calculation of Weighted Average Common Share Outstanding (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive common share equivalents	3,103,251	3,656,495	20,117,924
Series A Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive common share equivalents			14,055,851
Series B Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive common share equivalents			2,441,009
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive common share equivalents	720,370	97,700
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive common share equivalents	2,382,881	3,058,795	3,121,064
Warrant to Purchase Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive common share equivalents		500,000	500,000

Basic_and_Diluted_Net_Loss_per

Basic and Diluted Net Loss per Common Share (Detail) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Numerator:
Net loss	($13,689)	[1]	($18,888)		($18,200)		($12,402)		($8,282)		($6,836)		($9,628)		($5,615)		($63,179)	($30,361)	($14,873)
Net loss attributable to common stockholders																	($63,179)	($30,361)	($14,873)
Denominator:
Weighted-average common shares outstanding, basic and diluted	25,569,203	[1]	25,503,194		25,200,093		24,541,359		24,474,566		6,320,731		4,809,518		4,798,043		25,207,099	10,144,243	4,812,632
Net loss per common share, basic and diluted	($0.54)	[1],[2]	($0.74)	[2]	($0.72)	[2]	($0.51)	[2]	($0.34)	[2]	($1.08)	[2]	($2)	[2]	($1.17)	[2]	($2.51)	($2.99)	($3.09)
[1]	During the fourth quarter of 2014, the Company recorded a cumulative adjustment to correct prior period errors that related to an overstatement of amortization of certain capitalized software costs. The impact of these items on the Company's Consolidated Statement of Operations decreased cost of revenue, increased gross profit, and decreased loss from operations, loss before income taxes, and net loss by $628. The Company did not adjust the prior periods as it concluded that such adjustments were not material to the current or prior period Consolidated Financial Statements.
[2]	Quarterly and year-to-date computations of per share amounts are made independently. Therefore, the sum of the per-share amounts for the quarters may not agree with per share amounts for the year.

Marketable_Securities_Addition

Marketable Securities - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Gain (Loss) on Investments [Line Items]
Held-to-maturity securities, amortized cost basis	5,135	$13,168
Held-to-maturity securities, net carrying amount	5,135	13,168
Held-to-maturity securities, fair value	5,134	13,166
Held-to-maturity securities, gross unrealized holding gains	0	0
Held-to-maturity securities, gross unrealized holding losses	1	$2
Minimum
Gain (Loss) on Investments [Line Items]
Held-to-maturity securities, contractual maturity period	1 month
Maximum
Gain (Loss) on Investments [Line Items]
Held-to-maturity securities, contractual maturity period	3 months

Unrealized_Loss_Position_of_In

Unrealized Loss Position of Investments Other-Than-Temporary Impairment not Recognized in Earnings (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Gain (Loss) on Investments [Line Items]
Aggregate fair value of investments with unrealized losses	$5,135	[1]	$1,281	[1]
Aggregate amount of unrealized losses	($1)		($2)
[1]	Investments have been in a continuous loss position for less than 12 months

Assets_and_Liabilities_Measure

Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$50,695		$65,443
Money market mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	50,695	[1]	65,443	[1]
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	50,695		65,443
Level 1 | Money market mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	$50,695	[1]	$65,443	[1]
[1]	Money market funds are classified as cash equivalents in the Company's consolidated balance sheets. As short-term, highly liquid investments readily convertible to known amounts of cash, with remaining maturities of three months or less at the time of purchase, the Company's cash equivalent money market funds have carrying values that approximate fair value.

Changes_in_Level_3_Instruments

Changes in Level 3 Instruments Measured at Fair Value on a Recurring Basis (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance of contingent consideration at beginning of period	$328
Change in fair value	-43
Accretion of discount	26
Payment	($311)

Property_and_Equipment_Detail

Property and Equipment (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$99,209	$63,918
Accumulated depreciation and amortization	-45,188	-36,474
Property and equipment, net	54,021	27,444
Building
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,965	7,965
Computers and Related Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	18,871	13,954
Purchased Software and Licenses
Property, Plant and Equipment [Line Items]
Property and equipment, gross	20,392	17,556
Software Developed
Property, Plant and Equipment [Line Items]
Property and equipment, gross	18,397	16,182
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,834	2,717
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,334	1,730
Other Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,009	1,922
Vehicles
Property, Plant and Equipment [Line Items]
Property and equipment, gross	111	111
Construction in progress, build-to-suit
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$24,296	$1,781

Property_and_Equipment_Additio

Property and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$9,493	$8,172	$8,560
Fixed assets acquired under capital lease	8,569	8,463
Accumulated depreciation of assets under capital leases	1,521	2,033
Capitalized software cost gross	2,215	2,751
Amortization of capitalized software cost	2,257	2,618	3,145
Capitalized software cost net	4,134	4,101
Employer
Property, Plant and Equipment [Line Items]
Depreciation and amortization	4,392	3,035	2,337
Impairment of long lived assets			1,051
Property and Equipment
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$9,188	$7,849	$8,225

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Goodwill	$1,634,000	$1,634,000
Amortization expense related to acquisition of intangible assets	305,000	323,000	335,000
Impairment of intangible assets	$0	$0	$0

AcquisitionRelated_Intangible_

Acquisition-Related Intangible Assets (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$2,426	$2,426
Accumulated Amortization	-1,475	-1,170
Net Carrying Amount	951	1,256
Weighted- Average Remaining Useful Life (in years)	3 years 6 months	4 years 4 months 24 days
Trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	240	240
Accumulated Amortization	-212	-164
Net Carrying Amount	28	76
Weighted- Average Remaining Useful Life (in years)	7 months 6 days	1 year 7 months 6 days
Customer Agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,060	2,060
Accumulated Amortization	-1,137	-880
Net Carrying Amount	923	1,180
Weighted- Average Remaining Useful Life (in years)	3 years 7 months 6 days	4 years 7 months 6 days
Non-compete Agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	126	126
Accumulated Amortization	($126)	($126)
Weighted- Average Remaining Useful Life (in years)	0 years	0 years

Expected_Amortization_Expense_

Expected Amortization Expense for Intangible Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Estimated Amortization Expense [Line Items]
2015	$286
2016	257
2017	257
2018	151
2019	0
Net Carrying Amount	$951	$1,256

Revolving_Line_of_Credit_and_N1

Revolving Line of Credit and Notes Payable - Additional Information (Detail) (USD $)

12 Months Ended

1 Months Ended

0 Months Ended

1 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Aug. 31, 2014

Dec. 31, 2014

Jun. 30, 2014

Aug. 30, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Aug. 27, 2013

Jan. 01, 2013

Debt Instrument [Line Items]

Proceeds from notes payable borrowing

$1,465

$4,535

Proceeds from line of credit borrowing

14,000

10,757

Payments on revolving line of credit

2,100

5,000

Amount outstanding under credit facility

17,657

5,757

17,657

Amount available to borrow under line of credit

12,507

12,507

Line of credit facility interest rate

3.25%

Line of credit facility expiration date

27-Aug-16

After Amendment

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

35,000

Before Amendment

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

15,000

LIBOR

Debt Instrument [Line Items]

Line of credit facility interest rate

2.75%

Period of variable interest rate

30 days

Line of credit facility, annual commitment fee amount

70

Line of credit facility commitment fee percentage on unused facility

0.20%

Maximum | LIBOR

Debt Instrument [Line Items]

Line of credit facility basis spread on variable rate

0.50%

Hardware And Software

Debt Instrument [Line Items]

Proceeds from line of credit borrowing

7,000

7,000

Payments on revolving line of credit

2,100

Revolving Line of Credit

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

35,000

Credit Facility Notes

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

6,000

Amount outstanding under credit facility

4,535

Proceeds from notes payable borrowing

591

874

Line of credit facility Installment

Repayable in equal monthly installments of principal and interest through dates ranging from December 2015 to July 2016.

Repayable in equal monthly installments of principal and interest through dates ranging from December 2015 to July 2016.

Proceeds from line of credit borrowing

5,757

Payments on revolving line of credit

$5,000

Credit Facility Notes | Minimum

Debt Instrument [Line Items]

Fixed annual interest rates

3.60%

Credit Facility Notes | Maximum

Debt Instrument [Line Items]

Fixed annual interest rates

3.70%

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)	1 Months Ended		12 Months Ended			1 Months Ended			12 Months Ended	1 Months Ended
	Dec. 31, 2013	Aug. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 30, 2014	Nov. 30, 2013	Mar. 31, 2013	Dec. 31, 2011	Sep. 30, 2014
Commitments and Contingencies Disclosure [Line Items]
Operating lease term			15 years
Operating lease expiration date		2015-04
Operating lease renewal option term			5 years
Operating lease commencement date	2015-01
Lease yearly expenses			$4,099,000	$2,517,000	$1,946,000
Financing obligation			20,124
Total payment under capital lease			8,231,000	3,343,000	3,145,000
Capital lease agreement period	15 years
Minimum
Commitments and Contingencies Disclosure [Line Items]
Operating lease expiration year			2017
Maximum
Commitments and Contingencies Disclosure [Line Items]
Operating lease expiration year			2029
Software and Colocation Services
Commitments and Contingencies Disclosure [Line Items]
Financing obligation			5,001,000
Lease and financing arrangement
Commitments and Contingencies Disclosure [Line Items]
Financing obligation	13,097,000		31,697,000	13,097,000
Financing Obligation
Commitments and Contingencies Disclosure [Line Items]
Financing obligation			89,901,000
Data Processing Equipment and Software | April 2014 Lease Agreement
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period						3 years
Financing obligation term						3 years
Total payment under financing obligation						629,000
Financing obligation			300,000
Total payment under capital lease						3,779,000
Capital lease down payment						1,340,000
Capital lease aggregate monthly payment						2,439,000
Capital lease obligation			1,803,000
Financing obligation down payment						223,000
Financing obligation aggregate monthly payment						406,000
Data Processing Equipment and Software | November 2013 Lease Agreement
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period							3 years
Financing obligation term							3 years
Total payment under financing obligation							4,039,000
Financing obligation	3,872,000		2,287,000	3,872,000
Total payment under capital lease							4,160,000
Capital lease obligation	3,988,000		2,355,000	3,988,000
Data Processing Equipment and Software | March 2013 Lease Agreements
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period								3 years
Total payment under capital lease								1,117,000
Capital lease obligation	785,000		448,000	785,000
Data Processing Equipment and Software | 2013 and 2012 Lease Agreement
Commitments and Contingencies Disclosure [Line Items]
Capital lease obligation	216,000		135,000	216,000
Percentage of economic life that will initiate the passage of title to the Company			75.00%
Percentage of present value of minimum lease payments at beginning of lease term of fair value of leased property			90.00%
Data Processing Equipment and Software | 2013 and 2012 Lease Agreement | Minimum
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period			1 year
Data Processing Equipment and Software | 2013 and 2012 Lease Agreement | Maximum
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period			5 years
Data Processing Equipment and Software | 2011 Lease Agreement
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period									3 years
Total payment under capital lease									3,005,000
Capital lease obligation	465,000		0	465,000
Property and Equipment for Operations | Minimum
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period			12 months
Interest rate under lease agreement			3.00%
Property and Equipment for Operations | Maximum
Commitments and Contingencies Disclosure [Line Items]
Capital lease agreement period			5 years
Interest rate under lease agreement			12.40%
Call Hosting Agreement
Commitments and Contingencies Disclosure [Line Items]
Financing obligation term										1 year
Total payment under financing obligation										150,000
Financing obligation			113,000
Headquarters building, build-to-suit | Lease and financing arrangement
Commitments and Contingencies Disclosure [Line Items]
Financing obligation	9,023,000		8,873,000	9,023,000
Headquarters building, build-to-suit | Financing Obligation
Commitments and Contingencies Disclosure [Line Items]
Financing obligation			14,357,000
Construction in progress, build-to-suit | Lease and financing arrangement
Commitments and Contingencies Disclosure [Line Items]
Financing obligation	202,000		20,124,000	202,000
Construction in progress, build-to-suit | Financing Obligation
Commitments and Contingencies Disclosure [Line Items]
Financing obligation			72,754,000
Office Space Operating Leases
Commitments and Contingencies Disclosure [Line Items]
Operating lease term										5 years
Operating lease expiration date										2020-02
Number of options to extend operating lease										5
Operating lease renewal option term										1 year
Operating lease commencement date										2015-02
Lease yearly expenses										95,000
Build-to-suit Lease
Commitments and Contingencies Disclosure [Line Items]
Operating lease commencement date	2015-01
Financing obligation	81,487,000			81,487,000
Capital lease agreement period	15 years
Rentable area of leased premises	145,000
Option to extend lease term	36 months
Pro-rated termination fee if the company terminates the option			265,000
Build-to-suit Lease | Maximum
Commitments and Contingencies Disclosure [Line Items]
Annual costs prior to exercise of an option to lease space in two additional adjacent buildings	466,000
Termination fee if the company terminates an option to lease space in two additional adjacent buildings	757,000

Future_Minimum_Operating_Lease

Future Minimum Operating Lease Payments (Detail) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Leases Future Minimum Payments [Line Items]
2015	$3,857
2016	3,912
2017	3,934
2018	3,747
2019	3,841
Thereafter	20,110
Total minimum lease payments	$39,401

Financing_Obligations_Detail

Financing Obligations (Detail) (Lease and financing arrangement, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Contractual Obligation [Line Items]
Financing obligations	$31,697	$13,097
Less: current portion	-1,720	-1,702
Financing obligations, net of current portion	29,977	11,395
Headquarters building, build-to-suit
Contractual Obligation [Line Items]
Financing obligations	8,873	9,023
Software support
Contractual Obligation [Line Items]
Financing obligations	2,700	3,872
Construction in progress, build-to-suit
Contractual Obligation [Line Items]
Financing obligations	$20,124	$202

Future_Minimum_Lease_Payments_

Future Minimum Lease Payments (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Leases Future Minimum Payments [Line Items]
2015	$2,621
2016	1,998
2017	323
2018	2
2019	0
Thereafter	0
Total minimum lease payments	4,944
Less: imputed interest	-204
Less: current portion	-4,197	-4,288
Capital lease obligations, net of current portion	2,263
Financing Obligation
Leases Future Minimum Payments [Line Items]
2015	7,462
2016	7,185
2017	6,265
2018	6,407
2019	6,599
Thereafter	55,983
Total minimum lease and financing obligation payments	$89,901

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2012
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Number of common shares reserved for issuance under stock plans				5,069,853
Total compensation cost related to nonvested awards not yet recognized	$23,767
Total compensation cost related to nonvested awards not yet recognized period	3 years 4 months 24 days
Restricted stock units granted vesting period description	Restricted stock units granted to employees vest in equal annual installments generally over 4 years from the grant date.
Intrinsic value of restricted stock units expected to vest	21,746
Number of restricted stock units expected to vest	662,186
Aggregate fair value of restricted stock units vested	661
Restricted stock units vested	23,742	0	0
Aggregate intrinsic value of employee options exercised	$23,397	$6,448	$293
Stock-based compensation, option granted	0
Restricted Stock Units (RSUs)
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Stock plan vesting period	4 years
2012 Plan
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Share allocated to stock option plan	1,966,602
Stock plan vesting period	4 years
Stock plan expiration period from grant date	10 years

Number_of_Awards_Outstanding_D

Number of Awards Outstanding (Detail)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options outstanding	2,382,881	3,058,795	3,121,064
Number of restricted stock units expected to vest	720,370	97,700

StockBased_Compensation_Expens

Stock-Based Compensation Expense Related to Stock Options (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	$5,588	$1,202	$712
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	986	274	195
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	1,395	171	68
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	1,376	255	130
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	$1,831	$502	$319

Summary_of_Unvested_Restricted

Summary of Unvested Restricted Stock Units Activity (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted stock units
Restricted stock units, beginning balance	97,700
Restricted stock units, granted	679,587
Restricted stock units, Forfeited	-33,175
Restricted stock units, Vested	-23,742	0	0
Restricted stock units, ending balance	720,370	97,700
Weighted average grant date fair value
Weighted average grant date fair value, beginning balance	$48.31
Weighted average grant date fair value, granted	$37.97
Weighted average grant date fair value, Forfeited	$46.87
Weighted average grant date fair value, Vested	$48.23
Weighted average grant date fair value, ending balance	$38.63	$48.31

Summary_of_Option_Activity_Det

Summary of Option Activity (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2012
Stock options
Beginning Balance	3,058,795	3,121,064
Granted	0
Exercised	-642,152
Forfeited	-31,664
Expired	-2,098
Ending Balance	2,382,881	3,121,064
Exercisable	2,064,624
Vested and expected to vest	2,374,256
Weighted Average Exercise Price
Beginning Balance	$6.75
Granted	$0
Exercised	$4.39
Forfeited	$9.98
Expired	$1.38
Ending Balance	$7.39
Exercisable	$6.84
Vested and expected to vest	$7.37
Weighted Average Remaining Contractual Term
Outstanding	4 years
Exercisable	3 years 4 months 24 days
Vested and Expected to Vest	4 years
Aggregate Intrinsic Value
Outstanding	$60,652
Exercisable	53,690
Vested and Expected to vest	$60,465

Assumptions_Used_For_Estimatin

Assumptions Used For Estimating Fair Value of Stock Options Granted (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	1.00%	0.80%
Risk-free interest rate, maximum	1.70%	1.20%
Expected term (years)	6 years 29 days	6 years 29 days
Expected volatility, minimum		53.00%
Expected volatility, maximum		55.00%
Expected volatility	52.00%
Expected dividend yield	0.00%	0.00%
Weighted-average grant date fair value per share	$7.71	$4.24

Stockholders_Deficit_Additiona

Stockholders' Deficit - Additional Information (Detail) (USD $)	1 Months Ended		12 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009
Schedule Of Stockholders Equity [Line Items]
Conversion of redeemable convertible preferred units into common stock		16,496,860	16,496,860
Common stock, par value		$0.00	$0.00	$0.00
Preferred stock, shares authorized before amendment			21,496,860
Preferred stock, shares authorized			5,000,000	5,000,000
Common stock , authorized shares reserved for future issuance			5,069,853
Common stock , shares authorized			50,000,000	50,000,000
Warrant contract term						5 years
Number of common stock shares called by warrant right						500,000
Warrant issued, exercise price						$5.48
Warrant issued, expiration term						10 years
Warrant issued, exercise period						9 years 6 months
Issuance of common stock for cashless exercise of warrant	455,521
Accretion of customer warrant			$744	$892	$488

Common_Stock_for_Future_Issuan

Common Stock for Future Issuance (Detail)	Dec. 31, 2014
Common Stock [Line Items]
Outstanding stock options	2,382,881
Restricted stock units	720,370
Possible future issuance under stock option plans	1,966,602
Total common shares reserved for future issuance	5,069,853

Employee_Benefit_Plan_Addition

Employee Benefit Plan - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2014
Defined Contribution Plan Disclosure [Line Items]
Defined benefit plan service period of employees to be eligible to participate in 401(k) plan	1 day
Eligible age of participation in 401 (k) plan	Employees are eligible to participate in the 401(k) Plan after one day of service and upon attainment of age 21
Employers matching contribution, percent	50.00%	50.00%	50.00%
Percentage of employee vesting amount on matching company contribution	20.00%	20.00%	20.00%
Employee's service requisite period for vesting matching company contribution	2 years	2 years	2 years
Employers matching contribution	$2,083	$1,339	$1,013
Maximum
Defined Contribution Plan Disclosure [Line Items]
Employers matching contribution percent of qualifying compensation	3.00%	3.00%	3.00%
Scenario, Forecast
Defined Contribution Plan Disclosure [Line Items]
Employee's service requisite period for vesting matching company contribution				1 year

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Income Taxes [Line Items]
Deferred tax valuation allowance	$58,969,000	$34,422,000
Increase in valuation allowance	24,547,000	10,191,000
Federal and state net operating loss carryforwards	30,749,000
Excess tax benefits from deductions from exercise of nonqualified stock options	5,024,000
Gross unrecognized tax benefits	437,000	437,000	0
Portion of unrecognized tax benefits for Company's effective tax rate	0
SOUTH CAROLINA
Schedule Of Income Taxes [Line Items]
Tax credit carryovers	5,277,000	4,497,000
Corporate Headquarters
Schedule Of Income Taxes [Line Items]
Tax credit carryovers	5,277,000	4,497,000
Expiration of tax credit carryforward, beginning year	2020
Expiration of tax credit carryforward, ending year	2028
Federal
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards	68,235,000	41,374,000
Net operating loss carryforwards expiration, beginning year	2022
Net operating loss carryforwards expiration, ending year	2033
State and Local Jurisdiction
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards	$61,583,000	$33,665,000
Minimum
Schedule Of Income Taxes [Line Items]
U.S. federal income tax examination year	2007
Maximum
Schedule Of Income Taxes [Line Items]
U.S. federal income tax examination year	2013

Summary_of_Components_of_Incom

Summary of Components of Income Tax (Benefit) Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components Of Income Tax Expense Benefit [Line Items]
Federal	$0	$0	$0
State and local	25	-31	84
Total current (benefit) expense	25	-31	84
Federal	0	0	0
State and local	0	0	0
Total deferred taxes	$0	$0	$0

Reconciliation_between_Effect_

Reconciliation between Effect of Applying Federal Statutory Rate and Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Effective Tax Rate Reconciliation [Line Items]
Federal statutory rate	34.00%	34.00%	34.00%
State income taxes, net of federal benefit	4.80%	3.20%	3.50%
Change in tax rates	0.40%	0.40%	2.60%
State tax credits	0.40%	0.90%	0.00%
Change in valuation allowance	-39.30%	-33.50%	-38.70%
Uncertain tax positions	0.00%	-0.90%	0.00%
Contingent consideration amortization	0.00%	0.00%	-0.40%
Stock-based compensation	-0.20%	-0.90%	-1.20%
Other permanent items	-0.10%	-0.40%	-0.40%
Deferred tax true-up	0.00%	-2.70%	0.00%
Income tax provision effective rate	0.00%	0.10%	-0.60%

Components_of_Deferred_Tax_Ass

Components of Deferred Tax Asset and Liability (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred tax assets relating to:
Net operating loss carryforwards	$26,132	$15,553
Deferred revenue	23,612	16,779
Commissions and incentive accrual	1,771	463
Deferred rent	816	1,027
State tax credits	3,195	2,961
Stock-based compensation	1,993	1,615
Compensation and other accruals	3,964	1,361
Total gross deferred tax assets	61,483	39,759
Deferred tax liabilities
Prepaid expenses		-727
Property and equipment, financing obligations and intangible assets	-2,514	-4,610
Total gross deferred tax liabilities	-2,514	-5,337
Deferred tax assets less liabilities	58,969	34,422
Less: valuation allowance	-58,969	-34,422
Net deferred tax asset (liability)	$0	$0

Reconciliation_of_Unrecognized

Reconciliation of Unrecognized Tax Benefits (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Income Tax Contingency [Line Items]
Beginning balance	$437,000	$0
Additions based on tax positions related to the current year	0	0
Additions for tax positions of prior years		437,000
Reductions for tax positions of prior years	0	0
Reductions for tax positions due to lapse of statute	0	0
Settlements	0	0
Ending balance	$437,000	$437,000

Segment_and_Geographic_Informa

Segment and Geographic Information (Detail) (USD $)	3 Months Ended									12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net revenue from external customers	$40,187	[1]	$34,200	$32,337	$30,696	$30,256	$26,317	$24,332	$23,847	$137,420	$104,752	$81,739
Depreciation and amortization										9,493	8,172	8,560
Gross profit	16,335	[1]	10,845	11,300	11,470	10,783	10,146	10,010	11,402	49,950	42,341	37,339
Employer
Segment Reporting Information [Line Items]
Net revenue from external customers										62,016	40,656	23,760
Depreciation and amortization										4,392	3,035	2,337
Gross profit										16,186	13,316	9,810
Carrier
Segment Reporting Information [Line Items]
Net revenue from external customers										75,404	64,096	57,979
Depreciation and amortization										5,101	5,137	6,223
Gross profit										$33,764	$29,025	$27,529
[1]	During the fourth quarter of 2014, the Company recorded a cumulative adjustment to correct prior period errors that related to an overstatement of amortization of certain capitalized software costs. The impact of these items on the Company's Consolidated Statement of Operations decreased cost of revenue, increased gross profit, and decreased loss from operations, loss before income taxes, and net loss by $628. The Company did not adjust the prior periods as it concluded that such adjustments were not material to the current or prior period Consolidated Financial Statements.

Related_Parties_Additional_Inf

Related Parties - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
		Person
		Facility
Related Party Transaction [Line Items]
Financing obligations and operating lease agreement period		15 years
Financing obligation and lease renewal option term		5 years
Percentage of fixed annual rent increases		3.00%
Capital lease agreement period	15 years
Operating lease commencement date	2015-01
Financing obligation		$20,124
Number of office facilities		2
Number of stockholders and executives affiliated to leasing entity		2
Lease operating expenses		5,634,000	3,729,000	3,834,000
Due to related party	268,000	1,807,000	268,000
Transportation service from related party		438,000	345,000	125,000
Due to related party, current	25,000	44,000	25,000
Accounts Payable
Related Party Transaction [Line Items]
Due to related party	268,000	949,000	268,000
Accrued Expense
Related Party Transaction [Line Items]
Due to related party		$858,000

Unaudited_Quarterly_Statements

Unaudited Quarterly Statements of Operations Data (Detail) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Quarterly Financial Data [Line Items]
Revenue	$40,187	[1]	$34,200		$32,337		$30,696		$30,256		$26,317		$24,332		$23,847		$137,420	$104,752	$81,739
Gross profit	16,335	[1]	10,845		11,300		11,470		10,783		10,146		10,010		11,402		49,950	42,341	37,339
Total operating expenses	28,241	[1]	28,607		28,711		23,294		18,474		16,504		19,091		16,466		108,853	70,535	50,141
Operating loss	-11,906	[1]	-17,762		-17,411		-11,824		-7,691		-6,358		-9,081		-5,064		-58,903	-28,194	-12,802
Net loss	($13,689)	[1]	($18,888)		($18,200)		($12,402)		($8,282)		($6,836)		($9,628)		($5,615)		($63,179)	($30,361)	($14,873)
Net loss per common share	($0.54)	[1],[2]	($0.74)	[2]	($0.72)	[2]	($0.51)	[2]	($0.34)	[2]	($1.08)	[2]	($2)	[2]	($1.17)	[2]	($2.51)	($2.99)	($3.09)
Weighted-average common shares outstanding- basic and diluted	25,569,203	[1]	25,503,194		25,200,093		24,541,359		24,474,566		6,320,731		4,809,518		4,798,043		25,207,099	10,144,243	4,812,632
[1]	During the fourth quarter of 2014, the Company recorded a cumulative adjustment to correct prior period errors that related to an overstatement of amortization of certain capitalized software costs. The impact of these items on the Company's Consolidated Statement of Operations decreased cost of revenue, increased gross profit, and decreased loss from operations, loss before income taxes, and net loss by $628. The Company did not adjust the prior periods as it concluded that such adjustments were not material to the current or prior period Consolidated Financial Statements.
[2]	Quarterly and year-to-date computations of per share amounts are made independently. Therefore, the sum of the per-share amounts for the quarters may not agree with per share amounts for the year.

Unaudited_Quarterly_Statements1

Unaudited Quarterly Statements of Operations Data (Parenthetical) (Detail) (Adjustment, USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Adjustment
Schedule Of Quarterly Financial Data [Line Items]
Amount of error corrections and prior period adjustments	$628

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended		1 Months Ended		0 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Feb. 28, 2015	Jan. 31, 2015	Feb. 24, 2015	Dec. 31, 2009	Aug. 27, 2013
Subsequent Event [Line Items]
Restricted stock units, granted		679,587
Capital lease agreement period	15 years
Stock issued, value			$70,064
Maximum number of shares to be issued under warrant agreement							500,000
Warrant exercise price per share							$5.48
Revolving Line of Credit
Subsequent Event [Line Items]
Line of credit facility maximum borrowing capacity								35,000
Build-to-suit Lease
Subsequent Event [Line Items]
Capital lease agreement period	15 years
Scenario, Forecast | Revolving Line of Credit
Subsequent Event [Line Items]
Line of credit facility, expiration period				3 years
Line of credit facility maximum borrowing capacity				60,000
Scenario, Forecast | Maximum | Revolving Line of Credit
Subsequent Event [Line Items]
Amount under revolving line of credit available to company				60,000
Liquidity percentage				1.50%
Line of credit facility, unused capacity, commitment fee percentage				0.38%
Scenario, Forecast | Minimum | Revolving Line of Credit
Subsequent Event [Line Items]
Liquidity percentage				1.00%
Line of credit facility, unused capacity, commitment fee percentage				0.30%
Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Stock plan vesting period		4 years
Subsequent Event | Build-to-suit Lease
Subsequent Event [Line Items]
Capital lease agreement period					15 years
Subsequent Event | Build-to-suit Lease | Building
Subsequent Event [Line Items]
Construction-in-Progress					18,243
Subsequent Event | Build-to-suit Lease | Furniture and Fixtures
Subsequent Event [Line Items]
Construction-in-Progress					2,346
Subsequent Event | Build-to-suit Lease | Leasehold Improvements
Subsequent Event [Line Items]
Construction-in-Progress					2,277
Subsequent Event | Build-to-suit Lease | Computers and Related Equipment
Subsequent Event [Line Items]
Construction-in-Progress					764
Subsequent Event | Mercer LLC
Subsequent Event [Line Items]
Stock issued, shares						2,817,526
Stock issued, price per share						$26.50
Stock issued, value						74,664
Warrant term						30 months
Maximum number of shares to be issued under warrant agreement						580,813
Warrant exercise price per share						$26.50
Subsequent Event | Mercer LLC | Maximum
Subsequent Event [Line Items]
Common stock ownership percentage in Mercer Health & Benefits, LLC						75.00%
Outstanding common stock ownership percentage						5.00%
Subsequent Event | Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Restricted stock units, granted					26,050
Restricted stock units, aggregate grant date fair value					815
Stock plan vesting period					4 years

Valuation_and_Qualifying_Accou

Valuation and Qualifying Accounts (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Allowance for doubtful accounts and returns
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$810		$900		$358
Additions Charged To Expense	94		-22		98
Additions Charged Against Revenue	4,585		2,315		1,330
Deductions	-3,826		-2,383		-886
Balance at End of Period	1,663		810		900
Deferred tax asset valuation allowance
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	34,422		24,231		18,510
Additions Charged To Costs and Expenses	24,547	[1]	10,191	[1]	5,721	[1]
Balance at End of Period	$58,969		$34,422		$24,231
[1]	Increase in valuation allowance is related to the generation of net operating losses and other deferred tax assets.