LifeLock (LOCK) 10-K 19 Feb 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Feb. 14, 2014	Jun. 30, 2013
Document Information [Line Items]	'	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Trading Symbol	'LOCK	'	'
Entity Registrant Name	'LifeLock, Inc.	'	'
Entity Central Index Key	'0001383871	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	91,825,308	'
Entity Public Float	'	'	$851.50

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$123,911	$134,197
Marketable securities	48,688	'
Trade and other receivables, net	10,906	7,560
Deferred tax assets, net	13,117	'
Prepaid expenses and other current assets	6,961	5,753
Total current assets	203,583	147,510
Property and equipment, net	16,504	9,701
Goodwill	156,120	129,428
Intangible assets, net	47,213	51,242
Deferred tax assets, net – noncurrent	38,018	'
Other non-current assets	1,812	1,707
Total assets	463,250	339,588
Current liabilities:	'	'
Accounts payable	2,422	1,151
Accrued expenses and other liabilities	34,926	27,329
Deferred revenue	119,106	90,877
Total current liabilities	156,454	119,357
Other non-current liabilities	4,640	265
Total liabilities	161,094	119,622
Commitments and contingencies	'	'
Stockholders’ equity:	'	'
Common stock, $0.001 par value, 300,000,000 authorized at December 31, 2013 and December 31, 2012; 91,441,771 and 86,561,320 shares issued and outstanding at December 31, 2013 and December 31, 2012, respectively	91	87
Preferred stock, $0.001 par value, 10,000,000 shares authorized and no shares issued and outstanding at December 31, 2013 and December 31, 2012	'	'
Additional paid-in capital	469,636	439,883
Accumulated other comprehensive loss	-18	'
Accumulated deficit	-167,553	-220,004
Total stockholders’ equity	302,156	219,966
Total liabilities and stockholders’ equity	$463,250	$339,588

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Common stock par value	$0.00	$0.00
Common stock shares authorized	300,000,000	300,000,000
Common stock shares issued	91,441,771	86,561,320
Common stock shares outstanding	91,441,771	86,561,320
Preferred stock par value	$0.00	$0.00
Preferred stock shares authorized	10,000,000	10,000,000
Preferred stock shares issued	'	'
Preferred stock shares outstanding	'	'

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenue:	'	'	'
Consumer revenue	$340,121	$254,678	$193,949
Enterprise revenue	29,537	21,750	'
Total revenue	369,658	276,428	193,949
Cost of services	100,249	79,916	62,630
Gross profit	269,409	196,512	131,319
Costs and expenses:	'	'	'
Sales and marketing	162,891	122,989	91,217
Technology and development	40,947	29,543	17,749
General and administrative	44,070	24,629	17,510
Amortization of acquired intangible assets	7,909	6,258	'
Total costs and expenses	255,817	183,419	126,476
Income from operations	13,592	13,093	4,843
Other income (expense):	'	'	'
Interest expense	-353	-3,677	-231
Interest income	124	30	8
Change in fair value of warrant liabilities	'	3,117	-8,658
Change in fair value of embedded derivative	'	-2,785	'
Other	-21	-5	-5
Total other expense	-250	-3,320	-8,886
Income (loss) before provision for income taxes	13,342	9,773	-4,043
Income tax (benefit) expense	-39,109	-13,730	214
Net income (loss)	52,451	23,503	-4,257
Accretion of convertible redeemable preferred stock	'	-9,378	-18,926
Beneficial conversion feature on convertible redeemable preferred stock	'	-2,452	'
Net income allocable to convertible redeemable preferred stockholders	'	-5,504	'
Net income available (loss attributable) to common stockholders	$52,451	$6,169	($23,183)
Net income available (loss attributable) per share to common stockholders:	'	'	'
Basic	$0.59	$0.18	($1.24)
Diluted	$0.55	$0.09	($1.24)
Weighted-average common shares outstanding:	'	'	'
Basic	88,636	35,082	18,725
Diluted	95,946	62,191	18,725

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (Loss) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net income (loss)	$52,451	$23,503	($4,257)
Other comprehensive loss, net of tax	'	'	'
Unrealized loss on marketable securities	-18	'	'
Comprehensive income (loss)	$52,433	$23,503	($4,257)

Consolidated_Statements_of_Con

Consolidated Statements of Convertible Redeemable Preferred Stock and Stockholders' Equity (Deficit) (USD $)

Total

Series A Preferred Stock

Series B Preferred Stock

Series C Preferred Stock

Series D Preferred Stock

Series E Preferred Stock

Series E One Preferred Stock

Series E Two Preferred Stock

Common Stock

Paid-In Capital

Comprehensive Loss

Accumulated Deficit

In Thousands, except Share data

Balance at Dec. 31, 2010

($196,121)

$6,155

$9,661

$38,662

$71,803

'

'

'

$19

$12,354

'

($208,494)

Balance (in shares) at Dec. 31, 2010

'

6,428,571

6,850,000

5,677,571

10,094,389

'

'

'

18,541,294

'

'

'

Accretion on convertible redeemable preferred stock

-18,926

595

614

3,920

13,797

'

'

'

'

'

'

-18,926

Accumulated accretion of beneficial conversion feature

'

'

'

'

'

'

'

'

'

'

'

'

Stock option exercises (in shares)

856,207

'

'

'

'

'

'

'

856,207

'

'

'

Stock option exercises

1,752

'

'

'

'

'

'

'

'

1,752

'

'

Share-based compensation (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

Share-based compensation

3,285

'

'

'

'

'

'

'

'

3,285

'

'

Net income (loss)

-4,257

'

'

'

'

'

'

'

'

'

'

-4,257

Balance at Dec. 31, 2011

-214,267

6,750

10,275

42,582

85,600

'

'

'

19

17,391

'

-231,677

Balance (in shares) at Dec. 31, 2011

'

6,428,571

6,850,000

5,677,571

10,094,389

'

'

'

19,397,501

'

'

'

Issuance of stock, net of offering costs (in shares)

'

'

'

'

'

11,486,999

1,586,778

2,284,960

15,500,000

'

'

'

Issuance of stock, net of offering costs

125,663

'

'

'

'

85,215

11,542

16,951

16

125,647

'

'

Accretion on convertible redeemable preferred stock

-9,378

'

'

'

'

6,804

1,220

1,354

'

'

'

-9,378

Beneficial conversion feature

2,452

'

'

'

'

-2,045

'

-407

'

2,452

'

'

Accumulated accretion of beneficial conversion feature

-2,452

'

'

'

'

2,045

'

407

'

'

'

-2,452

Conversion of outstanding convertible redeemable preferred stock to common stock (in shares)

'

-6,428,571

-6,850,000

-5,677,571

-10,094,389

-11,486,999

-1,586,778

-2,284,960

51,320,437

'

'

'

Conversion of outstanding convertible redeemable preferred stock to common stock

268,293

-6,750

-10,275

-42,582

-85,600

-92,019

-12,762

-18,305

51

268,242

'

'

Stock option exercises (in shares)

306,819

'

'

'

'

'

'

'

'

'

'

'

Share-based compensation (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

Share-based compensation

6,758

'

'

'

'

'

'

'

'

6,758

'

'

Net income (loss)

23,503

'

'

'

'

'

'

'

'

'

'

23,503

Stock option and warrant exercises (in shares)

'

'

'

'

'

'

'

'

558,607

'

'

'

Stock option and warrant exercises

299

'

'

'

'

'

'

'

1

298

'

'

Common shares surrendered on net settlement of option and warrant exercises (in shares)

'

'

'

'

'

'

'

'

-215,225

'

'

'

Common shares surrendered on net settlement of option and warrant exercises

-356

'

'

'

'

'

'

'

'

-356

'

'

Conversion of outstanding warrants to purchase convertible redeemable preferred stock to warrants to purchase common stock

19,451

'

'

'

'

'

'

'

'

19,451

'

'

Balance at Dec. 31, 2012

219,966

'

'

'

'

'

'

'

87

439,883

'

-220,004

Balance (in shares) at Dec. 31, 2012

'

'

'

'

'

'

'

'

86,561,320

'

'

'

Accumulated accretion of beneficial conversion feature

'

'

'

'

'

'

'

'

'

'

'

'

Stock option exercises (in shares)

4,489,459

'

'

'

'

'

'

'

'

'

'

'

Share-based compensation (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

Share-based compensation

14,700

'

'

'

'

'

'

'

'

14,700

'

'

Net income (loss)

52,451

'

'

'

'

'

'

'

'

'

'

52,451

Stock option and warrant exercises (in shares)

'

'

'

'

'

'

'

'

4,621,091

'

'

'

Stock option and warrant exercises

14,674

'

'

'

'

'

'

'

4

14,670

'

'

Common shares surrendered on net settlement of option and warrant exercises (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

Shares purchased under ESPP

819

'

'

'

'

'

'

'

'

819

'

'

Shares purchased under ESPP (in shares)

'

'

'

'

'

'

'

'

107,074

'

'

'

Vesting of restricted stock units

'

'

'

'

'

'

'

'

136,886

'

'

'

Restricted stock units surrendered in lieu of withholding taxes (in shares)

'

'

'

'

'

'

'

'

-29,374

'

'

'

Restricted stock units surrendered in lieu of withholding taxes

-436

'

'

'

'

'

'

'

'

-436

'

'

Restricted stock issued

'

'

'

'

'

'

'

'

'

'

'

'

Restricted stock issued (in shares)

'

'

'

'

'

'

'

'

44,774

'

'

'

Other comprehensive loss

-18

'

'

'

'

'

'

'

'

'

-18

'

Balance at Dec. 31, 2013

$302,156

'

'

'

'

'

'

'

$91

$469,636

($18)

($167,553)

Balance (in shares) at Dec. 31, 2013

'

'

'

'

'

'

'

'

91,441,771

'

'

'

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating activities	'	'	'
Net income (loss)	$52,451	$23,503	($4,257)
Adjustment to reconcile net income (loss) to net cash provided by operating activities:	'	'	'
Depreciation and amortization	12,796	10,427	3,740
Write-off of deferred financing costs from early payoff of debt	'	1,443	'
Share-based compensation	14,700	6,758	3,285
Provision for doubtful accounts	231	46	-28
Accretion of marketable securities	323	'	'
Change in fair value of warrant liabilities	'	-3,117	8,658
Change in fair value of embedded derivative	'	2,785	'
Deferred income tax benefit	-39,197	-14,185	'
Other	21	5	5
Change in operating assets and liabilities:	'	'	'
Trade and other receivables	-3,127	-2,766	-1,067
Prepaid expenses and other current assets	-1,080	1,334	-901
Other non-current assets	328	-1,305	-287
Accounts payable	518	-2,945	1,677
Accrued expenses and other liabilities	6,920	5,913	542
Deferred revenue	28,115	20,782	13,440
Other non-current liabilities	4,374	-255	-463
Net cash provided by operating activities	77,373	48,423	24,344
Investing activities	'	'	'
Acquisition of businesses, net of cash acquired	-42,369	-157,430	'
Acquisition of property and equipment	-10,417	-7,498	-2,031
Purchase of marketable securities	-50,775	'	'
Sale and maturities of marketable securities	1,353	'	'
Decrease in restricted cash	'	1,748	500
Net cash used in investing activities	-102,208	-163,180	-1,531
Proceeds from:	'	'	'
Term loan	'	68,000	'
Initial public offering, net of offering costs	'	125,663	'
Issuance of convertible redeemable preferred stock, net of offering costs	'	102,165	'
Issuance of warrants	'	4,373	'
Stock based compensation plans	15,425	298	1,752
Payments for:	'	'	'
Term loan	'	-68,000	'
Revolving line of credit	'	'	-13,010
Obligations under capital lease	'	'	-154
Payments to Series E-1 convertible redeemable preferred stockholders	'	-10,719	'
Employee tax withholdings related to restricted stock units	-436	'	'
Debt issuance costs	-440	-1,676	-132
Net cash provided by (used in) financing activities	14,549	220,104	-11,544
Net increase (decrease) in cash and cash equivalents	-10,286	105,347	11,269
Cash and cash equivalents at beginning of year	134,197	28,850	17,581
Cash and cash equivalents at end of year	123,911	134,197	28,850
Cash paid during the period for:	'	'	'
Interest	267	1,836	316
Income taxes	1,121	518	94
Supplemental information for non-cash investing activities:	'	'	'
Accrued capital expenditures	1,300	127	'
Supplemental information for non-cash financing activities:	'	'	'
Convertible redeemable preferred stock issued as part of purchase price for ID Analytics	'	11,542	'
Preferred stock embedded derivative issued as part of purchase price for ID Analytics	'	$7,934	'

Corporation_Information

Corporation Information	12 Months Ended
	Dec. 31, 2013
Corporation Information	'
	1. Corporation Information
	We provide proactive identity theft protection services to our consumer subscribers, whom we refer to as our members, on an annual or monthly subscription basis. We also provide fraud and risk solutions to our enterprise customers.
	We were incorporated in Delaware on April 12, 2005 and are headquartered in Tempe, Arizona. On March 14, 2012, we acquired ID Analytics and its wholly owned subsidiary IDA Inc., each of which is incorporated in Delaware.
	In October 2012, we completed our IPO in which we issued and sold 15,500,000 shares of common stock at a public offering price of $9.00 per share. We received net proceeds of $125,663 after deducting the underwriting discount of $9,765 and other offering expenses of $4,072. Upon the closing of our IPO, all of our outstanding convertible redeemable preferred stock automatically converted into an aggregate of 51,320,437 shares of common stock.  Our common stock is listed on the New York Stock Exchange under the symbol “LOCK.”
	On December 11, 2013, we acquired mobile wallet innovator Lemon for approximately $42,369 in cash, net of cash acquired, and introduced our new LifeLock Wallet mobile application. The LifeLock Wallet mobile application allows consumers to replicate and store a digital copy of their personal wallet contents on their smart device for records backup, as well as transaction monitoring and mobile use of items such as credit, identification, ATM, insurance, and loyalty cards. The LifeLock Wallet mobile application also offers our members one-touch access to our identity theft protection services.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Summary of Significant Accounting Policies	'
	2. Summary of Significant Accounting Policies
	Basis of Presentation
	The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (U.S. GAAP).
	Basis of Consolidation
	The consolidated financial statements include our accounts and those of our wholly and indirectly owned subsidiaries. We eliminate all intercompany balances and transactions, including intercompany profits, and unrealized gains and losses in consolidation.
	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires us to make certain estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. We base our estimates on historical experience, current business factors, and various other assumptions that we believe are necessary to consider to form a basis for making judgments about the carrying values of assets and liabilities, the recorded amounts of revenue and expenses, and the disclosure of contingent assets and liabilities.
	We are subject to uncertainties such as the impact of future events; economic, environmental, and political factors; and changes in our business environment; therefore, actual results could differ from these estimates. Accordingly, the accounting estimates used in the preparation of our consolidated financial statements will change as new events occur, as more experience is acquired, as additional information is obtained, and as our operating environment changes. We make changes in estimates when circumstances warrant. We reflect such changes in estimates and refinements in estimation methodologies in reported results of operations. If material, we disclose the effects of changes in estimates in the notes to the consolidated financial statements. Significant estimates and assumptions affect the following: the allocation of the purchase price associated with acquisitions; the carrying value of long-lived assets; the amortization period of long-lived assets; the carrying value, capitalization, and amortization of software and website development costs; the carrying value of goodwill and other intangible assets; the amortization period of intangible assets; the provision for income taxes and related deferred tax accounts; certain accrued expenses; contingencies, litigation, and related legal accruals; and the value attributed to employee stock options and other stock-based awards.
	Operating Segments
	We have two operating segments, which are also our reporting units: consumer and enterprise. These operating segments are components for which separate financial information is available and for which operating results are evaluated on a regular basis by the chief operating decision maker in deciding how to allocate resources and in assessing the performance of the segments.
	In our consumer segment, we offer proactive identity theft protection services to our members on an annual or monthly subscription basis. In our enterprise segment, we offer fraud and risk solutions to our enterprise customers.
	Revenue Recognition—Consumer Segment
	We recognize revenue from our services provided in our consumer segment when it is probable that the economic benefits associated with the transactions will flow to us and the amount of revenue can be measured reliably. This is normally demonstrated when persuasive evidence of an arrangement exists, the fee is fixed or determinable, performance of service has been delivered, and collection is reasonably assured.
	We offer services to consumers primarily on an annual or monthly subscription basis that may include free trial periods. We typically bill subscription fees to our members’ credit card. We recognize revenue for subscriptions ratably from the last of cash receipt, activation of a member’s account, or expiration of free trial periods through the termination of the subscription period.
	We also provide consumer services for which the primary customer is a corporation or other entity that purchases identity theft protection services on behalf of its employees or customers. In such cases, we defer revenue for each member (employees or customers) until the member’s account has been activated. We then recognize revenue ratably over the remaining term of the individual subscription periods.
	We use an external sales force, referred to as Certified Referring Partners (“CRP”), that earn commissions for sales to individual members and corporations. Because we are primarily responsible for fulfillment of the service obligation, determine service specifications, and have latitude in establishing prices for our service agreements, we record all sales made by our CRPs as revenue and the related commissions as a sales and marketing expense.
	Revenue Recognition—Enterprise Segment
	Customer contract terms within our enterprise segment are generally monthly, and revenue is recognized when all of the following criteria are met: persuasive evidence of an arrangement exists, delivery has occurred or services have been rendered, the price is fixed or determined, and collection is reasonably assured.
	We recognize revenue from transaction-based services provided under hosted arrangements based on a negotiated fee per transaction. In some cases, we also negotiate a monthly minimum transaction fee, which may increase over the life of the contract. We bill and record transaction fees in excess of any of the monthly minimum fees as revenue in addition to the monthly minimum fees. In some instances, we receive an up-front, nonrefundable payment against which we apply the monthly minimum transaction fees. The up-front, nonrefundable payment is recorded as deferred revenue and recognized as revenue ratably over the usage period as we do not have sufficient evidence to accurately estimate a different pattern of usage. In other instances, the monthly minimum transaction fees are collected monthly, and we recognize revenue based on the negotiated monthly minimum transaction fees billed.
	We record revenue from projects where we are engaged to deliver a report at the end of the analysis upon delivery and acceptance of the report.
	Business Combinations
	We account for business acquisitions using the acquisition method of accounting and record identifiable intangible assets separate from goodwill. We record intangible assets at their fair value based on estimates as of the date of acquisition.
	We charge acquisition related costs that are not part of the consideration to general and administrative expense as they are incurred. These costs typically include transaction and integration costs, such as legal, accounting, and other professional fees.
	Goodwill
	Goodwill represents the excess of the purchase price of acquired businesses over the fair value assigned to the individual assets acquired and liabilities assumed. We do not amortize goodwill, but instead test goodwill for impairment at least annually and, if necessary, record any impairment. We evaluate goodwill for impairment in the fourth quarter of our fiscal year and whenever events and changes in circumstances indicate that it is more-likely-than-not that the fair value of a reporting unit that has goodwill is less than its carrying value.
	We may first make a qualitative assessment of whether it is more-likely-than-not that a reporting unit’s fair value is less than its carrying value to determine whether it is necessary to perform the two-step goodwill impairment test. The qualitative impairment test includes considering various factors, including macroeconomic conditions, industry and market conditions, cost factors, a sustained share price or market capitalization decrease, and any reporting unit specific events. If it is determined through the qualitative assessment that a reporting unit’s fair value is more-likely-than-not greater than its carrying value, the two-step impairment test is not required. If the qualitative assessment indicates it is more-likely-than-not that a reporting unit’s fair value is not greater than its carrying value, we must perform the two-step impairment test. We may also elect to proceed directly to the two-step impairment test without considering such qualitative factors.
	The first step in the two-step impairment test is the comparison of the fair value of a reporting unit with its carrying amount, including goodwill. We have two operating segments, a consumer segment and an enterprise segment, which are the same as our two reporting units. In accordance with the authoritative guidance over fair value measurements, we define the fair value of a reporting unit as the price that would be received to sell the unit as a whole in an orderly transaction between market participants at the measurement date. We primarily use the income approach methodology of valuation, which includes the discounted cash flow method, and the market approach methodology of valuation, which considers values of comparable businesses, to estimate the fair values of our reporting units. We do not believe that a cost approach is relevant to measuring the fair values of our reporting units.
	Significant management judgment is required when estimating the fair values of our reporting units, including the forecasting of future operating results, the discount rates and expected future growth rates that we will use in the discounted cash flow method of valuation, and the selection of comparable businesses that we will use in the market approach. If the estimated fair value of the reporting unit exceeds the carrying value assigned to that unit, goodwill is not impaired and no further analysis is required.
	If the carrying value assigned to a reporting unit exceeds its estimated fair value in the first step, then we perform the second step of the impairment test. In this step, we assign the fair value of the reporting unit calculated in step one to all of the assets and liabilities of that reporting unit, as if a market participant just acquired the reporting unit in a business combination. The excess of the fair value of the reporting unit determined in the first step of the impairment test over the total amount assigned to the assets and liabilities in the second step of the impairment test represents the implied fair value of goodwill. If the carrying value of a reporting unit’s goodwill exceeds the implied fair value of its goodwill, we would record an impairment loss equal to the difference. If there is no such excess, then all goodwill for that reporting unit is considered not to be impaired. No impairment was recorded to goodwill for the year ended December 31, 2013.
	Intangible Assets, Net
	In connection with our acquisitions of ID Analytics and Lemon, we recorded certain finite-lived intangible assets. We amortize the acquisition date fair value of these assets over the estimated useful lives of the assets.
	Per Share Data
	We compute basic earnings per share by dividing net income available (loss attributable) to common stockholders by the weighted-average number of common shares outstanding for the period. We determine net income available (loss attributable) to common stockholders by deducting the accretion on convertible redeemable preferred stock and the net income allocable to convertible redeemable preferred stock, determined under the two class method, from net income (loss). We compute diluted earnings per share giving effect to all potentially dilutive common stock equivalents, including share-based compensation, convertible redeemable preferred stock, warrants to acquire common stock, and warrants to acquire convertible redeemable preferred stock. We make adjustments to the diluted net income available (loss attributable) to common stockholders to reflect the reversal of gains on the change in the value of warrant liabilities and additional accretion on convertible redeemable preferred stock, assuming conversion of warrants to acquire convertible redeemable preferred stock at the beginning of the period. We offset these adjustments by reductions in the net income allocable to convertible redeemable preferred stockholders for those securities that were assumed to convert prior to the conversion in connection with our IPO. Those securities determined to be anti-dilutive as common stock equivalents are excluded from the calculation of diluted earnings per share; however, such securities continue to be included in the application of the two-class method to the extent applicable.
	Concentrations of Credit Risk
	In the normal course of business, we are exposed to credit risk. We believe our concentration of credit risk with respect to trade receivables is limited because of the large number of customers and customer dispersion across many different geographic and economic environments. We maintain an allowance for doubtful trade accounts receivable based upon factors surrounding the credit risk of specific clients, historical trends, and other information.
	Cash and Cash Equivalents
	Cash includes cash on hand and cash held with banks. Cash equivalents are short-term, highly liquid investments with original maturities of three months or less when acquired. Cash and cash equivalents are deposited in or managed by major financial institutions and at times exceed Federal Deposit Insurance Corporation insurance limits.
	Cash and cash equivalents also include credit card and debit card receivables. The majority of payments due from financial intermediaries for credit card and debit card transactions process within 72 hours, except for transactions occurring on a Friday, which are generally processed the following Monday. Amounts due from financial intermediaries for these transactions classified as cash and cash equivalents totaled $1,623 and $2,356 as of December 31, 2013 and 2012, respectively.
	Marketable Securities
	We hold investments in marketable securities consisting of corporate debt securities, municipal debt securities, and certificates of deposit. We determine the appropriate classification of marketable securities at the time of purchase and reevaluate such determination at each balance sheet date. As of December 31, 2013, we classified all marketable securities as current as such investments are available to fund current operations.  Based on our intentions regarding our marketable securities, all marketable securities are classified as available-for-sale and are carried at fair value with unrealized gains and losses recorded as a separate component of other comprehensive income, net of income taxes on the consolidated statements of comprehensive income (loss). Realized gains and losses and declines in fair value determined to be other-than-temporary are determined using the specific-identification method and are reflected as a component of other income (expense) in the consolidated statements of operations. We periodically review our marketable securities for other-than temporary declines in fair value and write down such marketable securities when an other-than-temporary decline has occurred. No such impairments of marketable securities have been recorded to date.
	Allowance for Doubtful Accounts
	We maintain an allowance for doubtful accounts to provide for uncollectible trade receivables. We base the allowance on historical collections, write-off experience, current economic trends, and changes in customer payment terms and other factors that may affect our ability to collect payments. As of December 31, 2013 and 2012, our allowance for doubtful accounts was $104 and $134, respectively.
	Property and Equipment
	We state property and equipment at cost, less accumulated depreciation, amortization, and any impairment in value. We assess long-lived assets, including our property and equipment, for impairment whenever events or changes in business circumstances arise that may indicate that the carrying amount of the long-lived assets may not be recoverable.
	We compute depreciation and amortization using the straight-line method over the following estimated useful lives of the assets:
	Leasehold improvements	3 years or the remaining term of the lease, whichever is shorter
	Telecommunications, network and computing equipment	3–5 years
	Computer software	3 years
	Furniture, fixtures and office equipment	3–5 years
	Debt Issuance Costs
	We defer and amortize issuance costs, underwriting fees, and related expenses incurred in connection with the issuance of debt instruments using the effective interest rate method over the terms of the instruments. We charge unamortized debt issuance costs to interest expense when the related debt is extinguished.
	Cost of Services
	Cost of services consists primarily of the direct and contract labor costs, fulfillment costs, printing and postage fees, and remediation costs to fulfill our service agreements. Cost of services also includes rent expense, facilities support, quality assurance expenses, and depreciation and amortization of long-lived assets related to the operations of our service fulfillment centers. We also include sales incentives provided to our members in cost of services.
	Technology and Development
	Technology and development expenses consist primarily of personnel costs incurred in product development, maintenance and testing of our websites, developing solutions for new services, internal information systems and infrastructure, third-party development, and other internal-use software systems. Our development costs are primarily incurred in the United States and primarily devoted to enhancing our consumer and enterprise service offerings.
	Share-Based Compensation
	We measure share-based compensation cost at fair value, net of estimated forfeitures. We determine fair value at the grant date using the Black-Scholes option pricing model with compensation cost amortized on a straight-line basis over each award’s full vesting period, except for awards with performance conditions, which we recognize using the accelerated method. Because of the lack of sufficient historical data to calculate expected term of equity awards, we use the average of the vesting term and the contractual term to estimate the expected term for service-based options granted to employees. We estimate volatility by utilizing our historical share price and the historical volatility of comparable companies with publicly available share prices. We include share-based compensation expense in cost of services, sales and marketing, technology and development, and general and administrative expenses consistent with the respective employees’ department in the consolidated statement of operations. The fair value of restricted stock units and restricted stock is based on the value of our stock on the grant date. Compensation cost for restricted stock units is amortized on a straight-line basis over each award’s full vesting period.
	Advertising Costs
	We expense advertising costs as incurred, except for direct-response advertising costs. Direct-response advertising costs include telemarketing, web-based marketing, and direct mail costs related directly to membership solicitation. Advertising expense totaled approximately $86,165, $66,049, and $54,567 for the years ended December 31, 2013, 2012, and 2011, respectively.
	Warrants for Shares of Convertible Redeemable Preferred Stock
	Prior to our IPO, certain warrants could be exercised to purchase shares of our convertible redeemable preferred stock. We accounted for these warrants as liabilities and recognized them at their fair value. We adjusted the carrying value of such warrants to fair value at each balance sheet date, with the change in the fair value being recorded as a component of other income (expense). In connection with our IPO, such warrants were converted into warrants to purchase shares of common stock.
	Income Taxes
	We account for income taxes using the asset and liability method. We recognize deferred tax assets and liabilities for the future tax benefits and consequences attributable to temporary differences between the financial reporting basis of assets and liabilities and their related tax basis. We measure deferred tax assets and liabilities using the enacted tax rates expected to be in effect in the years in which those temporary differences are expected to be recovered or settled. We report any penalties and interest related to income taxes in income tax expense. We provide a valuation allowance for deferred tax assets when it is more likely than not that the related benefits will not be realized. The determination of recording or releasing tax valuation allowances is made pursuant to an assessment performed by management regarding the likelihood that we will generate future taxable income against which benefits of our deferred tax assets may or may not be realized.  This assessment requires management to exercise significant judgment and make estimates with respect to our ability to generate revenues, gross profits, operating income, and taxable income in future periods.
We utilize a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon ultimate settlement. We consider many factors when evaluating and estimating our tax positions and tax benefits, which may require periodic adjustments and which may not accurately forecast actual outcomes.
Fair Value of Financial Instruments
The carrying values of cash and cash equivalents, restricted cash, trade and other receivables, and current liabilities approximate fair values, because of the short-term nature of these items. Prior to the conversion in connection with our IPO, we carried our convertible redeemable preferred stock warrant liability at fair value.
We determine the fair value of financial instruments using an exit price: the amount that would be received from the sale of an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. We use a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1 – observable inputs such as quoted prices in active markets; Level 2 – inputs other than the quoted prices in active markets that are observable, either directly or indirectly; and Level 3 – unobservable inputs for which there is little or no market data, which requires us to develop our own assumptions. On a recurring basis, we measure certain financial assets and liabilities at fair value, including our cash equivalents.
Recently Issued Accounting Standards
In February 2013, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2013-02, which supersedes and replaces the presentation requirements for reclassifications out of accumulated other comprehensive income in ASUs 2011-05 and 2011-12. The amendment requires that an entity must report the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income if the amount being reclassified is required under U.S. GAAP. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income in the same reporting period, an entity is required to cross-reference other disclosures required under U.S. GAAP that provide additional detail about those amounts. ASU 2013-02 was effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2012. We adopted the amended standards beginning January 1, 2013. As there were no amounts reclassified out of other comprehensive income during the years ended December 31, 2013 or 2012, there was no impact on our financial position, results of operations, or cash flows.
In March 2013, the FASB issued ASU 2013-04, which provides guidance on the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date. The update requires an entity to measure obligations resulting from joint and several liability obligations for which the total amount of the obligation within the scope of the update is fixed at the reporting date, as the sum of the amount the reporting entity agreed to pay on the basis of its arrangements among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. The update also requires an entity to disclose the nature and amount of the obligation as well as other information about those obligations. The amendments in ASU 2013-04 are effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2013 and must be applied retrospectively. We do not expect the adoption of ASU 2013-04 in the first quarter of 2014 to have a material impact on our financial position, results of operations, or cash flows.
In July 2013, the FASB issued ASU 2013-11, which requires a reporting entity to present an unrecognized tax benefit as a liability in the financial statements separate from deferred tax assets if a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available as of the reporting date to settle taxes that would result from the disallowance of the tax position or if a reporting entity does not intend to use the deferred tax asset for such purpose. The amendments in ASU 2013-11 are effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2013.  We do not expect the adoption of ASU 2013-11 to have a material impact on our consolidated financial statements.

Business_Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2013
Business Combinations	'
	3. Business Combinations
	Acquisition of ID Analytics
	In the first quarter of 2012, we acquired ID Analytics, a provider of fraud and risk solutions and a strategic technology partner of ours since 2009. The aggregate purchase price consisted of approximately $166,474 of cash paid at the closing (cash paid net of cash acquired was $157,430) and 1,586,778 shares of Series E-1 convertible redeemable preferred stock with a fair value of approximately $19,476 as of the acquisition date. We accounted for the acquisition using the acquisition method. Accordingly, we allocated the total purchase price to the tangible and identifiable intangible assets acquired and the net liabilities assumed based on their respective fair values on the acquisition date. As a result of the acquisition, we recorded goodwill in the amount of $129,428, of which $69,891 was assigned to our consumer segment and $59,537 was assigned to our enterprise segment, identifiable definite-lived intangible assets of $57,500, which was comprised of $4,000 related to trade name and trademarks, $33,000 related to technology, and $20,500 related to customer relationships, and net liabilities assumed of $978. The overall weighted-average life of the identifiable definite-lived intangible assets acquired was 7.6 years, which will be amortized over their respective useful lives. Our consolidated financial statements for the year ended December 31, 2012 include the results of operations of ID Analytics from the date of acquisition.
	Acquisition of Lemon
	On December 11, 2013, we acquired Lemon, a mobile wallet innovator. In connection with this acquisition, we launched our new LifeLock mobile application. The aggregate purchase price consisted of approximately $42,369 of cash paid at the closing (net of cash acquired of $3,315).
	Our consolidated financial statements for the year ended December 31, 2013 include the results of operations of Lemon from the date of acquisition. The total purchase consideration has been preliminarily allocated to the assets acquired and liabilities assumed at their estimated fair values as of the date of acquisition, as determined by management and, with respect to identifiable intangible assets, by management with the assistance of a valuation provided by a third-party valuation firm. The excess of the purchase price over the amounts allocated to assets acquired and liabilities assumed has been recorded as goodwill in our consumer segment.  The estimated fair values of assets acquired and liabilities assumed are considered preliminary and are based on information that was available as of the acquisition date.  Certain items, specifically the fair value of intangible assets, deferred taxes, and taxes payable may be subject to change as additional information is received and certain tax returns are filed.  Thus, the provisional measurements of fair value are subject to change.  We expect to finalize the valuation as soon as practicable, but no later than one year from the date of acquisition.
	We accounted for this acquisition using the acquisition method in accordance with Accounting Standards Codification (“ASC”) 805, Business Combinations. Accordingly, we have preliminarily allocated the purchase price of the acquired assets and liabilities based on their estimated fair values as of the acquisition date as summarized in the following table:
	Net assets assumed	$	3,184
	Deferred tax assets, net – noncurrent		11,929
	Intangible assets acquired		3,880
	Goodwill		26,691
	Total purchase price consideration	$	45,684
	The following is a description of the allocation of the purchase price to the net assets acquired:
	Cash	$	3,315
	Prepaid expenses and other current assets		128
	Total tangible assets acquired		3,443
	Accrued expenses		(145	)
	Deferred revenue		(114	)
	Total liabilities assumed		(259	)
	Net assets assumed	$	3,184
	The following were the identified intangible assets acquired at their preliminary fair value and the respective preliminary estimated periods over which such assets will be amortized:
					Weighted-
					Average
					Useful Life
		Amount			(in years)
	Trade name and trademarks	$	60			1
	Customer relationships		530			1
	Technology		3,290			7
		$	3,880
	The preliminary total weighted-average amortization period for the identifiable intangible assets acquired from Lemon is 6.0 years. We expect to recognize amortization expense over the next seven years.
	The goodwill resulting from the acquisition of Lemon is not deductible for income tax purposes. The preliminary goodwill is primarily attributable to the assembled workforce and expanded market opportunity when integrating Lemon’s mobile application with our existing identity theft protection services.
	In determining the preliminary purchase price allocation, we considered, among other factors, how a market participant would likely use the acquired assets and the historical and estimated future demand for Lemon’s services. The preliminary estimated fair value of intangible assets was based on the income approach. The income approach requires a projection of the cash flow that the asset is expected to generate in the future. The projected cash flow is discounted to its present value using a rate of return, or discount rate, which accounts for the time value of money and the degree of risk inherent in the asset. The expected future cash flow that is projected should include all of the economic benefits attributable to the asset, including the tax savings associated with the amortization of the intangible asset value over the tax life of the asset. The income approach may take the form of a “relief-from-royalty” methodology, a cost savings methodology, a “with and without” methodology, or excess earnings methodology, depending on the specific asset under consideration.
	The “relief-from-royalty” method was used to value the trade names and trademarks and technology acquired from Lemon. The “relief-from-royalty” method estimates the cost savings that accrue to the owner of an intangible asset that would otherwise be required to pay royalties or license fees on revenues earned through the use of the asset. The royalty rate used is based on an analysis of empirical, market-derived royalty rates for guideline intangible assets. Typically, revenue is projected over the expected remaining useful life of the intangible asset. The royalty rate is then applied to estimate the royalty savings. The key assumptions used in valuing the existing trade names and trademarks acquired were as follows: royalty rate of 1.5%, discount rate of 18.5%, tax rate of 39.3%, and an economic useful life of one year.  The key assumptions used in valuing the technology acquired were as follows: royalty rate of 12.75%, discount rate of 18.5%, tax rate of 39.3%, and an economic life of seven years.
	The customer relationships were valued using a form of the income approach utilizing the excess earnings method. Inherent in the excess earnings method is the recognition that, in most cases, all of the assets of the business, both tangible and intangible, contribute to the generation of the cash flow of the business and the net cash flows attributable to the subject asset must recognize the support of the other assets which contribute to the realization of the cash flows. The contributory asset charges are based on the fair value of the contributory assets and either pre-tax or after-tax cash flows are assessed charges representing “returns on” the contributory assets. A contributory asset charge for the use of the technology was assessed on pre-tax cash flows, while contributory asset charges for the use of the working capital, fixed assets, and assembled work force have been deducted from the after-tax cash flow in each year to determine the net future cash flow attributable to the relationships. This future cash flow was then discounted using an estimated required rate of return for the asset to determine the present value of the future cash flows attributable to the asset. The key assumptions used in valuing the customer relationships acquired were as follows: discount rate of 18.5%, tax rate of 39.3%, and estimated weighted-average economic life of one year.
	Acquisition related costs recognized for the year ended December 31, 2013 included transaction costs of $1,068, which we have classified primarily in general and administrative expense in our consolidated statements of operations. Transaction costs included expenses such as legal, accounting, valuation, and other professional services.
	For the year ended December 31, 2013, Lemon contributed immaterial revenue and net loss to our operating results.
	Had the acquisition of Lemon occurred on January 1, 2012, our pro forma consolidated revenue for the year ended December 31, 2013 would have been $370,409 (unaudited), and our pro forma net income for the year ended December 31, 2013 would have been $48,966 (unaudited).
	Had the acquisition of Lemon occurred on January 1, 2012, our pro forma consolidated revenue for the year ended December 31, 2012 would have been $276,623 (unaudited), and our pro forma net income for the year ended December 31, 2012 would have been $17,567 (unaudited).

Marketable_Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2013
Marketable Securities	'
	4. Marketable Securities
	The following is a summary of marketable securities designated as available-for-sale as of December 31, 2013:
				Gross		Gross
		Amortized		Unrealized		Unrealized			Estimated
		Cost		Gains		Losses			Fair Value
	Corporate bonds	$	37,399	$	1	$	(29	)	$	37,371
	Municipal bonds		10,820		2		(3	)		10,819
	Certificates of deposit		498		-		-			498
	Total marketable securities	$	48,717	$	3	$	(32	)	$	48,688
	All marketable securities are classified as current regardless of contractual maturity dates because we consider such investments to represent cash available for current operations.
	As of December 31, 2013, we did not consider any of our marketable securities to be other-than-temporarily impaired.  When evaluating our investments for other-than-temporary impairment, we review factors such as the length of time and extent to which fair value has been below its cost basis, the financial condition of the issuer, our ability and intent to hold the security and whether it is more likely than not that we will be required to sell the investment before recovery of its cost basis.
	The following is a summary of amortized cost and estimated fair value of marketable securities as of December 31, 2013, by maturity:
				Gross		Gross
		Amortized		Unrealized		Unrealized			Estimated
		Cost		Gains		Losses			Fair Value
	Due in one year or less	$	47,398	$	3	$	(32	)	$	47,369
	Due after one year		1,319		-		-			1,319
	Total marketable securities	$	48,717	$	3	$	(32	)	$	48,688
	We did not hold any marketable securities as of December 31, 2012.

Trade_and_Other_Receivables

Trade and Other Receivables	12 Months Ended
	Dec. 31, 2013
Trade and Other Receivables	'
	5. Trade and Other Receivables
	Trade and other receivables consisted of the following as of December 31:
		2013			2012
	Trade receivables	$	5,796		$	6,125
	Other receivables		5,214			1,569
	Less allowance for doubtful accounts		(104	)		(134	)
		$	10,906		$	7,560

Property_and_Equipment_Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2013
Property and Equipment, Net	'
	6. Property and Equipment, Net
	Property and equipment consisted of the following as of December 31:
		2013			2012
	Computer software	$	12,318		$	9,003
	Telecommunications, network and computing equipment		12,923			8,039
	Leasehold improvements		4,223			4,140
	Furniture, fixtures and office equipment		2,980			2,859
			32,444			24,041
	Less accumulated depreciation and amortization		(21,081	)		(17,514	)
			11,363			6,527
	Assets not yet placed in service		5,141			3,174
		$	16,504		$	9,701
	Depreciation expense on property and equipment for the years ended December 2013, 2012, and 2011 was $4,887, $4,169, and $3,740, respectively.

Other_Intangible_Assets

Other Intangible Assets	12 Months Ended
	Dec. 31, 2013
Other Intangible Assets	'
	7. Other Intangible Assets
	Our acquisition-related intangible assets are as follows:
		Gross					Net
		Carrying		Accumulated			Carrying
		Value		Amortization			Amount
	Trade name and trademarks	$	4,060	$	(1,439	)	$	2,621
	Technology		36,290		(8,485	)		27,805
	Customer relationships		21,030		(4,243	)		16,787
		$	61,380	$	(14,167	)	$	47,213
	Amortization expense for the years ended December 31, 2013, 2012, and 2011 was $7,909 and $6,258, and zero, respectively. Estimated future amortization of acquisition-related intangible asset for future periods is as follows:
	Years Ending December 31,
	2014	$	8,899
	2015		8,334
	2016		8,334
	2017		7,698
	2018		7,534
	Thereafter		6,414
		$	47,213

Accrued_Expenses_And_Other_Lia

Accrued Expenses And Other Liabilities	12 Months Ended
	Dec. 31, 2013
Accrued Expenses And Other Liabilities	'
	8. Accrued Expenses and Other Liabilities
	Accrued expenses and other liabilities consisted of the following as of December 31:
		2013		2012
	Marketing, commissions and other services	$	9,678	$	11,814
	Employee salaries, wages, and benefits		15,619		10,643
	Sales, property and income taxes		928		1,536
	Consulting, contract labor and professional fees		7,496		2,176
	Other		1,205		1,160
		$	34,926	$	27,329

Financing_Arrangements

Financing Arrangements	12 Months Ended
	Dec. 31, 2013
Financing Arrangements	'
	9. Financing Arrangements
	Credit Agreement
	On January 9, 2013, we refinanced our existing credit agreement and entered into a new credit agreement (the “Credit Agreement”) with Bank of America, N.A. as administrative agent, swing line lender and L/C issuer, Silicon Valley Bank as syndication agent, Merrill Lynch, Pierce, Fenner & Smith Incorporated as sole lead arranger and sole book manager, and the lenders from time to time party thereto. We refer to the Credit Agreement and related documents as the “Senior Credit Facility.” The Senior Credit Facility provides for an $85,000 revolving line of credit, which we can increase to $110,000 subject to the conditions set forth in the Credit Agreement. The revolving line of credit also includes a letter of credit subfacility of $10,000 and a swing line loan subfacility of $5,000. The Senior Credit Facility has a maturity date of January 9, 2018. As of December 31, 2013, we had no outstanding debt under our Senior Credit Facility.  We paid unused commitment fees of $267 for the year ended December 31, 2013, which is included in interest expense in the consolidated statements of operations.
	Borrowings under the Senior Credit Facility bear interest at a per annum rate equal to, at our option, either (a) a base rate equal to the highest of (i) the Federal Funds Rate plus 0.50%, (ii) the rate of interest in effect for such day as publicly announced from time to time by Bank of America as its “prime rate,” and (iii) the eurodollar rate for base rate loans plus 1.00%, plus an applicable rate ranging from 0.50% to 1.25%, or (b) the eurodollar rate for eurodollar rate loans plus an applicable rate ranging from 1.50% to 2.25%. The initial applicable rate is 0.50% for base rate loans and 1.50% for eurodollar rate loans, subject to adjustment from time to time based upon our achievement of a specified consolidated leverage ratio.
	In addition to paying interest on the outstanding principal under the Senior Credit Facility, we are also required to pay a commitment fee to the administrative agent at a rate per annum equal to the product of (a) an applicable rate ranging from 0.25% to 0.50% multiplied by (b) the actual daily amount by which the aggregate revolving commitments exceed the sum of (1) the outstanding amount of revolving borrowings, and (2) the outstanding amount of letter of credit obligations. The initial applicable rate is 0.25%, subject to adjustment from time to time based upon our achievement of a specified consolidated leverage ratio.
	We also will pay a letter of credit fee to the administrative agent for the account of each lender in accordance with its applicable percentage of a letter of credit for each letter of credit, which fee will be equal to the applicable rate then in effect, multiplied by the daily maximum amount available to be drawn under the letter of credit. The initial applicable rate for the letter of credit is 1.50%, subject to adjustment from time to time based upon our achievement of a specified consolidated leverage ratio.
	We have the right to prepay our borrowings under the Senior Credit Facility from time to time in whole or in part, without premium or penalty, subject to the procedures set forth in the Senior Credit Facility.
	All of our obligations under the Senior Credit Facility are unconditionally and jointly and severally guaranteed by each of our existing and future, direct or indirect, domestic subsidiaries, subject to certain exceptions. In addition, all of our obligations under the Senior Credit Facility, and the guarantees of those obligations, are secured, subject to permitted liens and certain other exceptions, by a first-priority lien on our and our subsidiaries’ tangible and intangible personal property, including a pledge of all of the capital stock of our subsidiaries.
	The Senior Credit Facility requires us to maintain certain financial covenants. In addition, the Senior Credit Facility requires us to maintain all material proprietary databases and software with a third-party escrow agent in accordance with an escrow agreement that we reaffirmed in connection with the Senior Credit Facility. The Senior Credit Facility also contains certain affirmative and negative covenants limiting, among other things, additional liens and indebtedness, investments and distributions, mergers and acquisitions, liquidations, dissolutions, sales of assets, prepayments and modification of debt instruments, transactions with affiliates, and other matters customarily restricted in such agreements. The Senior Credit Facility also contains customary events of default, including payment defaults, breaches of representations and warranties, covenant defaults, cross defaults to other contractual agreements, events of bankruptcy and insolvency, and a change of control. As of December 31, 2013, we were in compliance with all covenants.
	Prior Credit Agreement
	On February 7, 2012, we entered into a $70,000 credit agreement (“prior credit agreement”), which we amended on March 14, 2012, April 30, 2012, and May 29, 2012. The prior credit agreement consisted of a term loan of $68,000 and a revolving line of credit of $2,000. The prior credit agreement had a maturity date of February 7, 2016.
	The outstanding balance under the term loan carried an interest rate ranging from LIBOR plus 3.75% to 4.75% depending on our consolidated leverage ratio. The outstanding balance under the line of credit bore an interest rate ranging from LIBOR to LIBOR plus 0.125% depending on our consolidated leverage ratio.
	On October 12, 2012, we repaid the outstanding balance of the term loan with proceeds from our IPO. Amortization of debt issuance costs for the year ended December 31, 2012 totaled $1,760, including $1,443 of debt issuance costs written off at the date of repayment, and is included in interest expense in the accompanying consolidated statements of operations.
	The prior credit agreement contained certain covenants. The covenants included, among others, restrictions with respect to payment of cash dividends, mergers or consolidations, changes in nature of business, disposal of assets, and obtaining additional loans. The prior credit agreement also required us to comply with certain financial covenants.
	Letters of Credit
	During 2012, we cancelled three standby letters of credit and replaced them with $1,300 in letters of credit issued against the $2,000 revolving line of credit provided under the prior credit agreement. The restrictions on the cash used to fully collateralize the standby letters of credit were released in July 2012. In August 2013, a letter of credit in the amount of $1,200 was released by the counterparty in connection with the execution of the amendment to our office lease with respect to our headquarters.  As such, we had an outstanding letter of credit in the amount of $100 as of December 31, 2013.

Operating_Leases

Operating Leases	12 Months Ended
	Dec. 31, 2013
Operating Leases	'
	10. Operating Leases
	We have a number of lease agreements covering office space and certain equipment that we account for as operating leases. A majority of the lease agreements for office space have rent escalations that increase monthly rent payments over the lease terms and provide for a renewal option under negotiated terms and conditions upon expiration. We record rental expense on a straight-line basis over the base, non-cancelable lease terms. We recognize any difference between the calculated expense and amount actually paid as accrued rent. We reflect accrued rent as a current or non-current liability, depending on its expected date of reversal.
	Rent expense incurred under operating leases for the years ended December 31, 2013, 2012, and 2011 was $3,546, $2,758, and $1,764, respectively.
	Associated with operating leases, we have received tenant improvement allowances from lessors. We record the value of these improvements as fixed assets when acquired and amortize the assets over the term of the lease. We record an offsetting obligation as deferred rent and amortize it as a reduction to lease expense on a straight-line basis over the lease term.
	The following summarizes the future minimum lease payments for outstanding operating lease agreements as of December 31, 2013:
	2014	$	3,276
	2015		4,922
	2016		5,112
	2017		4,919
	2018		3,591
	Thereafter		18,743
		$	40,563

Stockholders_Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2013
Stockholders' Equity	'
	11. Stockholders’ Equity
	Common Stock
	We have authorized 300,000,000 shares of common stock, with a par value of $0.001 per share. As of December 31, 2013, we had 91,441,771 shares of common stock outstanding.
	Holders of our common stock are entitled to one vote for each share on all matters submitted to a vote of the stockholders, including the election of directors. Stockholders do not have cumulative voting rights in the election of directors. Accordingly, holders of a majority of the voting shares are able to elect all of the directors.
	We issue stock-based awards to our employees in the form of stock options, restricted stock units, and restricted stock. We also have an employee stock purchase plan.
	Convertible Redeemable Preferred Stock
	On October 9, 2012, in connection with the closing of our IPO, our Series B, C, D, and E-1 preferred shares automatically converted on a 1 for 1 basis into 24,208,738 shares of common stock; our Series A preferred shares automatically converted on a 1 for 1.03 basis into 6,617,647 shares of common stock; and our Series E and E-2 preferred shares converted on a 1 for 1.49 basis into 20,494,052 shares of our common stock.
	On March 14, 2012, we issued the following convertible redeemable preferred stock:
			Issue Date		Gross		Shares
					Amount
	Series E Convertible Redeemable Preferred Stock		March 14, 2012		$	86,843		11,486,999
	Series E-1 Convertible Redeemable Preferred Stock		14-Mar-12			11,542		1,586,778	(1)
	Series E-2 Convertible Redeemable Preferred Stock		14-Mar-12			17,275		2,284,960
	-1	All shares were issued as purchase consideration for ID Analytics.
	In conjunction with the issuance of the Series E, E-1, and E-2 convertible redeemable preferred stock, we amended our Certificate of Incorporation to delay the redemption date of the Series A, B, C, and D convertible redeemable preferred stock from November 15, 2011 to six months after the credit agreement maturity date, or six months after all obligations under the credit agreement have been repaid in full and the agreement terminated. The amendment of the term of the equity instruments was evaluated to determine whether it should be considered a modification or an extinguishment. We evaluated the fair value of the instruments immediately after the amendment, and determined that the fair value was not significantly different than the fair value immediately before the amendment. Additionally, we evaluated the qualitative aspects of the amendment. Based upon these evaluations, we determined the amendment to be a modification.
	Prior to the conversion to common stock at the closing of our IPO, the convertible redeemable preferred stock was recorded outside of equity because the redemption feature was not solely within our control. Through November 15, 2011, the original date on which the redemption provision became exercisable by the holders of convertible redeemable preferred stock, the recorded value of the Series A, B, C, and D convertible redeemable preferred stock was accreted to the full redemption amount using the effective interest method. The Series E, E-1, and E-2 convertible redeemable preferred stock were being accreted to the full redemption amount using the effective interest method, until conversion to common stock on the closing of our IPO. This increase was recorded as a preferred stock dividend.
	We evaluated each of our series of convertible preferred stock and determined that each should be considered an “equity host” and not a “debt host.” This evaluation was necessary to determine if any embedded features required bifurcation and, therefore, would be required to be accounted for separately as a derivative liability. Our analysis followed the “whole instrument approach,” which compares an individual feature against the entire preferred stock instrument that includes that feature. Our analysis was based on a consideration of the economic characteristics and risks of the preferred stock and, more specifically, evaluated all of the stated and implied substantive terms and features of such stock, including (1) whether the preferred stock included redemption features; (2) how and when any redemption features could be exercised; (3) whether the holders of preferred stock were entitled to dividends; (4) the voting rights of the preferred stock; and (5) the existence and nature of any conversion rights. As a result of our determination that each series of the preferred stock was an “equity host,” we determined that the embedded conversion options did not require bifurcation as derivative liabilities.
	We determined the adjustment to the ratio at which the Series E and E-2 convertible redeemable preferred stock would automatically convert into shares of common stock did not require bifurcation as derivative liabilities as it was clearly and closely related to the equity host instrument; however, these features represented a potential contingent beneficial conversion feature, which would be triggered in the event the conversion ratio multiplied by the fair value of the common stock at March 14, 2012 (the issuance date of the Series E and E-2 convertible redeemable preferred stock) exceeds the allocated value per share of the Series E and E-2 convertible redeemable preferred stock. As a result of the IPO price of $9.00 per share, we recognized a beneficial conversion feature related to the Series E and Series E-2 convertible redeemable preferred stock of $2,452, which was treated as a deemed dividend.
	We determined the cash settlement term of the Series E-1 convertible redeemable preferred stock required bifurcation and separate accounting as an embedded derivative. The fair value of this embedded feature was determined to be $7,934 at the issuance date of March 14, 2012, which was bifurcated from the issuance value of the Series E-1 convertible redeemable preferred stock and presented in long term liabilities. The embedded derivative was settled for $10,719 in connection with the closing of our IPO. Accordingly, we have recorded a realized loss of $2,785 with respect to the embedded derivative in the statement of operations.
	We have authorized 10,000,000 shares of preferred stock, with a par value of $0.001 per share. As of December 31, 2013 and 2012, no shares of preferred stock were issued and outstanding.
	Stock Warrants
	As of December 31, 2013, we had the following warrants to purchase common stock outstanding:
	Expiration Date		Shares				Exercise
							Price
	October 3, 2014			2,334,044					0.7
	December 19, 2014			166,666					4.5
	On October 9, 2012, warrants to purchase Series E and E-2 convertible redeemable preferred stock were terminated in connection with the closing of our IPO and we recognized a gain of $4,372 in other income (expense).

ShareBased_Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2013
Share-Based Compensation	'
	12. Share-Based Compensation
	Stock Plans
	In November 2006, we adopted the LifeLock, Inc. 2006 Incentive Compensation Plan (the “2006 Plan”). We reserved 18,426,332 shares of common stock under the 2006 Plan. The 2006 Plan provided for awards in the form of restricted shares, stock units, stock options (which could constitute incentive stock options or non-statutory stock options), and stock appreciation rights. Generally, stock options awarded under the 2006 Plan had a ten-year term and typically vested over a period of four years, with 25% of the grant vesting on the first anniversary of the date of grant and the remainder vesting monthly over the remaining vesting period.
	In October 2012, we adopted the LifeLock, Inc. 2012 Incentive Compensation Plan (the “2012 Plan”), which superseded the 2006 Plan. The total remaining shares of 4,902,708 available for issuance under the 2006 Plan were added to the number of shares reserved under the 2012 Plan, and no further awards will be granted under the 2006 Plan. In addition, we reserved an additional 4,200,000 shares of common stock under the 2012 Plan. The 2012 Plan provides for awards in the form of stock options (which may constitute incentive stock options or non-statutory stock options), stock appreciation rights, performance-based stock awards, restricted stock units, and restricted shares. Generally, stock options awarded under the 2012 Plan have a ten-year term and typically vest over a period of four years, with 25% of the grant vesting on the first anniversary of the date of grant and the remainder vesting monthly over the remaining vesting period.
	The total amount of compensation cost for stock-based payment arrangements recognized in the consolidated statements of operations related to stock options, restricted stock units, and performance stock units was $14,700, $6,758, and $3,285 for the years ended December 31, 2013, 2012, and 2011, respectively.
	As of December 31, 2013, a total of $56,250 of unrecognized compensation costs related to unvested stock options and unvested restricted stock units issued are expected to be recognized over the remaining weighted-average period of 3.2 years.
	Employee Stock Purchase Plan
	In October 2012, we adopted an employee stock purchase plan (the “ESPP”). The ESPP allows substantially all full-time and part-time employees to acquire shares of our common stock through payroll deductions over six month offering periods. The per share purchase price is equal to the lesser of 85% of the fair market value of a share of our common stock on the grant date or 85% of the fair market value of a share of our common stock on the last day of the offering period. Purchases are limited to 15% of an employee’s salary, up to a maximum of $25,000 of stock value per calendar year. We are authorized to grant up to 2,000,000 shares of our common stock under the ESPP. As of December 31, 2013, 107,074 shares of common stock had been issued under the ESPP. We recognized expense with respect to the ESPP of $338 and $76 for the years ended December 31, 2013 and 2012, respectively.
	Stock Options
	The following table summarizes information on the activity of stock options, including performance-based options, under the 2006 and 2012 Plans for the years ended December 31:
		2013							2012						2011
		Shares			Weighted				Shares			Weighted			Shares			Weighted
					Average							Average						Average
					Exercise							Exercise						Exercise
					Price Per							Price Per						Price Per
					Share							Share						Share
	Outstanding at beginning of year		12,273,815		$	4.24				8,660,771		$	3.07			9,053,803		$	2.88
	Granted		5,494,969			11.57				5,127,486			6.19			1,477,013			4.26
	Exercised		(4,489,459	)		3.27				(306,819	)		2.39			(856,207	)		2.05
	Expired		(33,951	)		3.22				(357,482	)		3.7			(466,852	)		4.41
	Forfeited		(1,861,123	)		7.4				(850,141	)		4.91			(546,986	)		3.61
	Outstanding at end of year		11,384,251		$	7.62				12,273,815		$	4.22			8,660,771		$	3.07
	Exercisable at end of year		4,235,609		$	4.39				6,379,166		$	2.98			5,113,662		$	2.78
	The following table summarizes additional information about stock options, including performance-based options, outstanding and exercisable as of December 31, 2013:
		Options Outstanding										Options Exercisable
	Range of	Shares Under			Weighted-			Weighted-				Shares Under		Weighted-
	Exercise Prices	Option			Average			Average				Option		Average
					Remaining			Exercise Price						Exercise Price
					Contractual			Per Share						Per Share
					Life
	$0.01 - $3.50		2,243,070			4.96		$	2.43				2,137,953	$	2.43
	$3.51 - $7.00		3,250,734			7.54			4.85				1,401,826		4.62
	$7.01 - $10.50		2,055,167			8.83			9.21				344,271		8.78
	$10.51 - $14.00		3,264,580			9.34			11.38				351,559		11.08
	$14.01 - $17.50		570,700			9.84			15.55				-		-
			11,384,251										4,235,609
	The weighted-average fair value of our outstanding stock options was $5.88, $2.57, and $1.29, for the years ended December 31, 2013, 2012, and 2011, respectively. Such amounts were estimated using the Black-Scholes option pricing model with the following weighted-average assumptions at December 31:
		2013				2012				2011
	Expected volatility		106.1	%			94.6	%			60	%
	Expected dividend yield		0	%			0	%			0	%
	Risk-free interest rate		1.3	%			1.2	%			2	%
	Expected term (years)	6.05				6.15				6.11
	We derived the risk-free interest rate assumption from the U.S. Treasury’s rates for U.S. Treasury zero-coupon bonds with maturities similar to those of the expected term of the awards being valued. We based the assumed dividend yield on our expectation of not paying dividends in the foreseeable future. We estimated forfeitures at the time of grant and revised this estimate, if necessary, in subsequent periods if actual forfeitures differed from those estimates.
	The weighted-average fair value of the options granted in the years ended December 31, 2013, 2012, and 2011 was $9.48, $4.74, and $2.43, respectively. The total intrinsic value of options exercised in 2013, 2012, and 2011 was $41,793, $1,472, and $2,230, respectively. As of December 31, 2013, the total intrinsic value of outstanding and exercisable stock options was $99,204 and $50,916, respectively.
	Restricted Stock Units
	The following table summarizes unvested restricted stock units activity under the 2012 Plan for the years ended December 31, 2012, and 2013:
		Restricted			Weighted -
		Stock Units			Average Grant
					Date Fair
					Value (per
					share)
	Unvested at December 31, 2011		-		$	-
	Granted		276,250			9
	Vested		(8,750	)		9
	Forfeited		-			-
	Unvested at December 31, 2012		267,500		$	9
	Granted		438,879			13.9
	Vested		(128,136	)		9.34
	Forfeited		-			-
	Unvested at December 31, 2013		578,243		$	12.65
	There were no restricted stock units granted prior to the year ended December 31, 2012.

Employee_Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2013
Employee Benefits	'
	13. Employee Benefits
	In 2008, we initiated a 401(k) retirement plan, which is a defined contribution retirement plan, for eligible employees. Employees are eligible to participate on the first day of service. Under the terms of the plan, employees are entitled to contribute from 1% to 100% of their total compensation, within limitations established by the Internal Revenue Code. We match 100% of the first 6% of each employee’s contribution and may also contribute additional amounts at our discretion, all subject to immediate vesting. The cost of employer contributions to the plan was $2,488, $1,908, and $1,624, for the years ended December 31, 2013, 2012, and 2011, respectively.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2013
Fair Value Measurements	'
	14. Fair Value Measurements
	As of December 31, 2013 and December 31, 2012, the fair value of our financial assets was as follows:
			Level 1		Level 2		Level 3		Total
	31-Dec-13
	Assets:
	Commercial paper (1)		$	-	$	45,110	$	-	$	45,110
	Money market funds (1)			911		-		-		911
	Corporate bonds (2)			-		37,371		-		37,371
	Municipal bonds (2)			-		10,819		-		10,819
	Certificates of deposit (2)			-		498		-		498
	Total assets measured at fair value		$	911	$	93,798	$	-	$	94,709
	31-Dec-12
	Assets:
	Commercial paper (1)		$	-	$	35,023	$	-	$	35,023
	Total assets measured at fair value		$	-	$	35,023	$	-	$	35,023
	·	Classified in cash and cash equivalents
	·	Classified in marketable securities

Net_Income_Loss_Per_Share

Net Income (Loss) Per Share	12 Months Ended
	Dec. 31, 2013
Net Income (Loss) Per Share	'
	15. Net Income (Loss) Per Share
	We compute basic net loss per share by dividing net loss less accretion on convertible redeemable preferred stock by the weighted-average number of common shares outstanding for the period. We compute diluted net loss per share giving effect to all potential dilutive common stock, including employee stock options, convertible redeemable preferred stock, warrants to acquire common stock, and warrants to acquire convertible redeemable preferred stock.
	The following table sets forth the computation of basic and diluted net income available (loss attributable) per share attributable to common stockholders for the years ended December 31:
		2013		2012			2011
	Net income (loss)	$	52,451	$	23,503		$	(4,257	)
	Less:
	Accretion of convertible redeemable preferred
	stock redemption premium		-		(9,378	)		(18,926	)
	Beneficial conversion feature on convertible
	redeemable preferred stock		-		(2,452	)		-
	Net income allocable to convertible redeemable
	preferred stockholders		-		(5,504	)		-
	Net income available (loss attributable) to common
	stockholders		52,451		6,169			(23,183	)
	Less:
	Change in fair value of warrant liabilities		-		(4,382	)		-
	Accretion of convertible redeemable preferred
	stock redemption premium for shares assumed
	issued in exercise of warrants		-		(898	)		-
	Plus:
	Net income allocable to convertible redeemable
	preferred stockholders		-		4,444			-
	Diluted net income available (loss attributable)
	to common stockholders	$	52,451	$	5,333		$	(23,183	)
	Denominator (basic):
	Weighted average common shares outstanding		88,635,832		35,081,863			18,725,305
	Denominator (diluted):
	Weighted average common shares outstanding		88,635,832		35,081,863			18,725,305
	Dilutive stock options and awards outstanding		4,991,320		4,088,101			-
	Weighted average common shares from
	preferred stock		-		22,528,878			-
	Weighted average common shares from warrants		2,318,422		491,860			-
	Net weighted average common shares outstanding		95,945,574		62,190,702			18,725,305
	Net income available (loss attributable) per share to
	common stockholders:
	Basic	$	0.59	$	0.18		$	(1.24	)
	Diluted	$	0.55	$	0.09		$	(1.24	)
	In 2013, 2012, and 2011, potentially dilutive securities were not included in the calculation of diluted loss per share, as their impact would be anti-dilutive.
	The following weighted-average number of outstanding employee stock options, restricted stock units, warrants to purchase common and convertible redeemable preferred stock, and convertible redeemable preferred stock were excluded from the computation of diluted net loss per share for the years ended December 31:
		2013		2012			2011
	Stock options outstanding		4,315,153		-			2,551,074
	Restricted stock units		45,673		-			-
	Common equivalent shares from stock warrants		-		3,585,996			2,727,702
	Common shares from convertible redeemable
	preferred stock		-		8,770,427			29,239,607
			4,360,826		12,356,423			34,518,383

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Taxes	'
	16. Income Taxes
	We have deferred tax assets and liabilities that reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. In assessing the realizability of deferred tax assets, we consider whether it is more likely than not that some portion or all of the deferred tax assets will be realized.  For the year ended December 31, 2012, we recorded a valuation allowance on our net deferred tax asset as prior to 2012, we had recorded operating losses.  As a result of operating income generated in 2012 and 2013, management has concluded that our deferred tax assets with the exception of certain state net operating losses that are set to expire in 2014 and 2015 will be realized. Realization of our deferred tax assets, net of liabilities, depends upon the achievement of projected future taxable income.  As a result of the 2013 operating income and our change in judgment regarding the realization of our deferred tax assets, our valuation allowance decreased approximately $47,917 in the year ended December 31, 2013. During the years ended December 31, 2012 and 2011, our valuation allowance decreased $12,418 and $974, respectively.   The decrease in the valuation allowance during 2012 was principally attributable to the generation of operating profits and net deferred tax liabilities established in connection with the acquisition of ID Analytics.
	The components of income tax provision were as follows at December 31:
		2013			2012			2011
	Current:
	U.S. federal	$	30		$	388		$	36
	U.S. state and local taxes		58			67			178
	Total current		88			455			214
	Deferred:
	U.S. federal		(36,631	)		(11,877	)		-
	U.S. state and local taxes		(2,503	)		(2,308	)		-
	Foreign		(63	)
	Total deferred		(39,197	)		(14,185	)		-
	Total income tax (benefit) expense	$	(39,109	)	$	(13,730	)	$	214
	A reconciliation of income tax computed at the U.S. statutory rate to the effective income tax rate is as follows at December 31:
			2013			2012			2011
	Statutory federal income tax rate		35	%		35	%		34	%
	State tax expense, net of federal benefit		3.8	%		6.1	%		-4.5	%
	Nondeductible expense related to stock warrants		0	%		-11.2	%		-72.8	%
	Nondeductible expense related to embedded derivative		0	%		10	%		0	%
	Other nondeductible expenses		6.2	%		2.7	%		-2.5	%
	Effect of change in income tax rates		-2.4	%		14.4	%		5.1	%
	Impact of state net operating losses		7	%		-11.4	%		15.5	%
	Stock options		0.1	%		0.7	%		-4.8	%
	Other		0	%		1	%		0.6	%
	Expired net operating losses		16.3	%		0	%		0	%
	Reduction in valuation allowance due to business
	combination		0	%		-145.1	%		0	%
	Change in valuation allowance		-359.1	%		-42.7	%		24.1	%
	Total expense		-293.1	%		-140.5	%		-5.3	%
	The following is a summary of the components of our deferred tax assets and liabilities at December 31:
			2013			2012
	Deferred tax assets:
	Net operating losses and credit carryforwards	$	62,570		$	62,307
	Stock options		6,580			5,513
	Deferred rent		1,692			196
	Deferred revenue		13			44
	Accrued expenses		795			1,310
	Other		118			-
	Total deferred tax assets		71,768			69,370
	Valuation allowance		(1,229	)		(49,146	)
	Net deferred tax assets	$	70,539		$	20,224
	Deferred tax liabilities:
	Property and equipment	$	(18,777	)	$	(20,012	)
	Other		(627	)		(212	)
	Total deferred tax liabilities		(19,404	)		(20,224	)
	Net deferred tax assets	$	51,135		$	-
	We estimate that U.S. federal and state net operating losses (“NOLs”) available to be carried forward approximated $199,408 and $147,321, respectively, as of December 31, 2013. The U.S. federal NOLs expire in the years 2024 through 2033. The majority of the state NOLs will expire between 2014 and 2033. Our ability to utilize our U.S. federal and state NOLs may be limited if we experience an ownership change as defined by Section 382 of the Internal Revenue Code. When a company undergoes such an ownership change, Section 382 limits the future use of NOLs generated before the change in ownership and certain subsequently recognized “built-in” losses and deductions, if any, existing as of the date of the ownership change. A company’s ability to utilize new NOLs arising after the ownership change is not affected. In 2012, we completed an analysis of prior year ownership changes, including whether there were any limitations on the use of NOLs acquired in connection with our acquisition of ID Analytics, we determined that our NOLs as well as the NOLs of ID Analytics were subject to annual limitations under Section 382. However, we determined that none of the NOL carryforwards will expire solely as a result of Section 382 limitations. In 2013, in connection with the acquisition of Lemon, we completed an analysis of Lemon’s prior ownership changes, including the change which arose as a result of our acquisition of Lemon.  As a result of the analysis, we determined that none of Lemon’s NOL carryforwards will expire as a result of 382 limitations.  Inherent in this analysis is the risk that some of Lemon’s 5%or greater shareholders had their own ownership changes, which may impact the results of our analysis.  We have made inquiries to these parties as required by the regulations and have received no responses.  If adverse information is discovered in the future, we will treat this as new information and reflect the impact in that period.  As of December 31, 2013, we had $451 of federal alternative minimum tax credit carryover which does not expire.
	As of December 31, 2013 and 2012, we have $14,821 and $1,845, respectively, of unrealized excess tax benefits from stock option exercises which have been removed from our net operating loss deferred tax asset.  When realized upon utilization or our net operating losses, the excess tax benefits will result in a credit to additional paid in capital.
	We are subject to taxation in the U.S. and various states. All of our tax years are still subject to U.S. federal, state, and local tax authorities due to our net operating loss, which started in 2006. As of December 31, 2013 and 2012, our unrecognized tax benefits were $393. We had no unrecognized tax benefits as of December 31, 2011. If recognized, the entire amount of unrecognized tax benefit would impact the effective rate.  There are no positions for which it is reasonably possible that the uncertain tax benefit will significantly increase or decrease within twelve months. As of December 31, 2013, there was no accrued interest or penalties recorded in the consolidated financial statements.
	On September 13, 2013, U.S. Treasury and the Internal Revenue Service issued final regulations regarding the deduction and capitalization of expenditures related to tangible property. The final regulations under Internal Revenue Code Sections 162, 167 and 263(a) apply to amounts paid to acquire, produce, or improve tangible property as well as dispositions of such property and are generally effective for tax years beginning on or after January 1, 2014.  We have evaluated these regulations and determined they will not have a material impact on our consolidated results of operations, cash flows, or financial position.

Segment_Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2013
Segment Reporting	'
	17. Segment Reporting
	Following our acquisition of ID Analytics in the first quarter of 2012, we began operating our business and reviewing and assessing our operating performance using two reportable segments: our consumer segment and our enterprise segment. In our consumer segment, we offer proactive identity theft protection services to consumers on an annual or monthly subscription basis. In our enterprise segment, we offer fraud and risk solutions to our enterprise customers.
	Financial information about our segments for the year ended December 31, 2013 and as of December 31, 2013 was as follows:
		Consumer		Enterprise			Eliminations			Total
	Revenue
	External customers	$	340,121	$	29,537		$	-		$	369,658
	Intersegment revenue		-		5,316			(5,316	)		-
	Income (loss) from operations		23,997		(10,405	)		-			13,592
	Goodwill		96,583		59,537			-			156,120
	Total assets		349,394		114,337			(481	)		463,250
	Financial information about our segments for the year ended December 31, 2012 and as of December 31, 2012 was as follows:
		Consumer		Enterprise			Eliminations			Total
	Revenue
	External customers	$	254,678	$	21,750		$	-		$	276,428
	Intersegment revenue		-		3,506			(3,506	)		-
	Income (loss) from operations		18,840		(5,747	)		-			13,093
	Goodwill		69,891		59,537			-			129,428
	Total assets		213,564		129,245			(3,221	)		339,588
	We allocated goodwill between our segments by estimating the expected synergies to each segment.
	We derive all of our revenue from sales in the United States, and substantially all of our long-lived assets are located in the United States.

Contingencies

Contingencies	12 Months Ended
	Dec. 31, 2013
Contingencies	'
	18. Contingencies
	As part of our consumer services, we offer 24x7x365 member service support. If a member’s identity has been compromised, our member service team and remediation specialists will assist the member until the issue has been resolved. This includes our $1 million service guarantee, which is backed by an identity theft insurance policy, under which we will spend up to $1 million to cover certain third-party costs and expenses incurred in connection with the remediation, such as legal and investigatory fees. This insurance also covers certain out-of-pocket expenses, such as loss of income, replacement of fraudulent withdrawals, and costs associated with child and elderly care, travel, and replacement of documents. While we have reimbursed members for claims under this guarantee, the amounts in aggregate for the years ended December 31, 2013, 2012, and 2011 were not material.
	In January 2010, Neal Duncan, a former stockholder, filed a breach of contract claim against us in the Superior Court of Maricopa County, Arizona. In his complaint, Mr. Duncan alleged that we breached a purported contract with him and sought an ownership interest in our company equal to 7.5%. In April 2012, the judge granted our motion for summary judgment and dismissed Mr. Duncan's lawsuit. Mr. Duncan has exhausted his avenues of appeal with the Arizona Court of Appeals and the Arizona Supreme Court. As part of our efforts to recover the attorneys’ fees and costs that we were awarded, we acquired 835 shares of our common stock held by Mr. Duncan pursuant to a garnishment proceeding.
	In September 2012, Denise Richardson filed a complaint against our company and Todd Davis. Ms. Richardson claims that she was improperly classified as an independent contractor instead of an employee and that we breached the terms of an alleged employment agreement. Ms. Richardson claims she is entitled to equitable relief, compensatory damages, liquidated damages, statutory penalties, punitive damages, interest, costs, and attorneys’ fees. The parties are awaiting the court’s decision with respect to our motion to dismiss.
	We are subject to other legal proceedings and claims that have arisen in the ordinary course of business. Although there can be no assurance as to the ultimate disposition of these matters and the proceedings disclosed above, we believe, based upon the information available at this time, that a material adverse outcome related to the matters is neither probable nor estimable.

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2013
Selected Quarterly Financial Data (unaudited)	'
	19.  Selected Quarterly Financial Data (unaudited)
	The following table sets forth certain unaudited quarterly results of operations of the Company for the years ended December 31, 2013 and 2012.  In the opinion of management, this information has been prepared on the same basis as the audited consolidated financial statements and all necessary adjustments, consisting only of normal recurring adjustments, have been included in the amounts below for a fair statement of the quarterly information when read in conjunction with the audited consolidated financial statements and related notes included elsewhere in this Annual Report on Form 10-K:
		Three Months Ended
		Dec 31,		Sep 30,		Jun 30,			Mar 31,			Dec 31,		Sep 30,			Jun 30,			Mar 31,
		2013		2013		2013			2013			2012		2012			2012			2012
		(in thousands, except per share data)
	Revenue:
	Consumer revenue	$	94,068	$	88,386	$	82,574		$	75,094		$	70,775	$	65,579		$	61,616		$	56,708
	Enterprise revenue		8,237		7,353		6,946			7,001			8,041		6,538			6,267			904
	Total revenue		102,305		95,739		89,520			82,095			78,816		72,117			67,883			57,612
	Gross profit	$	76,021		70,804		64,293			58,291			56,627		52,355			48,758			38,772
	Income (loss) from operations	$	14,041		5,658		(2,191	)		(3,916	)		5,700		6,223			1,379			(209	)
	Net income (loss)	$	53,206	$	5,427	$	(2,065	)	$	(4,117	)	$	4,080	$	7,868		$	(6,898	)	$	18,453
	Basic net income (loss) per share	$	0.58	$	0.06	$	(0.02	)	$	(0.05	)	$	0.01	$	0.06		$	(0.56	)	$	0.34
	Diluted net income (loss) per share	$	0.54	$	0.06	$	(0.02	)	$	(0.05	)	$	0.01	$	(0.16	)	$	(0.59	)	$	0.22

Valuation_And_Qualifying_Accou

Valuation And Qualifying Accounts	12 Months Ended
	Dec. 31, 2013
Valuation And Qualifying Accounts	'
	SCHEDULE II – VALUATION AND QUALIFYING ACCOUNTS
	Year ended December 31,		Beginning		Additions (recoveries) –			Deductions			Ending
			Balance		charged to						Balance
					costs and expenses
	Allowance for doubtful accounts (1)
	2013		$	134	$	114		$	(144	)	$	104
	2012			88		79			(33	)		134
	2011			115		(27	)		—			88
	Deferred tax asset valuation allowance(2)
	2013		$	49,146		(47,917	)		—		$	1,229
	2012			61,564		(12,418	)		—			49,146
	2011			62,538		(974	)		—			61,564
	-1	We record additions to the allowance for doubtful accounts based on historical collections, write-off experience, current economic trends, and changes in customer payment terms and other factors that may affect our ability to collect payments. Deductions principally reflect amounts charged off as uncollectible, less amounts recovered.
	-2	Deferred tax assets are reduced by a valuation allowance when, in our opinion, it is more likely than not that the related benefit will not be realized.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Basis of Presentation	'
	Basis of Presentation
	The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (U.S. GAAP).
Basis of Consolidation	'
	Basis of Consolidation
	The consolidated financial statements include our accounts and those of our wholly and indirectly owned subsidiaries. We eliminate all intercompany balances and transactions, including intercompany profits, and unrealized gains and losses in consolidation.
Use of Estimates	'
	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires us to make certain estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. We base our estimates on historical experience, current business factors, and various other assumptions that we believe are necessary to consider to form a basis for making judgments about the carrying values of assets and liabilities, the recorded amounts of revenue and expenses, and the disclosure of contingent assets and liabilities.
	We are subject to uncertainties such as the impact of future events; economic, environmental, and political factors; and changes in our business environment; therefore, actual results could differ from these estimates. Accordingly, the accounting estimates used in the preparation of our consolidated financial statements will change as new events occur, as more experience is acquired, as additional information is obtained, and as our operating environment changes. We make changes in estimates when circumstances warrant. We reflect such changes in estimates and refinements in estimation methodologies in reported results of operations. If material, we disclose the effects of changes in estimates in the notes to the consolidated financial statements. Significant estimates and assumptions affect the following: the allocation of the purchase price associated with acquisitions; the carrying value of long-lived assets; the amortization period of long-lived assets; the carrying value, capitalization, and amortization of software and website development costs; the carrying value of goodwill and other intangible assets; the amortization period of intangible assets; the provision for income taxes and related deferred tax accounts; certain accrued expenses; contingencies, litigation, and related legal accruals; and the value attributed to employee stock options and other stock-based awards.
Operating Segments	'
	Operating Segments
	We have two operating segments, which are also our reporting units: consumer and enterprise. These operating segments are components for which separate financial information is available and for which operating results are evaluated on a regular basis by the chief operating decision maker in deciding how to allocate resources and in assessing the performance of the segments.
	In our consumer segment, we offer proactive identity theft protection services to our members on an annual or monthly subscription basis. In our enterprise segment, we offer fraud and risk solutions to our enterprise customers.
Business Combinations	'
	Business Combinations
	We account for business acquisitions using the acquisition method of accounting and record identifiable intangible assets separate from goodwill. We record intangible assets at their fair value based on estimates as of the date of acquisition.
	We charge acquisition related costs that are not part of the consideration to general and administrative expense as they are incurred. These costs typically include transaction and integration costs, such as legal, accounting, and other professional fees.
Goodwill	'
	Goodwill
	Goodwill represents the excess of the purchase price of acquired businesses over the fair value assigned to the individual assets acquired and liabilities assumed. We do not amortize goodwill, but instead test goodwill for impairment at least annually and, if necessary, record any impairment. We evaluate goodwill for impairment in the fourth quarter of our fiscal year and whenever events and changes in circumstances indicate that it is more-likely-than-not that the fair value of a reporting unit that has goodwill is less than its carrying value.
	We may first make a qualitative assessment of whether it is more-likely-than-not that a reporting unit’s fair value is less than its carrying value to determine whether it is necessary to perform the two-step goodwill impairment test. The qualitative impairment test includes considering various factors, including macroeconomic conditions, industry and market conditions, cost factors, a sustained share price or market capitalization decrease, and any reporting unit specific events. If it is determined through the qualitative assessment that a reporting unit’s fair value is more-likely-than-not greater than its carrying value, the two-step impairment test is not required. If the qualitative assessment indicates it is more-likely-than-not that a reporting unit’s fair value is not greater than its carrying value, we must perform the two-step impairment test. We may also elect to proceed directly to the two-step impairment test without considering such qualitative factors.
	The first step in the two-step impairment test is the comparison of the fair value of a reporting unit with its carrying amount, including goodwill. We have two operating segments, a consumer segment and an enterprise segment, which are the same as our two reporting units. In accordance with the authoritative guidance over fair value measurements, we define the fair value of a reporting unit as the price that would be received to sell the unit as a whole in an orderly transaction between market participants at the measurement date. We primarily use the income approach methodology of valuation, which includes the discounted cash flow method, and the market approach methodology of valuation, which considers values of comparable businesses, to estimate the fair values of our reporting units. We do not believe that a cost approach is relevant to measuring the fair values of our reporting units.
	Significant management judgment is required when estimating the fair values of our reporting units, including the forecasting of future operating results, the discount rates and expected future growth rates that we will use in the discounted cash flow method of valuation, and the selection of comparable businesses that we will use in the market approach. If the estimated fair value of the reporting unit exceeds the carrying value assigned to that unit, goodwill is not impaired and no further analysis is required.
	If the carrying value assigned to a reporting unit exceeds its estimated fair value in the first step, then we perform the second step of the impairment test. In this step, we assign the fair value of the reporting unit calculated in step one to all of the assets and liabilities of that reporting unit, as if a market participant just acquired the reporting unit in a business combination. The excess of the fair value of the reporting unit determined in the first step of the impairment test over the total amount assigned to the assets and liabilities in the second step of the impairment test represents the implied fair value of goodwill. If the carrying value of a reporting unit’s goodwill exceeds the implied fair value of its goodwill, we would record an impairment loss equal to the difference. If there is no such excess, then all goodwill for that reporting unit is considered not to be impaired. No impairment was recorded to goodwill for the year ended December 31, 2013.
Intangible Assets, Net	'
	Intangible Assets, Net
	In connection with our acquisitions of ID Analytics and Lemon, we recorded certain finite-lived intangible assets. We amortize the acquisition date fair value of these assets over the estimated useful lives of the assets.
Per Share Data	'
	Per Share Data
	We compute basic earnings per share by dividing net income available (loss attributable) to common stockholders by the weighted-average number of common shares outstanding for the period. We determine net income available (loss attributable) to common stockholders by deducting the accretion on convertible redeemable preferred stock and the net income allocable to convertible redeemable preferred stock, determined under the two class method, from net income (loss). We compute diluted earnings per share giving effect to all potentially dilutive common stock equivalents, including share-based compensation, convertible redeemable preferred stock, warrants to acquire common stock, and warrants to acquire convertible redeemable preferred stock. We make adjustments to the diluted net income available (loss attributable) to common stockholders to reflect the reversal of gains on the change in the value of warrant liabilities and additional accretion on convertible redeemable preferred stock, assuming conversion of warrants to acquire convertible redeemable preferred stock at the beginning of the period. We offset these adjustments by reductions in the net income allocable to convertible redeemable preferred stockholders for those securities that were assumed to convert prior to the conversion in connection with our IPO. Those securities determined to be anti-dilutive as common stock equivalents are excluded from the calculation of diluted earnings per share; however, such securities continue to be included in the application of the two-class method to the extent applicable.
Concentrations of Credit Risk	'
	Concentrations of Credit Risk
	In the normal course of business, we are exposed to credit risk. We believe our concentration of credit risk with respect to trade receivables is limited because of the large number of customers and customer dispersion across many different geographic and economic environments. We maintain an allowance for doubtful trade accounts receivable based upon factors surrounding the credit risk of specific clients, historical trends, and other information.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	Cash includes cash on hand and cash held with banks. Cash equivalents are short-term, highly liquid investments with original maturities of three months or less when acquired. Cash and cash equivalents are deposited in or managed by major financial institutions and at times exceed Federal Deposit Insurance Corporation insurance limits.
	Cash and cash equivalents also include credit card and debit card receivables. The majority of payments due from financial intermediaries for credit card and debit card transactions process within 72 hours, except for transactions occurring on a Friday, which are generally processed the following Monday. Amounts due from financial intermediaries for these transactions classified as cash and cash equivalents totaled $1,623 and $2,356 as of December 31, 2013 and 2012, respectively.
Marketable Securities	'
	Marketable Securities
	We hold investments in marketable securities consisting of corporate debt securities, municipal debt securities, and certificates of deposit. We determine the appropriate classification of marketable securities at the time of purchase and reevaluate such determination at each balance sheet date. As of December 31, 2013, we classified all marketable securities as current as such investments are available to fund current operations.  Based on our intentions regarding our marketable securities, all marketable securities are classified as available-for-sale and are carried at fair value with unrealized gains and losses recorded as a separate component of other comprehensive income, net of income taxes on the consolidated statements of comprehensive income (loss). Realized gains and losses and declines in fair value determined to be other-than-temporary are determined using the specific-identification method and are reflected as a component of other income (expense) in the consolidated statements of operations. We periodically review our marketable securities for other-than temporary declines in fair value and write down such marketable securities when an other-than-temporary decline has occurred. No such impairments of marketable securities have been recorded to date.
Allowance for Doubtful Accounts	'
	Allowance for Doubtful Accounts
	We maintain an allowance for doubtful accounts to provide for uncollectible trade receivables. We base the allowance on historical collections, write-off experience, current economic trends, and changes in customer payment terms and other factors that may affect our ability to collect payments. As of December 31, 2013 and 2012, our allowance for doubtful accounts was $104 and $134, respectively.
Property and Equipment	'
	Property and Equipment
	We state property and equipment at cost, less accumulated depreciation, amortization, and any impairment in value. We assess long-lived assets, including our property and equipment, for impairment whenever events or changes in business circumstances arise that may indicate that the carrying amount of the long-lived assets may not be recoverable.
	We compute depreciation and amortization using the straight-line method over the following estimated useful lives of the assets:
	Leasehold improvements	3 years or the remaining term of the lease, whichever is shorter
	Telecommunications, network and computing equipment	3–5 years
	Computer software	3 years
	Furniture, fixtures and office equipment	3–5 years
Debt Issuance Costs	'
	Debt Issuance Costs
	We defer and amortize issuance costs, underwriting fees, and related expenses incurred in connection with the issuance of debt instruments using the effective interest rate method over the terms of the instruments. We charge unamortized debt issuance costs to interest expense when the related debt is extinguished.
Cost of Services	'
	Cost of Services
	Cost of services consists primarily of the direct and contract labor costs, fulfillment costs, printing and postage fees, and remediation costs to fulfill our service agreements. Cost of services also includes rent expense, facilities support, quality assurance expenses, and depreciation and amortization of long-lived assets related to the operations of our service fulfillment centers. We also include sales incentives provided to our members in cost of services.
Technology and Development	'
	Technology and Development
	Technology and development expenses consist primarily of personnel costs incurred in product development, maintenance and testing of our websites, developing solutions for new services, internal information systems and infrastructure, third-party development, and other internal-use software systems. Our development costs are primarily incurred in the United States and primarily devoted to enhancing our consumer and enterprise service offerings.
Share-Based Compensation	'
	Share-Based Compensation
	We measure share-based compensation cost at fair value, net of estimated forfeitures. We determine fair value at the grant date using the Black-Scholes option pricing model with compensation cost amortized on a straight-line basis over each award’s full vesting period, except for awards with performance conditions, which we recognize using the accelerated method. Because of the lack of sufficient historical data to calculate expected term of equity awards, we use the average of the vesting term and the contractual term to estimate the expected term for service-based options granted to employees. We estimate volatility by utilizing our historical share price and the historical volatility of comparable companies with publicly available share prices. We include share-based compensation expense in cost of services, sales and marketing, technology and development, and general and administrative expenses consistent with the respective employees’ department in the consolidated statement of operations. The fair value of restricted stock units and restricted stock is based on the value of our stock on the grant date. Compensation cost for restricted stock units is amortized on a straight-line basis over each award’s full vesting period.
Advertising Costs	'
	Advertising Costs
	We expense advertising costs as incurred, except for direct-response advertising costs. Direct-response advertising costs include telemarketing, web-based marketing, and direct mail costs related directly to membership solicitation. Advertising expense totaled approximately $86,165, $66,049, and $54,567 for the years ended December 31, 2013, 2012, and 2011, respectively.
Warrants for Shares of Preferred Stock	'
	Warrants for Shares of Convertible Redeemable Preferred Stock
	Prior to our IPO, certain warrants could be exercised to purchase shares of our convertible redeemable preferred stock. We accounted for these warrants as liabilities and recognized them at their fair value. We adjusted the carrying value of such warrants to fair value at each balance sheet date, with the change in the fair value being recorded as a component of other income (expense). In connection with our IPO, such warrants were converted into warrants to purchase shares of common stock.
Income Taxes	'
	Income Taxes
	We account for income taxes using the asset and liability method. We recognize deferred tax assets and liabilities for the future tax benefits and consequences attributable to temporary differences between the financial reporting basis of assets and liabilities and their related tax basis. We measure deferred tax assets and liabilities using the enacted tax rates expected to be in effect in the years in which those temporary differences are expected to be recovered or settled. We report any penalties and interest related to income taxes in income tax expense. We provide a valuation allowance for deferred tax assets when it is more likely than not that the related benefits will not be realized. The determination of recording or releasing tax valuation allowances is made pursuant to an assessment performed by management regarding the likelihood that we will generate future taxable income against which benefits of our deferred tax assets may or may not be realized.  This assessment requires management to exercise significant judgment and make estimates with respect to our ability to generate revenues, gross profits, operating income, and taxable income in future periods.
	We utilize a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon ultimate settlement. We consider many factors when evaluating and estimating our tax positions and tax benefits, which may require periodic adjustments and which may not accurately forecast actual outcomes.
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The carrying values of cash and cash equivalents, restricted cash, trade and other receivables, and current liabilities approximate fair values, because of the short-term nature of these items. Prior to the conversion in connection with our IPO, we carried our convertible redeemable preferred stock warrant liability at fair value.
	We determine the fair value of financial instruments using an exit price: the amount that would be received from the sale of an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. We use a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1 – observable inputs such as quoted prices in active markets; Level 2 – inputs other than the quoted prices in active markets that are observable, either directly or indirectly; and Level 3 – unobservable inputs for which there is little or no market data, which requires us to develop our own assumptions. On a recurring basis, we measure certain financial assets and liabilities at fair value, including our cash equivalents.
Recently Issued Accounting Standards	'
	Recently Issued Accounting Standards
	In February 2013, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2013-02, which supersedes and replaces the presentation requirements for reclassifications out of accumulated other comprehensive income in ASUs 2011-05 and 2011-12. The amendment requires that an entity must report the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income if the amount being reclassified is required under U.S. GAAP. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income in the same reporting period, an entity is required to cross-reference other disclosures required under U.S. GAAP that provide additional detail about those amounts. ASU 2013-02 was effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2012. We adopted the amended standards beginning January 1, 2013. As there were no amounts reclassified out of other comprehensive income during the years ended December 31, 2013 or 2012, there was no impact on our financial position, results of operations, or cash flows.
	In March 2013, the FASB issued ASU 2013-04, which provides guidance on the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date. The update requires an entity to measure obligations resulting from joint and several liability obligations for which the total amount of the obligation within the scope of the update is fixed at the reporting date, as the sum of the amount the reporting entity agreed to pay on the basis of its arrangements among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. The update also requires an entity to disclose the nature and amount of the obligation as well as other information about those obligations. The amendments in ASU 2013-04 are effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2013 and must be applied retrospectively. We do not expect the adoption of ASU 2013-04 in the first quarter of 2014 to have a material impact on our financial position, results of operations, or cash flows.
	In July 2013, the FASB issued ASU 2013-11, which requires a reporting entity to present an unrecognized tax benefit as a liability in the financial statements separate from deferred tax assets if a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available as of the reporting date to settle taxes that would result from the disallowance of the tax position or if a reporting entity does not intend to use the deferred tax asset for such purpose. The amendments in ASU 2013-11 are effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2013.  We do not expect the adoption of ASU 2013-11 to have a material impact on our consolidated financial statements.
Consumer Segment	'
Revenue Recognition	'
	Revenue Recognition—Consumer Segment
	We recognize revenue from our services provided in our consumer segment when it is probable that the economic benefits associated with the transactions will flow to us and the amount of revenue can be measured reliably. This is normally demonstrated when persuasive evidence of an arrangement exists, the fee is fixed or determinable, performance of service has been delivered, and collection is reasonably assured.
	We offer services to consumers primarily on an annual or monthly subscription basis that may include free trial periods. We typically bill subscription fees to our members’ credit card. We recognize revenue for subscriptions ratably from the last of cash receipt, activation of a member’s account, or expiration of free trial periods through the termination of the subscription period.
	We also provide consumer services for which the primary customer is a corporation or other entity that purchases identity theft protection services on behalf of its employees or customers. In such cases, we defer revenue for each member (employees or customers) until the member’s account has been activated. We then recognize revenue ratably over the remaining term of the individual subscription periods.
	We use an external sales force, referred to as Certified Referring Partners (“CRP”), that earn commissions for sales to individual members and corporations. Because we are primarily responsible for fulfillment of the service obligation, determine service specifications, and have latitude in establishing prices for our service agreements, we record all sales made by our CRPs as revenue and the related commissions as a sales and marketing expense.
Enterprise Segment	'
Revenue Recognition	'
	Revenue Recognition—Enterprise Segment
	Customer contract terms within our enterprise segment are generally monthly, and revenue is recognized when all of the following criteria are met: persuasive evidence of an arrangement exists, delivery has occurred or services have been rendered, the price is fixed or determined, and collection is reasonably assured.
	We recognize revenue from transaction-based services provided under hosted arrangements based on a negotiated fee per transaction. In some cases, we also negotiate a monthly minimum transaction fee, which may increase over the life of the contract. We bill and record transaction fees in excess of any of the monthly minimum fees as revenue in addition to the monthly minimum fees. In some instances, we receive an up-front, nonrefundable payment against which we apply the monthly minimum transaction fees. The up-front, nonrefundable payment is recorded as deferred revenue and recognized as revenue ratably over the usage period as we do not have sufficient evidence to accurately estimate a different pattern of usage. In other instances, the monthly minimum transaction fees are collected monthly, and we recognize revenue based on the negotiated monthly minimum transaction fees billed.
	We record revenue from projects where we are engaged to deliver a report at the end of the analysis upon delivery and acceptance of the report.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Estimated Useful Lives of Assets	'
	We compute depreciation and amortization using the straight-line method over the following estimated useful lives of the assets:
	Leasehold improvements	3 years or the remaining term of the lease, whichever is shorter
	Telecommunications, network and computing equipment	3–5 years
	Computer software	3 years
	Furniture, fixtures and office equipment	3–5 years

Business_CombinationsTables

Business Combinations(Tables)	12 Months Ended
	Dec. 31, 2013
Schedule of Purchase Price of Acquired Assets and Liabilities Based on Estimated Fair Values	'
	We accounted for this acquisition using the acquisition method in accordance with Accounting Standards Codification (“ASC”) 805, Business Combinations. Accordingly, we have preliminarily allocated the purchase price of the acquired assets and liabilities based on their estimated fair values as of the acquisition date as summarized in the following table:
	Net assets assumed	$	3,184
	Deferred tax assets, net – noncurrent		11,929
	Intangible assets acquired		3,880
	Goodwill		26,691
	Total purchase price consideration	$	45,684
Preliminary Allocation of Purchase Price to Net Liabilities Assumed	'
	The following is a description of the allocation of the purchase price to the net assets acquired:
	Cash	$	3,315
	Prepaid expenses and other current assets		128
	Total tangible assets acquired		3,443
	Accrued expenses		(145	)
	Deferred revenue		(114	)
	Total liabilities assumed		(259	)
	Net assets assumed	$	3,184
Acquired Finite Lived Intangible Assets and Weighted Average Useful Life	'
	The following were the identified intangible assets acquired at their preliminary fair value and the respective preliminary estimated periods over which such assets will be amortized:
					Weighted-
					Average
					Useful Life
		Amount			(in years)
	Trade name and trademarks	$	60			1
	Customer relationships		530			1
	Technology		3,290			7
		$	3,880

Marketable_Securities_Tables

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2013
Summary of Marketable Securities Designated as Available-for-Sale	'
	The following is a summary of marketable securities designated as available-for-sale as of December 31, 2013:
				Gross		Gross
		Amortized		Unrealized		Unrealized			Estimated
		Cost		Gains		Losses			Fair Value
	Corporate bonds	$	37,399	$	1	$	(29	)	$	37,371
	Municipal bonds		10,820		2		(3	)		10,819
	Certificates of deposit		498		-		-			498
	Total marketable securities	$	48,717	$	3	$	(32	)	$	48,688
Summary of Amortized Cost and Estimated Fair Value of Marketable Securities by Maturity	'
	The following is a summary of amortized cost and estimated fair value of marketable securities as of December 31, 2013, by maturity:
				Gross		Gross
		Amortized		Unrealized		Unrealized			Estimated
		Cost		Gains		Losses			Fair Value
	Due in one year or less	$	47,398	$	3	$	(32	)	$	47,369
	Due after one year		1,319		-		-			1,319
	Total marketable securities	$	48,717	$	3	$	(32	)	$	48,688

Trade_and_Other_Receivables_Ta

Trade and Other Receivables (Tables)	12 Months Ended
	Dec. 31, 2013
Trade and Other Receivables	'
	Trade and other receivables consisted of the following as of December 31:
		2013			2012
	Trade receivables	$	5,796		$	6,125
	Other receivables		5,214			1,569
	Less allowance for doubtful accounts		(104	)		(134	)
		$	10,906		$	7,560

Property_and_Equipment_Net_Tab

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2013
Property and Equipment	'
	Property and equipment consisted of the following as of December 31:
		2013			2012
	Computer software	$	12,318		$	9,003
	Telecommunications, network and computing equipment		12,923			8,039
	Leasehold improvements		4,223			4,140
	Furniture, fixtures and office equipment		2,980			2,859
			32,444			24,041
	Less accumulated depreciation and amortization		(21,081	)		(17,514	)
			11,363			6,527
	Assets not yet placed in service		5,141			3,174
		$	16,504		$	9,701

Other_Intangible_Assets_Tables

Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2013
Acquisition Related Intangible Assets	'
	Our acquisition-related intangible assets are as follows:
		Gross					Net
		Carrying		Accumulated			Carrying
		Value		Amortization			Amount
	Trade name and trademarks	$	4,060	$	(1,439	)	$	2,621
	Technology		36,290		(8,485	)		27,805
	Customer relationships		21,030		(4,243	)		16,787
		$	61,380	$	(14,167	)	$	47,213
Estimated Future Amortization of Acquisition-related Intangible Asset	'
	Amortization expense for the years ended December 31, 2013, 2012, and 2011 was $7,909 and $6,258, and zero, respectively. Estimated future amortization of acquisition-related intangible asset for future periods is as follows:
	Years Ending December 31,
	2014	$	8,899
	2015		8,334
	2016		8,334
	2017		7,698
	2018		7,534
	Thereafter		6,414
		$	47,213

Recovered_Sheet1

Accrued Expenses and Other Liabilities (Tables)	12 Months Ended
	Dec. 31, 2013
Accrued Expenses and Other Liabilities	'
	Accrued expenses and other liabilities consisted of the following as of December 31:
		2013		2012
	Marketing, commissions and other services	$	9,678	$	11,814
	Employee salaries, wages, and benefits		15,619		10,643
	Sales, property and income taxes		928		1,536
	Consulting, contract labor and professional fees		7,496		2,176
	Other		1,205		1,160
		$	34,926	$	27,329

Operating_Leases_Tables

Operating Leases (Tables)	12 Months Ended
	Dec. 31, 2013
Summary of Future Minimum Lease Payments for All Outstanding Lease Agreements	'
	The following summarizes the future minimum lease payments for outstanding operating lease agreements as of December 31, 2013:
	2014	$	3,276
	2015		4,922
	2016		5,112
	2017		4,919
	2018		3,591
	Thereafter		18,743
		$	40,563

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2013
Summary of Preferred Stock Issued	'
	On March 14, 2012, we issued the following convertible redeemable preferred stock:
			Issue Date		Gross		Shares
					Amount
	Series E Convertible Redeemable Preferred Stock		March 14, 2012		$	86,843		11,486,999
	Series E-1 Convertible Redeemable Preferred Stock		14-Mar-12			11,542		1,586,778	(1)
	Series E-2 Convertible Redeemable Preferred Stock		14-Mar-12			17,275		2,284,960
	-1	All shares were issued as purchase consideration for ID Analytics.
Warrant Purchase	'
	As of December 31, 2013, we had the following warrants to purchase common stock outstanding:
	Expiration Date		Shares				Exercise
							Price
	October 3, 2014			2,334,044					0.7
	December 19, 2014			166,666					4.5

ShareBased_Compensation_Tables

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2013
Activity of Stock Options, Including Performance-Based Options	'
	The following table summarizes information on the activity of stock options, including performance-based options, under the 2006 and 2012 Plans for the years ended December 31:
		2013							2012						2011
		Shares			Weighted				Shares			Weighted			Shares			Weighted
					Average							Average						Average
					Exercise							Exercise						Exercise
					Price Per							Price Per						Price Per
					Share							Share						Share
	Outstanding at beginning of year		12,273,815		$	4.24				8,660,771		$	3.07			9,053,803		$	2.88
	Granted		5,494,969			11.57				5,127,486			6.19			1,477,013			4.26
	Exercised		(4,489,459	)		3.27				(306,819	)		2.39			(856,207	)		2.05
	Expired		(33,951	)		3.22				(357,482	)		3.7			(466,852	)		4.41
	Forfeited		(1,861,123	)		7.4				(850,141	)		4.91			(546,986	)		3.61
	Outstanding at end of year		11,384,251		$	7.62				12,273,815		$	4.22			8,660,771		$	3.07
	Exercisable at end of year		4,235,609		$	4.39				6,379,166		$	2.98			5,113,662		$	2.78
Additional Information on Stock Options, Including Performance-Based Options, Outstanding and Exercisable	'
	The following table summarizes additional information about stock options, including performance-based options, outstanding and exercisable as of December 31, 2013:
		Options Outstanding										Options Exercisable
	Range of	Shares Under			Weighted-			Weighted-				Shares Under		Weighted-
	Exercise Prices	Option			Average			Average				Option		Average
					Remaining			Exercise Price						Exercise Price
					Contractual			Per Share						Per Share
					Life
	$0.01 - $3.50		2,243,070			4.96		$	2.43				2,137,953	$	2.43
	$3.51 - $7.00		3,250,734			7.54			4.85				1,401,826		4.62
	$7.01 - $10.50		2,055,167			8.83			9.21				344,271		8.78
	$10.51 - $14.00		3,264,580			9.34			11.38				351,559		11.08
	$14.01 - $17.50		570,700			9.84			15.55				-		-
			11,384,251										4,235,609
Weighted-Average Assumptions of Stock Options using Black-Scholes Option Pricing Model	'
	The weighted-average fair value of our outstanding stock options was $5.88, $2.57, and $1.29, for the years ended December 31, 2013, 2012, and 2011, respectively. Such amounts were estimated using the Black-Scholes option pricing model with the following weighted-average assumptions at December 31:
		2013				2012				2011
	Expected volatility		106.1	%			94.6	%			60	%
	Expected dividend yield		0	%			0	%			0	%
	Risk-free interest rate		1.3	%			1.2	%			2	%
	Expected term (years)	6.05				6.15				6.11
Unvested Restricted Stock Units Activity	'
	The following table summarizes unvested restricted stock units activity under the 2012 Plan for the years ended December 31, 2012, and 2013:
		Restricted			Weighted -
		Stock Units			Average Grant
					Date Fair
					Value (per
					share)
	Unvested at December 31, 2011		-		$	-
	Granted		276,250			9
	Vested		(8,750	)		9
	Forfeited		-			-
	Unvested at December 31, 2012		267,500		$	9
	Granted		438,879			13.9
	Vested		(128,136	)		9.34
	Forfeited		-			-
	Unvested at December 31, 2013		578,243		$	12.65

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value of Financial Assets and Liabilities	'
	As of December 31, 2013 and December 31, 2012, the fair value of our financial assets was as follows:
			Level 1		Level 2		Level 3		Total
	31-Dec-13
	Assets:
	Commercial paper (1)		$	-	$	45,110	$	-	$	45,110
	Money market funds (1)			911		-		-		911
	Corporate bonds (2)			-		37,371		-		37,371
	Municipal bonds (2)			-		10,819		-		10,819
	Certificates of deposit (2)			-		498		-		498
	Total assets measured at fair value		$	911	$	93,798	$	-	$	94,709
	31-Dec-12
	Assets:
	Commercial paper (1)		$	-	$	35,023	$	-	$	35,023
	Total assets measured at fair value		$	-	$	35,023	$	-	$	35,023
	-1	Classified in cash and cash equivalents
	-2	Classified in marketable securities

Net_Income_Loss_Per_Share_Tabl

Net Income (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Basic and Diluted Net Income (Loss) per Share Attributable to Common Stockholders	'
	The following table sets forth the computation of basic and diluted net income available (loss attributable) per share attributable to common stockholders for the years ended December 31:
		2013		2012			2011
	Net income (loss)	$	52,451	$	23,503		$	(4,257	)
	Less:
	Accretion of convertible redeemable preferred
	stock redemption premium		-		(9,378	)		(18,926	)
	Beneficial conversion feature on convertible
	redeemable preferred stock		-		(2,452	)		-
	Net income allocable to convertible redeemable
	preferred stockholders		-		(5,504	)		-
	Net income available (loss attributable) to common
	stockholders		52,451		6,169			(23,183	)
	Less:
	Change in fair value of warrant liabilities		-		(4,382	)		-
	Accretion of convertible redeemable preferred
	stock redemption premium for shares assumed
	issued in exercise of warrants		-		(898	)		-
	Plus:
	Net income allocable to convertible redeemable
	preferred stockholders		-		4,444			-
	Diluted net income available (loss attributable)
	to common stockholders	$	52,451	$	5,333		$	(23,183	)
	Denominator (basic):
	Weighted average common shares outstanding		88,635,832		35,081,863			18,725,305
	Denominator (diluted):
	Weighted average common shares outstanding		88,635,832		35,081,863			18,725,305
	Dilutive stock options and awards outstanding		4,991,320		4,088,101			-
	Weighted average common shares from
	preferred stock		-		22,528,878			-
	Weighted average common shares from warrants		2,318,422		491,860			-
	Net weighted average common shares outstanding		95,945,574		62,190,702			18,725,305
	Net income available (loss attributable) per share to
	common stockholders:
	Basic	$	0.59	$	0.18		$	(1.24	)
	Diluted	$	0.55	$	0.09		$	(1.24	)
Stock Options, Warrants to Purchase Common and Preferred Stock and Convertible Redeemable Preferred Stock Excluded from Computation of Diluted Net Income (Loss) Per Share	'
	The following weighted-average number of outstanding employee stock options, restricted stock units, warrants to purchase common and convertible redeemable preferred stock, and convertible redeemable preferred stock were excluded from the computation of diluted net loss per share for the years ended December 31:
		2013		2012			2011
	Stock options outstanding		4,315,153		-			2,551,074
	Restricted stock units		45,673		-			-
	Common equivalent shares from stock warrants		-		3,585,996			2,727,702
	Common shares from convertible redeemable
	preferred stock		-		8,770,427			29,239,607
			4,360,826		12,356,423			34,518,383

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Components of Income Tax Provision	'
	The components of income tax provision were as follows at December 31:
		2013			2012			2011
	Current:
	U.S. federal	$	30		$	388		$	36
	U.S. state and local taxes		58			67			178
	Total current		88			455			214
	Deferred:
	U.S. federal		(36,631	)		(11,877	)		-
	U.S. state and local taxes		(2,503	)		(2,308	)		-
	Foreign		(63	)
	Total deferred		(39,197	)		(14,185	)		-
	Total income tax (benefit) expense	$	(39,109	)	$	(13,730	)	$	214
Reconciliation of Income Tax at U.S. Statutory Rate to Effective Income Tax Rate	'
	A reconciliation of income tax computed at the U.S. statutory rate to the effective income tax rate is as follows at December 31:
			2013			2012			2011
	Statutory federal income tax rate		35	%		35	%		34	%
	State tax expense, net of federal benefit		3.8	%		6.1	%		-4.5	%
	Nondeductible expense related to stock warrants		0	%		-11.2	%		-72.8	%
	Nondeductible expense related to embedded derivative		0	%		10	%		0	%
	Other nondeductible expenses		6.2	%		2.7	%		-2.5	%
	Effect of change in income tax rates		-2.4	%		14.4	%		5.1	%
	Impact of state net operating losses		7	%		-11.4	%		15.5	%
	Stock options		0.1	%		0.7	%		-4.8	%
	Other		0	%		1	%		0.6	%
	Expired net operating losses		16.3	%		0	%		0	%
	Reduction in valuation allowance due to business
	combination		0	%		-145.1	%		0	%
	Change in valuation allowance		-359.1	%		-42.7	%		24.1	%
	Total expense		-293.1	%		-140.5	%		-5.3	%
Summary of Components of Deferred Tax Assets and Liabilities	'
	The following is a summary of the components of our deferred tax assets and liabilities at December 31:
			2013			2012
	Deferred tax assets:
	Net operating losses and credit carryforwards	$	62,570		$	62,307
	Stock options		6,580			5,513
	Deferred rent		1,692			196
	Deferred revenue		13			44
	Accrued expenses		795			1,310
	Other		118			-
	Total deferred tax assets		71,768			69,370
	Valuation allowance		(1,229	)		(49,146	)
	Net deferred tax assets	$	70,539		$	20,224
	Deferred tax liabilities:
	Property and equipment	$	(18,777	)	$	(20,012	)
	Other		(627	)		(212	)
	Total deferred tax liabilities		(19,404	)		(20,224	)
	Net deferred tax assets	$	51,135		$	-

Segment_Reporting_Tables

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2013
Financial Information of Segments	'
	Financial information about our segments for the year ended December 31, 2013 and as of December 31, 2013 was as follows:
		Consumer		Enterprise			Eliminations			Total
	Revenue
	External customers	$	340,121	$	29,537		$	-		$	369,658
	Intersegment revenue		-		5,316			(5,316	)		-
	Income (loss) from operations		23,997		(10,405	)		-			13,592
	Goodwill		96,583		59,537			-			156,120
	Total assets		349,394		114,337			(481	)		463,250
	Financial information about our segments for the year ended December 31, 2012 and as of December 31, 2012 was as follows:
		Consumer		Enterprise			Eliminations			Total
	Revenue
	External customers	$	254,678	$	21,750		$	-		$	276,428
	Intersegment revenue		-		3,506			(3,506	)		-
	Income (loss) from operations		18,840		(5,747	)		-			13,093
	Goodwill		69,891		59,537			-			129,428
	Total assets		213,564		129,245			(3,221	)		339,588

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2013
Schedule of Selected Quarterly Financial Data (unaudited)	'
	The following table sets forth certain unaudited quarterly results of operations of the Company for the years ended December 31, 2013 and 2012.  In the opinion of management, this information has been prepared on the same basis as the audited consolidated financial statements and all necessary adjustments, consisting only of normal recurring adjustments, have been included in the amounts below for a fair statement of the quarterly information when read in conjunction with the audited consolidated financial statements and related notes included elsewhere in this Annual Report on Form 10-K:
		Three Months Ended
		Dec 31,		Sep 30,		Jun 30,			Mar 31,			Dec 31,		Sep 30,			Jun 30,			Mar 31,
		2013		2013		2013			2013			2012		2012			2012			2012
		(in thousands, except per share data)
	Revenue:
	Consumer revenue	$	94,068	$	88,386	$	82,574		$	75,094		$	70,775	$	65,579		$	61,616		$	56,708
	Enterprise revenue		8,237		7,353		6,946			7,001			8,041		6,538			6,267			904
	Total revenue		102,305		95,739		89,520			82,095			78,816		72,117			67,883			57,612
	Gross profit	$	76,021		70,804		64,293			58,291			56,627		52,355			48,758			38,772
	Income (loss) from operations	$	14,041		5,658		(2,191	)		(3,916	)		5,700		6,223			1,379			(209	)
	Net income (loss)	$	53,206	$	5,427	$	(2,065	)	$	(4,117	)	$	4,080	$	7,868		$	(6,898	)	$	18,453
	Basic net income (loss) per share	$	0.58	$	0.06	$	(0.02	)	$	(0.05	)	$	0.01	$	0.06		$	(0.56	)	$	0.34
	Diluted net income (loss) per share	$	0.54	$	0.06	$	(0.02	)	$	(0.05	)	$	0.01	$	(0.16	)	$	(0.59	)	$	0.22

Corporation_Information_Additi

Corporation Information - Additional Information (Detail) (USD $)	12 Months Ended		1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Oct. 31, 2012
			IPO
Basis Of Presentation And Organization [Line Items]	'	'	'
Acquisition date of ID Analytics Inc.	14-Mar-12	'	'
Common stock shares issued and sold	91,441,771	86,561,320	15,500,000
Common stock public offering price per share	'	'	$9
Net proceeds received from IPO	'	'	$125,663,000
Underwriting discount	'	'	9,765,000
Other offering expenses	'	'	4,072,000
Convertible redeemable preferred stock converted into common stock	'	'	51,320,437
Payments to Acquire Businesses, Net of Cash Acquired	$42,369	'	'

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Segment
Summary Of Significant Accounting Policies [Line Items]	'	'	'
Number of operating segments	2	'	'
Impairment of goodwill	$0	'	'
Amounts due from financial intermediaries classified as cash and cash equivalents	1,623	2,356	'
Restricted cash	0	0	'
Allowance for doubtful accounts	104	134	'
Advertising expense	$86,165	$66,049	$54,567
Minimum	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'
Percentage of tax benefit likely to be realized upon settlement	50.00%	'	'

Estimated_Useful_Lives_of_Prop

Estimated Useful Lives of Property and Equipment (Detail)	12 Months Ended
	Dec. 31, 2013
Leasehold Improvements	'
Property Plant And Equipment [Line Items]	'
Property and equipment, useful life description	'3 years or the remaining term of the lease, whichever is shorter
Leasehold Improvements | Maximum	'
Property Plant And Equipment [Line Items]	'
Property and equipment, useful life	'3 years
Telecommunications, Network and Computing Equipment | Maximum	'
Property Plant And Equipment [Line Items]	'
Property and equipment, useful life	'5 years
Telecommunications, Network and Computing Equipment | Minimum	'
Property Plant And Equipment [Line Items]	'
Property and equipment, useful life	'3 years
Computer Software	'
Property Plant And Equipment [Line Items]	'
Property and equipment, useful life	'3 years
Furniture, Fixtures and Office Equipment | Maximum	'
Property Plant And Equipment [Line Items]	'
Property and equipment, useful life	'5 years
Furniture, Fixtures and Office Equipment | Minimum	'
Property Plant And Equipment [Line Items]	'
Property and equipment, useful life	'3 years

Schedule_of_Purchase_Price_of_

Schedule of Purchase Price of Acquired Assets and Liabilities Based on Estimated Fair Values (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]	'	'
Intangible assets acquired	$3,880	'
Goodwill	156,120	129,428
Lemon Inc	'	'
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]	'	'
Net assets assumed	3,184	'
Deferred tax assets, net – noncurrent	11,929	'
Intangible assets acquired	3,880	'
Goodwill	26,691	'
Total purchase price consideration	$45,684	'

Business_Combinations_Addition

Business Combinations - Additional Information (Detail) (USD $)

12 Months Ended

3 Months Ended

3 Months Ended

1 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2012

Dec. 11, 2013

Dec. 31, 2013

Technology

Customer relationships

Tradename And Trademarks

ID Analytics

ID Analytics

ID Analytics

ID Analytics

ID Analytics

ID Analytics

ID Analytics

Lemon Inc

Lemon Inc

Consumer Segment

Enterprise Segment

Trade name and trademarks

Technology

Customer relationships

Series E One Preferred Stock

Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash paid for acquisition

$42,369

'

'

'

'

$166,474,000

'

'

'

'

'

'

$42,369,000

'

Purchase price net of cash acquired

42,369,000

157,430,000

'

'

'

157,430,000

'

'

'

'

'

'

3,315,000

'

Number of shares issued at the acquisition

'

'

'

'

'

'

'

'

'

'

'

1,586,778

'

'

Fair value of the shares issued at the acquisition

'

'

'

'

'

'

'

'

'

'

'

19,476,000

'

'

Goodwill

156,120,000

129,428,000

'

'

'

129,428,000

69,891,000

59,537,000

'

'

'

'

'

26,691,000

Intangible assets acquired

3,880,000

'

3,290,000

530,000

60,000

57,500,000

'

'

4,000,000

33,000,000

20,500,000

'

'

3,880,000

Net liabilities assumed

'

'

'

'

'

978,000

'

'

'

'

'

'

'

'

Weighted average useful life (in years)

'

'

'7 years

'1 year

'1 year

'7 years 7 months 6 days

'

'

'

'

'

'

'

'

Acquisition date of ID Analytics Inc.

14-Mar-12

'

'

'

'

'

'

'

'

'

'

'

'

11-Dec-13

Payments to Acquire Businesses, Net of Cash Acquired

42,369

'

'

'

'

166,474,000

'

'

'

'

'

'

42,369,000

'

Royalty rate

'

'

12.75%

'

1.50%

'

'

'

'

'

'

'

'

'

Discount rate

'

'

18.50%

18.50%

18.50%

'

'

'

'

'

'

'

'

'

Tax rate

'

'

39.30%

39.30%

39.30%

'

'

'

'

'

'

'

'

'

Economic life

'

'

'7 years

'1 year

'1 year

'

'

'

'

'

'

'

'

'

Transaction cost

1,068,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Pro forma consolidated revenue

370,409,000

276,623,000

'

'

'

'

'

'

'

'

'

'

'

'

Pro forma consolidated net income (loss)

$48,966,000

$17,567,000

'

'

'

'

'

'

'

'

'

'

'

'

Preliminary_Allocation_of_Purc

Preliminary Allocation of Purchase Price to Net Liabilities Assumed (Detail) (Lemon Inc, USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Lemon Inc	'
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]	'
Cash	$3,315
Prepaid expenses and other current assets	128
Total tangible assets acquired	3,443
Accrued expenses	-145
Deferred revenue	-114
Total liabilities assumed	-259
Net assets assumed	$3,184

Acquired_Finite_Lived_Intangib

Acquired Finite Lived Intangible Assets and Weighted Average Useful Life (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]	'
Intangible assets acquired	$3,880
Tradename And Trademarks	'
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]	'
Intangible assets acquired	60
Weighted average useful life (in years)	'1 year
Customer relationships	'
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]	'
Intangible assets acquired	530
Weighted average useful life (in years)	'1 year
Technology	'
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items]	'
Intangible assets acquired	$3,290
Weighted average useful life (in years)	'7 years

Summary_of_Marketable_Securiti

Summary of Marketable Securities Designated as Available-for-Sale (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule Of Marketable Securities [Line Items]	'
Amortized Cost	$48,717
Gross Unrealized Gains	3
Gross Unrealized Losses	-32
Estimated Fair Value	48,688
Corporate bonds	'
Schedule Of Marketable Securities [Line Items]	'
Amortized Cost	37,399
Gross Unrealized Gains	1
Gross Unrealized Losses	-29
Estimated Fair Value	37,371
Municipal bonds	'
Schedule Of Marketable Securities [Line Items]	'
Amortized Cost	10,820
Gross Unrealized Gains	2
Gross Unrealized Losses	-3
Estimated Fair Value	10,819
Certificates of deposit	'
Schedule Of Marketable Securities [Line Items]	'
Amortized Cost	498
Gross Unrealized Gains	'
Gross Unrealized Losses	'
Estimated Fair Value	$498

Summary_of_Amortized_Cost_and_

Summary of Amortized Cost and Estimated Fair Value of Marketable Securities by Maturity (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule Of Marketable Securities [Line Items]	'
Amortized Cost	$48,717
Gross Unrealized Gains	3
Gross Unrealized Losses	-32
Estimated Fair Value	48,688
Due in one year or less	'
Schedule Of Marketable Securities [Line Items]	'
Amortized Cost	47,398
Gross Unrealized Gains	3
Gross Unrealized Losses	-32
Estimated Fair Value	47,369
Due after one year	'
Schedule Of Marketable Securities [Line Items]	'
Amortized Cost	1,319
Gross Unrealized Gains	'
Gross Unrealized Losses	'
Estimated Fair Value	$1,319

Summary_of_Trade_and_Other_Rec

Summary of Trade and Other Receivables (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accounts Notes And Loans Receivable [Line Items]	'	'
Trade receivables	$5,796	$6,125
Other receivables	5,214	1,569
Less allowance for doubtful accounts	-104	-134
Trade and other receivables, net	$10,906	$7,560

Summary_of_Property_and_Equipm

Summary of Property and Equipment (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Property Plant And Equipment [Line Items]	'	'
Computer software	$12,318	$9,003
Telecommunications, network and computing equipment	12,923	8,039
Leasehold improvements	4,223	4,140
Furniture, fixtures and office equipment	2,980	2,859
Property, Plant and Equipment, Gross, Total	32,444	24,041
Less accumulated depreciation and amortization	-21,081	-17,514
Property Plant And Equipment Gross After Accumulated Depreciation, Total	11,363	6,527
Assets not yet placed in service	5,141	3,174
Property and equipment, net	$16,504	$9,701

Property_and_Equipment_Net_Add

Property and Equipment, Net - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property Plant And Equipment [Line Items]	'	'	'
Depreciation expense	$4,887	$4,169	$3,740

Acquisitionrelated_Intangible_

Acquisition-related Intangible Assets (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Acquired Finite Lived Intangible Assets [Line Items]	'
Gross Carrying Value	$61,380
Accumulated Amortization	-14,167
Net Carrying Amount	47,213
Trade name and trademarks	'
Acquired Finite Lived Intangible Assets [Line Items]	'
Gross Carrying Value	4,060
Accumulated Amortization	-1,439
Net Carrying Amount	2,621
Technology	'
Acquired Finite Lived Intangible Assets [Line Items]	'
Gross Carrying Value	36,290
Accumulated Amortization	-8,485
Net Carrying Amount	27,805
Customer relationships	'
Acquired Finite Lived Intangible Assets [Line Items]	'
Gross Carrying Value	21,030
Accumulated Amortization	-4,243
Net Carrying Amount	$16,787

Amortization_Expense_of_Intang

Amortization Expense of Intangible Assets (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Acquired Finite Lived Intangible Assets [Line Items]	'
2014	$8,899
2015	8,334
2016	8,334
2017	7,698
2018	7,534
Thereafter	6,414
Net Carrying Amount	$47,213

Other_Intangible_Assets_Additi

Other Intangible Assets - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Acquired Finite Lived Intangible Assets [Line Items]	'	'
Amortization expense	$7,909	$6,258

Summary_of_Accrued_Expenses_an

Summary of Accrued Expenses and Other Liabilities (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accrued Expenses And Other Liabilities [Line Items]	'	'
Marketing, commissions and other services	$9,678	$11,814
Employee salaries, wages, and benefits	15,619	10,643
Sales, property and income taxes	928	1,536
Consulting, contract labor and professional fees	7,496	2,176
Other	1,205	1,160
Accrued expenses and other liabilities	$34,926	$27,329

Financing_Arrangements_Additio

Financing Arrangements - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Jan. 09, 2013	Dec. 31, 2013	Dec. 31, 2012	Aug. 31, 2013	Feb. 07, 2012
Line Of Credit Facility [Line Items]	'	'	'	'	'
Credit agreement	'	'	'	'	$70,000
Maturity date	'	7-Feb-16	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Line of credit interest rate	'	0.13%	'	'	'
Amortization of debt issuance cost	'	'	1,760	'	'
Write-off of deferred financing costs from early payoff of debt	'	'	1,443	'	'
Letter of credit	'	'	2,000	1,200	'
Letters of credit Released date	'	'	1-Jul-12	'	'
Revolving line of credit, maturity date	9-Jan-18	'	'	'	'
Unused commitment fees paid	'	267	'	'	'
Initial applicable rate	'	0.25%	'	'	'
Base Rate	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Initial applicable rate	'	0.50%	'	'	'
Eurodollar Rate Loans	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Initial applicable rate	'	1.50%	'	'	'
Letter Of Credit Sub Facility	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Revolving line of credit	10,000	'	'	'	'
Swing Line Loan Subfacility	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Revolving line of credit	5,000	'	'	'	'
Federal Funds Rate	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Interest rate above LIBOR	'	0.50%	'	'	'
Eurodollar | Base Rate	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Interest rate above LIBOR	'	1.00%	'	'	'
Letter of Credit	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Letters of credit issued	'	100	1,300	'	'
Initial applicable rate	'	1.50%	'	'	'
Minimum	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Interest rate above LIBOR	'	3.75%	'	'	'
Revolving line of credit	85,000	'	'	'	'
Commitment fee applicable rate	'	0.25%	'	'	'
Minimum | Eurodollar | Base Rate	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Applicable interest rate	'	0.50%	'	'	'
Minimum | Eurodollar | Eurodollar Rate Loans	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Applicable interest rate	'	1.50%	'	'	'
Maximum	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Interest rate above LIBOR	'	4.75%	'	'	'
Revolving line of credit	110,000	'	'	'	'
Commitment fee applicable rate	'	0.50%	'	'	'
Maximum | Eurodollar | Base Rate	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Applicable interest rate	'	1.25%	'	'	'
Maximum | Eurodollar | Eurodollar Rate Loans	'	'	'	'	'
Line Of Credit Facility Covenant Compliance [Line Items]	'	'	'	'	'
Applicable interest rate	'	2.25%	'	'	'
Term Loan	'	'	'	'	'
Line Of Credit Facility [Line Items]	'	'	'	'	'
Credit agreement	'	'	'	'	68,000
Line of Credit	'	'	'	'	'
Line Of Credit Facility [Line Items]	'	'	'	'	'
Credit agreement	'	'	'	'	$2,000

Operating_Leases_Additional_In

Operating Leases - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Leased Assets [Line Items]	'	'	'
Rent expense incurred under operating leases	$3,546	$2,758	$1,764

Summary_of_Future_Minimum_Leas

Summary of Future Minimum Lease Payments for All Outstanding Lease Agreements (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Operating Leased Assets [Line Items]	'
2014	$3,276
2015	4,922
2016	5,112
2017	4,919
2018	3,591
Thereafter	18,743
Operating Leases, Future Minimum Payments Due, Total	$40,563

Summary_of_Preferred_Stock_Iss

Summary of Preferred Stock Issued (Detail) (USD $)	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Series E Preferred Stock	'
Class Of Stock [Line Items]	'
Issue Date	14-Mar-12
Gross Amount	$86,843
Shares	11,486,999
Series E One Preferred Stock	'
Class Of Stock [Line Items]	'
Issue Date	14-Mar-12
Gross Amount	11,542
Shares	1,586,778	[1]
Series E Two Preferred Stock	'
Class Of Stock [Line Items]	'
Issue Date	14-Mar-12
Gross Amount	$17,275
Shares	2,284,960
[1]	All shares were issued as purchase consideration for ID Analytics.

Warrants_Purchase_Detail

Warrants Purchase (Detail) (Common Stock)	12 Months Ended
	Dec. 31, 2013
Expiration Date October 3, 2014	'
Class Of Warrant Or Right [Line Items]	'
Expiration Date	3-Oct-14
Number	2,334,044
Exercise Price	0.7
Expiration Date December 19, 2014	'
Class Of Warrant Or Right [Line Items]	'
Expiration Date	19-Dec-14
Number	166,666
Exercise Price	4.5

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Oct. 09, 2012	Oct. 09, 2012	Oct. 09, 2012	Dec. 31, 2012	Mar. 14, 2012
				IPO	Series B, C, D and E1 preferred shares converted on 1 for 1 basis into common stock	Series A preferred shares converted on 1 for 1.03 basis into common stock	Series E and E-2 preferred shares converted on 1 for 1.49 basis into common stock	Series E One Preferred Stock	Series E One Preferred Stock
					IPO	IPO	IPO
Class Of Stock [Line Items]	'	'	'	'	'	'	'	'	'
Number of shares issued upon preferred share conversion	'	'	'	'	24,208,738	6,617,647	20,494,052	'	'
Initial public offering price	'	$9	'	'	'	'	'	'	'
Beneficial conversion feature related to Series E and Series E-2 preferred stock	'	$2,452	'	'	'	'	'	'	'
Fair value determined	'	'	'	'	'	'	'	10,719	7,934
Change in fair value of embedded derivative	'	2,785	'	'	'	'	'	'	'
Preferred stock shares authorized	10,000,000	10,000,000	'	'	'	'	'	'	'
Preferred stock shares par value	$0.00	$0.00	'	'	'	'	'	'	'
Preferred stock shares issued	'	'	'	'	'	'	'	'	'
Preferred stock shares outstanding	'	'	'	'	'	'	'	'	'
Other income (expense)	($21)	($5)	($5)	$4,372	'	'	'	'	'
Common stock shares authorized	300,000,000	300,000,000	'	'	'	'	'	'	'
Common stock par value	$0.00	$0.00	'	'	'	'	'	'	'
Common stock shares outstanding	91,441,771	86,561,320	'	'	'	'	'	'	'

Activity_of_Stock_Options_Incl

Activity of Stock Options, Including Performance-Based Options (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Shares	'	'	'
Outstanding at beginning of year	12,273,815	8,660,771	9,053,803
Granted	5,494,969	5,127,486	1,477,013
Exercised	-4,489,459	-306,819	-856,207
Expired	-33,951	-357,482	-466,852
Forfeited	-1,861,123	-850,141	-546,986
Outstanding at end of year	11,384,251	12,273,815	8,660,771
Exercisable at end of year	4,235,609	6,379,166	5,113,662
Weighted Average Exercise Price Per Share	'	'	'
Outstanding at beginning of year	$4.22	$3.07	$2.88
Granted	$11.57	$6.19	$4.26
Exercised	$3.27	$2.39	$2.05
Expired	$3.22	$3.70	$4.41
Forfeited	$7.40	$4.91	$3.61
Outstanding at end of year	$7.62	$4.22	$3.07
Exercisable at end of year	$4.39	$2.98	$2.78

Additional_Information_on_Stoc

Additional Information on Stock Options, Including Performance-Based Options, Outstanding and Exercisable (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]	'
Range of Exercise Prices, Lower Limit	$7.51
Range of Exercise Prices, Upper Limit	$9
Options Outstanding, Shares Under Option	11,384,251
Options Exercisable, Shares Under Option	4,235,609
Range of Exercise Prices $0.01 - $3.50	'
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]	'
Range of Exercise Prices, Lower Limit	$0.01
Range of Exercise Prices, Upper Limit	$1.50
Options Outstanding, Shares Under Option	2,243,070
Options Outstanding, Weighted-Average Remaining Contractual Life	'4 years 11 months 19 days
Options Outstanding, Weighted-Average Exercise Price Per Share	$2.43
Options Exercisable, Shares Under Option	2,137,953
Options Exercisable, Weighted-Average Exercise Price per Share	$2.43
Range of Exercise Prices $3.51 - $7.00	'
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]	'
Range of Exercise Prices, Lower Limit	$1.51
Range of Exercise Prices, Upper Limit	$3
Options Outstanding, Shares Under Option	3,250,734
Options Outstanding, Weighted-Average Remaining Contractual Life	'7 years 6 months 18 days
Options Outstanding, Weighted-Average Exercise Price Per Share	$4.85
Options Exercisable, Shares Under Option	1,401,826
Options Exercisable, Weighted-Average Exercise Price per Share	$4.62
Range of Exercise Prices $7.01 - $10.50	'
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]	'
Range of Exercise Prices, Lower Limit	$3.01
Range of Exercise Prices, Upper Limit	$4.50
Options Outstanding, Shares Under Option	2,055,167
Options Outstanding, Weighted-Average Remaining Contractual Life	'8 years 10 months 6 days
Options Outstanding, Weighted-Average Exercise Price Per Share	$9.21
Options Exercisable, Shares Under Option	344,271
Options Exercisable, Weighted-Average Exercise Price per Share	$8.78
Range of Exercise Prices $10.51 - $14.00	'
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]	'
Range of Exercise Prices, Lower Limit	$4.51
Range of Exercise Prices, Upper Limit	$6
Options Outstanding, Shares Under Option	3,264,580
Options Outstanding, Weighted-Average Remaining Contractual Life	'9 years 4 months 2 days
Options Outstanding, Weighted-Average Exercise Price Per Share	$11.38
Options Exercisable, Shares Under Option	351,559
Options Exercisable, Weighted-Average Exercise Price per Share	$11.08
Range of Exercise Prices $14.01 - $17.50	'
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]	'
Range of Exercise Prices, Lower Limit	$6.01
Range of Exercise Prices, Upper Limit	$7.50
Options Outstanding, Shares Under Option	570,700
Options Outstanding, Weighted-Average Remaining Contractual Life	'9 years 6 months 29 days
Options Outstanding, Weighted-Average Exercise Price Per Share	$15.55

WeightedAverage_Assumptions_of

Weighted-Average Assumptions of Stock Options Using Black-Scholes Option Pricing Model (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'	'
Expected volatility	106.10%	94.60%	60.00%
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	1.30%	1.20%	2.00%
Expected term (years)	'6 years 18 days	'6 years 1 month 24 days	'6 years 1 month 10 days

Unvested_Restricted_Stock_Unit

Unvested Restricted Stock Units Activity (Detail) (Restricted Stock Unit, 2012 Plan, USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock Unit | 2012 Plan	'	'
Number of shares	'	'
Beginning Balance	267,500	'
Granted	438,879	276,250
Vested	-128,136	-8,750
Forfeited	'	'
Ending Balance	578,243	267,500
Weighted Average Grant Date Fair Value	'	'
Beginning Balance	$9	'
Granted	$13.90	$9
Vested	$9.34	$9
Forfeited	'	'
Ending Balance	$12.65	$9

ShareBased_Compensation_Additi

Share-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended			12 Months Ended		1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Nov. 30, 2006	Oct. 31, 2012	Oct. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Oct. 31, 2012	Oct. 31, 2012
				2006 Plan	2012 Plan	ESPP	ESPP	ESPP	ESPP	ESPP
									On the grant date	On the last day of the offering period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'	'	'	'	'	'	'	'	'
Shares of common stock reserved	'	'	'	18,426,332	'	'	'	'	'	'
Term of stock options awarded	'	'	'	'10 years	'	'	'	'	'	'
Vesting period	'	'	'	'4 years	'4 years	'	'	'	'	'
Percentage of grant vesting on the first anniversary date	'	'	'	25.00%	25.00%	'	'	'	'	'
Authorized shares of common stock	'	'	'	'	4,200,000	2,000,000	'	'	'	'
Shares available for issuance under the 2006 Plan added to the shares reserved under the 2012 Plan	'	'	'	'	4,902,708	'	'	'	'	'
Term of stock options awarded	'	'	'	'	'10 years	'	'	'	'	'
Compensation cost for stock-based payment arrangements	$14,700,000	$6,758,000	$3,285,000	'	'	'	$338,000	$76,000	'	'
Unrecognized compensation costs related to unvested stock options and unvested restricted stock units issued	'	56,250,000	'	'	'	'	'	'	'	'
Remaining weighted-average period for unrecognized compensation costs	'0 years	'	'	'	'	'	'	'	'	'
Description	'	'	'	'	'	'The ESPP allows substantially all full-time and part-time employees to acquire shares of our common stock through payroll deductions over six month offering periods.	'	'	'	'
Per share purchase price as percentage of fair market value of a share of common stock	'	'	'	'	'	'	'	'	85.00%	85.00%
Purchases limit, percentage of employee's salary	'	'	'	'	'	15.00%	'	'	'	'
Maximum value of stock purchases per calendar year	'	'	'	'	'	25,000	'	'	'	'
Common stock issued	'	'	'	'	'	'	107,074	'	'	'
Weighted-average fair value of outstanding stock options	$5.88	$2.57	$1.29	'	'	'	'	'	'	'
Weighted-average fair value of the options granted	$9.48	$4.74	$2.43	'	'	'	'	'	'	'
Total intrinsic value of options exercised	41,793,000	1,472,000	2,230,000	'	'	'	'	'	'	'
Total intrinsic value of outstanding stock options	99,204,000	'	'	'	'	'	'	'	'	'
Total intrinsic value of exercisable stock options	$50,916,000	'	'	'	'	'	'	'	'	'

Employee_Benefits_Additional_I

Employee Benefits - Additional Information (Detail) (401 (k) retirement plan, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Cost of employer contributions to the plan	$2,488	$1,908	$1,624
Defined contribution plan, matching employer contribution percentage	100.00%	'	'
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	6.00%	'	'
Minimum	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Defined contribution plan, employees contribution percentage	1.00%	'	'
Maximum	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Defined contribution plan, employees contribution percentage	100.00%	'	'

Fair_Value_of_Financial_Assets

Fair Value of Financial Assets and Liabilities (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Total assets measured at fair value	$94,709	$35,023
Commercial paper	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	45,110	35,023
Money market funds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	911	'
Corporate bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	37,371	'
Municipal bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	10,819	'
Certificates of deposit	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	498	'
Fair Value, Inputs, Level 1	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Total assets measured at fair value	911	'
Fair Value, Inputs, Level 1 | Commercial paper	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 1 | Money market funds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	911	'
Fair Value, Inputs, Level 1 | Corporate bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 1 | Municipal bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 1 | Certificates of deposit	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 2	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Total assets measured at fair value	93,798	35,023
Fair Value, Inputs, Level 2 | Commercial paper	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	45,110	35,023
Fair Value, Inputs, Level 2 | Money market funds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 2 | Corporate bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	37,371	'
Fair Value, Inputs, Level 2 | Municipal bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	10,819	'
Fair Value, Inputs, Level 2 | Certificates of deposit	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	498	'
Fair Value, Inputs, Level 3	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Total assets measured at fair value	'	'
Fair Value, Inputs, Level 3 | Commercial paper	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 3 | Money market funds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 3 | Corporate bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 3 | Municipal bonds	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'
Fair Value, Inputs, Level 3 | Certificates of deposit	'	'
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]	'	'
Assets measured at fair value	'	'

Computation_of_Basic_and_Dilut

Computation of Basic and Diluted Net Income (Loss) Per Share Attributable to Common Stockholders (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net Income Loss Per Common Share [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net income (loss)	$53,206	$5,427	($2,065)	($4,117)	$4,080	$7,868	($6,898)	$18,453	$52,451	$23,503	($4,257)
Less:	'	'	'	'	'	'	'	'	'	'	'
Accretion of convertible redeemable preferred stock redemption premium	'	'	'	'	'	'	'	'	'	-9,378	-18,926
Accumulated accretion of beneficial conversion feature	'	'	'	'	'	'	'	'	'	-2,452	'
Net income allocable to convertible redeemable preferred stockholders	'	'	'	'	'	'	'	'	'	-5,504	'
Net income available (loss attributable) to common stock holders	'	'	'	'	'	'	'	'	52,451	6,169	-23,183
Less:	'	'	'	'	'	'	'	'	'	'	'
Change in fair value of warrant liabilities	'	'	'	'	'	'	'	'	'	-4,382	'
Accretion of convertible redeemable preferred stock redemption premium for shares assumed issued in exercise of warrants	'	'	'	'	'	'	'	'	'	-898	'
Plus:	'	'	'	'	'	'	'	'	'	'	'
Net income allocable to convertible redeemable preferred stockholders	'	'	'	'	'	'	'	'	'	-5,504	'
Diluted net income available (loss attributable) to common stockholders	'	'	'	'	'	'	'	'	52,451	5,333	-23,183
Denominator (basic):	'	'	'	'	'	'	'	'	'	'	'
Weighted average common shares outstanding	'	'	'	'	'	'	'	'	88,636,000	35,082,000	18,725,000
Denominator (diluted):	'	'	'	'	'	'	'	'	'	'	'
Weighted average common shares outstanding	'	'	'	'	'	'	'	'	88,636,000	35,082,000	18,725,000
Dilutive stock options and awards outstanding	'	'	'	'	'	'	'	'	4,991,320	4,088,101	'
Weighted average common shares from preferred stock	'	'	'	'	'	'	'	'	'	22,528,878	'
Weighted average common shares from warrants	'	'	'	'	'	'	'	'	2,318,422	491,860	'
Net weighted average common shares outstanding	'	'	'	'	'	'	'	'	95,946,000	62,191,000	18,725,000
Net income available (loss attributable) per share to common stockholders:	'	'	'	'	'	'	'	'	'	'	'
Basic	$0.58	$0.06	($0.02)	($0.05)	$0.01	$0.06	($0.56)	$0.34	$0.59	$0.18	($1.24)
Diluted	$0.54	$0.06	($0.02)	($0.05)	$0.01	($0.16)	($0.59)	$0.22	$0.55	$0.09	($1.24)
Convertible Redeemable Preferred Stockholders	'	'	'	'	'	'	'	'	'	'	'
Less:	'	'	'	'	'	'	'	'	'	'	'
Net income allocable to convertible redeemable preferred stockholders	'	'	'	'	'	'	'	'	'	4,444	'
Plus:	'	'	'	'	'	'	'	'	'	'	'
Net income allocable to convertible redeemable preferred stockholders	'	'	'	'	'	'	'	'	'	$4,444	'

Number_of_Outstanding_Stock_Op

Number of Outstanding Stock Options, Warrants to Purchase Common Preferred Stock and Convertible Redeemable Preferred Stock Excluded from Computation of Diluted Net Income (Loss) Per Share (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'	'
Common equivalent shares from stock warrants	2,318,422	491,860	'
Common shares from convertible redeemable preferred stock	'	22,528,878	'
Excluded From Earnings Per Share Calculation	'	'	'
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'	'
Stock options outstanding	4,315,153	'	2,551,074
Restricted stock units	45,673	'	'
Common equivalent shares from stock warrants	'	3,585,996	2,727,702
Common shares from convertible redeemable preferred stock	'	8,770,427	29,239,607
Antidilutive securities excluded from computation of earnings per share, amount, total	4,360,826	12,356,423	34,518,383

Components_of_Income_Tax_Provi

Components of Income Tax Provision (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current:	'	'	'
U.S. federal	$30	$388	$36
U.S. state and local taxes	58	67	178
Total current	88	455	214
Deferred:	'	'	'
U.S. federal	-36,631	-11,877	'
U.S. state and local taxes	-2,503	-2,308	'
Foreign	-63	'	'
Total deferred	($39,197)	($14,185)	'

Reconciliation_of_Income_Tax_a

Reconciliation of Income Tax at U.S. Statutory Rate to Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation Of Effective Income Tax Rate [Line Items]	'	'	'
Statutory federal income tax rate	35.00%	35.00%	34.00%
State tax expense, net of federal benefit	3.80%	6.10%	-4.50%
Nondeductible expense related to embedded derivative	0.00%	10.00%	0.00%
Other nondeductible expenses	6.20%	2.70%	-2.50%
Effect of change in income tax rates	-2.40%	14.40%	5.10%
Impact of state net operating losses	7.00%	-11.40%	15.50%
Other	0.00%	1.00%	0.60%
Expired net operating losses	16.30%	0.00%	0.00%
Reduction in valuation allowance due to business combination	0.00%	-145.10%	0.00%
Change in valuation allowance	-359.10%	-42.70%	24.10%
Total expense	-293.10%	-140.50%	-5.30%
Warrant	'	'	'
Reconciliation Of Effective Income Tax Rate [Line Items]	'	'	'
Nondeductible expense related, Share-based Compensation Cost	0.00%	-11.20%	-72.80%
Stock Options	'	'	'
Reconciliation Of Effective Income Tax Rate [Line Items]	'	'	'
Nondeductible expense related, Share-based Compensation Cost	0.10%	0.70%	-4.80%

Summary_of_Components_of_Defer

Summary of Components of Deferred Tax Assets and Liabilities (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred tax assets:	'	'
Net operating losses and credit carryforwards	$62,570	$62,307
Stock options	6,580	5,513
Deferred rent	1,692	196
Deferred revenue	13	44
Accrued expenses	795	1,310
Other	118	'
Total deferred tax assets	71,768	69,370
Valuation allowance	-1,229	-49,146
Net deferred tax assets	70,539	20,224
Deferred tax liabilities:	'	'
Property and equipment	-18,777	-20,012
Other	-627	-212
Total deferred tax liabilities	-19,404	-20,224
Net deferred tax assets	$51,135	'

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]	'	'	'
Increase (decrease) in valuation of allowance	($47,917)	($12,418)	($974)
Unrealized excess tax benefits from stock options exercised	14,821	1,845	'
Unrecognized tax benefit	393	393	0
Significant change in uncertain tax benefit reasonably possible amount of unrecorded benefit	0	'	'
Accrued interest or penalties	0	'	'
U.S. Federal	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards	199,408	'	'
Net operating loss carryforwards expiration date description	'expire in the years 2024 through 2033	'	'
U.S. Federal | Minimum	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards, expiration year	'2024	'	'
U.S. Federal | Maximum	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards, expiration year	'2033	'	'
State	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards	147,321	'	'
Net operating loss carryforwards expiration date description	'expire between 2014 and 2033	'	'
State | Minimum	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards, expiration year	'2014	'	'
Federal alternative tax credit carryover	$451	'	'
State | Maximum	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards, expiration year	'2033	'	'

Financial_Information_of_Segme

Financial Information of Segments (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenue	'	'	'	'	'	'	'	'	'	'	'
External customers	'	'	'	'	'	'	'	'	$369,658	$276,428	'
Income (loss) from operations	14,041	5,658	-2,191	-3,916	5,700	6,223	1,379	-209	13,592	13,093	4,843
Goodwill	156,120	'	'	'	129,428	'	'	'	156,120	129,428	'
Total assets	463,250	'	'	'	339,588	'	'	'	463,250	339,588	'
Consumer	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	'	'	'
External customers	'	'	'	'	'	'	'	'	340,121	254,678	'
Income (loss) from operations	'	'	'	'	'	'	'	'	23,997	18,840	'
Goodwill	96,583	'	'	'	69,891	'	'	'	96,583	69,891	'
Total assets	349,394	'	'	'	213,564	'	'	'	349,394	213,564	'
Enterprise	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	'	'	'
External customers	'	'	'	'	'	'	'	'	29,537	21,750	'
Intersegment revenue	'	'	'	'	'	'	'	'	5,316	3,506	'
Income (loss) from operations	'	'	'	'	'	'	'	'	-10,405	-5,747	'
Goodwill	59,537	'	'	'	59,537	'	'	'	59,537	59,537	'
Total assets	114,337	'	'	'	129,245	'	'	'	114,337	129,245	'
Eliminations	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	'	'	'
Intersegment revenue	'	'	'	'	'	'	'	'	-5,316	-3,506	'
Total assets	($481)	'	'	'	($3,221)	'	'	'	($481)	($3,221)	'

Segment_Reporting_Additional_I

Segment Reporting - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2013
	Segment
Segment Reporting Information [Line Items]	'
Number of reportable segments	2

Contingencies_Additional_Infor

Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2013
Contingencies [Line Items]	'	'
Value of the service guarantee	'	$1
Ownership Interest	'	7.50%
Shares Aquired As Damages	'	835
Complaint filed date	'September 2012	'
Name of defendant	'LifeLock, Inc and Todd Davis	'
Name of plaintiff	'Ms. Denise Richardson	'

Selected_Quarterly_Financial_D2

Selected Quarterly Financial Data - (unaudited) (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenue:	'	'	'	'	'	'	'	'	'	'	'
Consumer revenue	$94,068	$88,386	$82,574	$75,094	$70,775	$65,579	$61,616	$56,708	$340,121	$254,678	$193,949
Enterprise revenue	8,237	7,353	6,946	7,001	8,041	6,538	6,267	904	29,537	21,750	'
Total revenue	102,305	95,739	89,520	82,095	78,816	72,117	67,883	57,612	369,658	276,428	193,949
Gross profit	76,021	70,804	64,293	58,291	56,627	52,355	48,758	38,772	269,409	196,512	131,319
Income (loss) from operations	14,041	5,658	-2,191	-3,916	5,700	6,223	1,379	-209	13,592	13,093	4,843
Net income (loss)	$53,206	$5,427	($2,065)	($4,117)	$4,080	$7,868	($6,898)	$18,453	$52,451	$23,503	($4,257)
Basic	$0.58	$0.06	($0.02)	($0.05)	$0.01	$0.06	($0.56)	$0.34	$0.59	$0.18	($1.24)
Diluted	$0.54	$0.06	($0.02)	($0.05)	$0.01	($0.16)	($0.59)	$0.22	$0.55	$0.09	($1.24)

Valuation_And_Qualifying_Accou1

Valuation And Qualifying Accounts (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Allowance for Doubtful Accounts	'		'		'
Valuation And Qualifying Accounts Disclosure [Line Items]	'		'		'
Beginning Balance	$134	[1]	$88	[1]	$115	[1]
Additions (recoveries) –charged tocosts and expenses	114	[1]	79	[1]	-27	[1]
Deductions	-144	[1]	-33	[1]	'
Ending Balance	104	[1]	134	[1]	88	[1]
Valuation Allowance of Deferred Tax Assets	'		'		'
Valuation And Qualifying Accounts Disclosure [Line Items]	'		'		'
Beginning Balance	49,146	[2]	61,564	[2]	62,538	[2]
Additions (recoveries) –charged tocosts and expenses	-47,917	[2]	-12,418	[2]	-974	[2]
Ending Balance	$1,229	[2]	$49,146	[2]	$61,564	[2]
[1]	We record additions to the allowance for doubtful accounts based on historical collections, write-off experience, current economic trends, and changes in customer payment terms and other factors that may affect our ability to collect payments. Deductions principally reflect amounts charged off as uncollectible, less amounts recovered.
[2]	Deferred tax assets are reduced by a valuation allowance when, in our opinion, it is more likely than not that the related benefit will not be realized.