Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Stock Options and PSOs Employee Stock Options And Performance Stock Options [Member] Employee Stock Options And Performance Stock Options [Member] PSOs Performance Stock Option [Member] Performance Stock Option [Member] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2019 and 2018 Performance Metric Granted in 2017 2019 and 2018 Performance Metric Granted in 2017 [Member] 2019 and 2018 Performance Metric Granted in 2017 [Member] 2019 Performance Metric, Targeted Free Cash Flow Performance Metric 2019 Performance Metric, Targeted Free Cash Flow Performance Metric [Member] 2019 Performance Metric, Targeted Free Cash Flow Performance Metric [Member] 2019 Performance Metric, Adjusted Gross Margin Target 2019 Performance Metric, Adjusted Gross Margin Target [Member] 2019 Performance Metric, Adjusted Gross Margin Target [Member] 2017 Performance Metric, Targeted Free Cash Flow Performance Metric 2017 Performance Metric, Targeted Free Cash Flow Performance Metric [Member] 2017 Performance Metric, Targeted Free Cash Flow Performance Metric [Member] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Vesting Tranche One Share-based Compensation Award, Tranche One [Member] Vesting Tranche Two Share-based Compensation Award, Tranche Two [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Options outstanding, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Options granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Options exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Options cancelled/forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Options outstanding, ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Options outstanding, weighted average exercise price, beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Options granted, weighted average exercise price (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Options exercised, weighted average exercise price (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Options cancelled/forfeited, weighted average exercise price (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Options outstanding, weighted average exercise price, ending balance (in dollars per share) Weighted average remaining contractual life, in years Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Percent of targeted awards that will vest Share-based Compensation Arrangements by Share-based Payment Award, Vesting Percent Of Awards Granted Share-based Compensation Arrangements by Share-based Payment Award, Vesting Percent Of Awards Granted Percent of targeted performance metric Share-based Compensation Arrangements by Share-based Payment Award, Percent Of Award Target Performance Metric Share-based Compensation Arrangements by Share-based Payment Award, Percent Of Award Target Performance Metric Share-based compensation options vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Percent of achievement of award target performance metric Share-based Compensation Arrangements by Share-based Payment Award, Percent Of Achievement Of Award Target Performance Metric Share-based Compensation Arrangements by Share-based Payment Award, Percent Of Achievement Of Award Target Performance Metric Stock-based compensation expense Allocated Share-based Compensation Expense Leases [Abstract] Leases Lessee, Operating Leases [Text Block] Fair Value Disclosures [Abstract] Investment Securities and Fair Value Measurements Investment Securities And Fair Value Measurements, Disclosure [Text Block] Investment Securities And Fair Value Measurements, Disclosure [Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Corporate bonds Corporate Bond Securities [Member] Agency securities Agency Securities [Member] Certificates of deposit Certificates of Deposit [Member] Treasury securities US Treasury Securities [Member] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Gross Realized Gains Debt Securities, Available-for-sale, Realized Gain Gross Realized Losses Debt Securities, Available-for-sale, Realized Loss Gross Proceeds from Sales Proceeds from Sale of Debt Securities, Available-for-sale Gross Proceeds from Maturities Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Accretion (amortization) of discounts and premiums Accretion (Amortization) of Discounts and Premiums, Investments Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Dynasty Marketplace, Inc. Dynasty Marketplace, Inc. [Member] Dynasty Marketplace, Inc. [Member] WegoWise, Inc. WegoWise, Inc. [Member] WegoWise, Inc. [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Technology Software Development [Member] Customer relationships Customer Relationships [Member] Database Database Rights [Member] Trademark and trade name Trademarks and Trade Names [Member] Non-compete agreements Noncompete Agreements [Member] Backlog Order or Production Backlog [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Consideration total, gross Business Combination, Consideration Total Prior To Adjustments Business Combination, Consideration Total Prior To Adjustments Escrow consideration Business Combination, Consideration Transferred, Escrow Amount Business Combination, Consideration Transferred, Escrow Amount Net tangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Identified intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Goodwill Goodwill Other noncurrent assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Purchase consideration, paid in cash Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Estimated Useful Life (in years) Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Accrued and other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities Deferred tax liability, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Total liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Purchase consideration Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Acquisition related expenses Business Acquisition, Transaction Costs Revenue from acquiree Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual Net income (loss) from acquiree Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual Research and Development [Abstract] 2019 Capitalized Computer Software, Amortization Expense, Remainder of Fiscal Year Capitalized Computer Software, Amortization Expense, Remainder of Fiscal Year 2020 Capitalized Computer Software, Amortization Expense, Year Two Capitalized Computer Software, Amortization Expense, Year Two 2021 Capitalized Computer Software, Amortization Expense, Year Three Capitalized Computer Software, Amortization Expense, Year Three 2022 Capitalized Computer Software, Amortization Expense, Year Four Capitalized Computer Software, Amortization Expense, Year Four Internal use software development costs, net Capitalized Computer Software, Net Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Debt Disclosure [Abstract] Summary of Long-term Debt Schedule of Long-term Debt Instruments [Table Text Block] Schedule of Principal payments for Term Loan Schedule of Maturities of Long-term Debt [Table Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Other current liabilities Other Current Liabilities [Member] Other current assets Other Current Assets [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Per incident policy limit Property, Liability And Casualty Insurance, Per Incident And Per Residence Coverage Limit Property, Liability And Casualty Insurance, Per Incident And Per Residence Coverage Limit Quota share of tenant liability insurance provided, percent Reinsurance Retention Policy, Reinsured Risk, Percentage Liability for reported claims and claims incurred but not reported Liability for Claims and Claims Adjustment Expense, Property Casualty Liability Deposits held with a third party related to insurance services collateral Property, Liability And Casualty Insurance, Deposits Held With Third Party As Collateral For Services Property, Liability And Casualty Insurance, Deposits Held With Third Party As Collateral For Services Document and Entity Information [Abstract] Document and Entity Information [Abstract] Document Information [Table] Document Information [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Class A common stock Common Class A [Member] Class B common stock Common Class B [Member] Document Information [Line Items] Document Information [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity emerging growth company Entity Emerging Growth Company Entity small business Entity Small Business Statement of Financial Position [Abstract] Statement [Table] Statement [Table] Statement [Line Items] Statement [Line Items] Assets Assets [Abstract] Current assets Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Investment securities—current Debt Securities, Available-for-sale, Current Accounts receivable, net Accounts Receivable, Net, Current Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Investment securities—noncurrent Debt Securities, Available-for-sale, Noncurrent Property and equipment, net Property, Plant and Equipment, Net Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Capitalized software, net Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Other long-term assets Other Assets, Noncurrent Total assets Assets Liabilities and Stockholders’ Equity Liabilities and Equity [Abstract] Current liabilities Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued employee expenses Employee-related Liabilities, Current Accrued expenses Accrued Liabilities, Current Deferred revenue Contract with Customer, Liability, Current Other current liabilities Other Liabilities, Current Long-term debt, net—current portion Long-term Debt, Current Maturities Total current liabilities Liabilities, Current Operating lease liabilities Operating Lease, Liability, Noncurrent Long-term debt, net Long-term Debt, Excluding Current Maturities Other long-term liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 9) Commitments and Contingencies Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.0001 par value, 25,000 authorized and no shares issued and outstanding at March 31, 2019 and December 31, 2018 Preferred Stock, Value, Issued Common stock Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Treasury stock, at cost, 370 Class A shares at March 31, 2019 and December 31, 2018 Treasury Stock, Value Accumulated deficit Retained Earnings (Accumulated Deficit) Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders’ equity Liabilities and Equity Internal-Use Software Development Costs Research, Development, and Computer Software Disclosure [Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Credit Facility Line of Credit [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Term Loan Secured Debt [Member] Revolving Credit Facility Revolving Credit Facility [Member] Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] Wells Fargo Wells Fargo Bank, N.A [Member] Wells Fargo Bank, N.A [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] Federal Funds Rate Federal Funds Effective Swap Rate [Member] LIBOR London Interbank Offered Rate (LIBOR) [Member] Other Assets Other Assets [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Principal amounts due under term loan Long-term Debt, Gross Less: Debt financing costs Debt Issuance Costs, Net Long-term debt, net of unamortized debt financing costs Long-term Debt Long-term debt - current portion Long-term Debt, Fiscal Year Maturity [Abstract] Long-term Debt, Fiscal Year Maturity [Abstract] 2019 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2020 Long-term Debt, Maturities, Repayments of Principal in Year Two 2021 Long-term Debt, Maturities, Repayments of Principal in Year Three 2022 Long-term Debt, Maturities, Repayments of Principal in Year Four 2023 Long-term Debt, Maturities, Repayments of Principal in Year Five Principal amounts due under term loan Line of credit, amount outstanding Long-term Line of Credit Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity EBITDA to interest expense ratio Long-term Debt, Covenant Restrictions, EBITDA To Interest Expense Ratio Long-term Debt, Covenant Restrictions, EBITDA To Interest Expense Ratio Funded indebtedness to EBITDA ratio Long-term Debt, Covenant Restrictions, Funded Indebtedness To EBITDA Ratio Long-term Debt, Covenant Restrictions, Funded Indebtedness To EBITDA Ratio Annual decrease in required leverage ratio Long-term Debt, Covenant Restrictions, Annual Decrease In Required Leverage Ratio Long-term Debt, Covenant Restrictions, Annual Decrease In Required Leverage Ratio Required leverage ratio Long-term Debt, Covenant Restrictions, Required Leverage Ratio Long-term Debt, Covenant Restrictions, Required Leverage Ratio Floor plus 20% of the sum of the combined outstanding principal amounts Long-term Debt, Covenant Restrictions, Floor Plus 20 Percent Of The Sum Of the Combined Outstanding Principal Amounts Long-term Debt, Covenant Restrictions, Floor Plus 20 Percent Of The Sum Of the Combined Outstanding Principal Amounts Acquisition purchase price floor for 0.5 increase in required leverage ratio for 12 month period following the close date Long-term Debt, Covenant Restrictions, Acquisition Purchase Price Floor For 0.5 Increase In Required Leverage Ratio For 12 Month Period Following The Close Date Long-term Debt, Covenant Restrictions, Acquisition Purchase Price Floor For 0.5 Increase In Required Leverage Ratio For 12 Month Period Following The Close Date Variable rate, basis spread percent Debt Instrument, Basis Spread on Variable Rate Average interest rate Debt Instrument, Interest Rate During Period Commitment fee percentage Line of Credit Facility, Commitment Fee Percentage Commitment fee, usage threshold for 37.5 basis points commitment fee, percentage Long-term Debt, Commitment Fee, Usage Threshold For 37.5 Basis Points Commitment Fee, Percentage Long-term Debt, Commitment Fee, Usage Threshold For 37.5 Basis Points Commitment Fee, Percentage Unused portion of the Revolving Facility, percentage Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Capitalized deferred financing costs Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Amortization of deferred debt financing costs Amortization Internal use software development costs, gross Capitalized Computer Software, Gross Less: Accumulated amortization Capitalized Computer Software, Accumulated Amortization Capitalized software development costs during the period Capitalized Computer Software, Additions Amortization expense with respect to software development costs during the period Capitalized Computer Software, Amortization Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] 215-221 Rose Avenue, Venice, California 215-221 Rose Avenue, Venice, California [Member] 215-221 Rose Avenue, Venice, California Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Square feet of leased area Lessee, Operating Lease, Square Feet Of Leased Area Lessee, Operating Lease, Square Feet Of Leased Area Lease term Lessee, Operating Lease, Term of Contract Operating lease liabilities Operating Lease, Liability Accounting Policies [Abstract] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] PSUs and PSOs Performance Shares [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Weighted average common shares outstanding (in shares) Weighted Average Number of Shares Issued, Basic Less: Weighted average unvested restricted shares subject to repurchase (in shares) Weighted Average Number of Shares, Restricted Stock Weighted average common shares outstanding; basic (in shares) Weighted Average Number of Shares Outstanding, Basic Plus: Weighted average options, restricted stock units and restricted shares used to compute diluted net income per common share (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted average common shares outstanding; diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Shares excluded from net loss per share attributable to common stockholders (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Income Tax Disclosure [Abstract] Income tax expense Income Tax Expense (Benefit) Deferred tax liabilities acquired through Dynasty acquisition Effective Income Tax Rate Reconciliation, Deferred Tax Liabilities Acquired Through Business Acquisition Effective Income Tax Rate Reconciliation, Deferred Tax Liabilities Acquired Through Business Acquisition Pre-tax income Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Effective tax rate Effective Income Tax Rate Reconciliation, Percent Statement of Stockholders' Equity [Abstract] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common stock Common Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Treasury Stock Treasury Stock [Member] Accumulated Deficit Retained Earnings [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance Beginning balance (in shares) Shares, Outstanding Exercise of stock options Stock Issued During Period, Value, Stock Options Exercised Exercise of stock options (in shares) Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Vesting of restricted stock units, net of shares withheld for taxes Restricted Stock Units, Value, Shares Issued Net Of Tax Withholdings Restricted Stock Units, Value, Shares Issued Net Of Tax Withholdings Vesting of restricted stock units, net of shares withheld for taxes (in shares) Restricted Stock Units, Shares Issued Net Of Shares For Tax Withholdings Restricted Stock Units, Shares Issued Net Of Shares For Tax Withholdings Vesting of early exercised shares Adjustments to Additional Paid in Capital, Share-based Compensation and Exercise of Stock Options Conversion of Class B stock to Class A stock Conversion of Stock, Amount Converted Conversion of Class B stock to Class A stock (in shares) Conversion of Stock, Shares Converted Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Cumulative-effect adjustment resulting from adoption of ASU 2014-09 Cumulative Effect of New Accounting Principle in Period of Adoption Net income Net Income (Loss) Attributable to Parent Ending balance Ending balance (in shares) Equity [Abstract] Share Repurchase Program Stockholders' Equity Note Disclosure [Text Block] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair value, recurring measurements Fair Value, Measurements, Recurring [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 Fair Value, Inputs, Level 1 [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Money market funds Money Market Funds [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Estimated Fair Value Debt Securities, Available-for-sale Total Assets, Fair Value Disclosure Subsequent Events Subsequent Events [Text Block] Statement of Comprehensive Income [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Changes in unrealized gains (losses) on investment securities Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Available-for-sale Securities, Amortized Cost Basis [Abstract] (Deprecated 2018-01-31) Debt Securities, Available-for-sale [Abstract] Total available-for-sale investment securities Debt Securities, Available-for-sale, Amortized Cost Gross Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Maximum contractual maturity period Available-For-Sale Securities, Maximum Contractual Maturity Available-For-Sale Securities, Maximum Contractual Maturity Schedule of Capitalized Computer Software Schedule Of Capitalized Computer Software [Table Text Block] Schedule Of Capitalized Computer Software [Table Text Block] Schedule of Capitalized Computer Software Future Amortization Expense Schedule Of Capitalized Computer Software, Future Amortization Expense [Table Text Block] Schedule of Capitalized Computer Software, Future Amortization Expense [Table Text Block] Preferred stock, par value (usd per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Preferred stock, shares outstanding Preferred Stock, Shares Outstanding Common stock, par value (usd per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Common stock, shares outstanding Common Stock, Shares, Outstanding Treasury stock (in shares) Treasury Stock, Shares Statement of Cash Flows [Abstract] Restricted cash included in other assets Restricted Cash, Noncurrent Total cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Basis of Presentation and Significant Accounting Policies Basis of Accounting, Policy [Policy Text Block] Leases Lessee, Leases [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Segment Reporting [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Core solutions Core Solutions [Member] Core Solutions [Member] Value plus services Value Plus Services [Member] Value Plus Services [Member] Other Other Services [Member] Other Services [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Revenue Revenue from Contract with Customer, Excluding Assessed Tax Revenue recognized in deferred revenue Contract with Customer, Liability, Revenue Recognized Schedule of Purchase Price Allocation Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Pro Forma Information Business Acquisition, Pro Forma Information [Table Text Block] Business Combinations Business Combination Disclosure [Text Block] Income Statement [Abstract] Costs and operating expenses: Costs and Expenses [Abstract] Cost of revenue (exclusive of depreciation and amortization) Cost of Goods and Services Sold Sales and marketing Selling and Marketing Expense Research and product development Research and Development Expense General and administrative General and Administrative Expense Depreciation and amortization Depreciation, Depletion and Amortization Total costs and operating expenses Costs and Expenses Income (loss) from operations Operating Income (Loss) Other expense, net Other Nonoperating Income (Expense) Interest income (expense), net Interest Income (Expense), Net Income (loss) before provision for (benefit from) income taxes Provision for (benefit from) income taxes Net income Net income per common share: Earnings Per Share [Abstract] Basic (in dollars per share) Earnings Per Share, Basic Diluted (in dollars per share) Earnings Per Share, Diluted Weighted average common shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Diluted (in shares) RSUs and PSUs Restricted Stock Units And Performance Stock Units [Member] Restricted Stock Units And Performance Stock Units [Member] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] PSUs Performance Stock Units [Member] Performance Stock Units [Member] PSUs Granted in 2018 Performance Stock Units Granted in 2018 [Member] Performance Stock Units Granted in 2018 [Member] PSUs Granted in 2017 Performance Stock Units Granted in 2017 [Member] Performance Stock Units Granted in 2017 PSUs Granted in 2019 Performance Stock Units Granted in 2019 [Member] Performance Stock Units Granted in 2019 [Member] 2017 Performance Metric 2017 Performance Metric [Member] 2017 Performance Metric [Member] 2016 Performance Metric 2016 Performance Metric [Member] 2016 Performance Metric [Member] Shares granted in period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Performance based cash bonus payment percent Share-based Compensation Arrangements by Share-based Payment Award, Performance Based Cash Bonus Payment, Percent Share-based Compensation Arrangements by Share-based Payment Award, Performance Based Cash Bonus Payment, Percent Share-based compensation options vested in period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Percent of cash bonus payments on initial targets, percent Share-Based Compensation Arrangements By Share-Based Payment Award, Percent Of Cash Bonus Payment On Initial Targets Share-Based Compensation Arrangements By Share-Based Payment Award, Percent Of Cash Bonus Payment On Initial Targets Remaining stock-based compensation expense for unvested shares, not yet recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options Stock-based compensation expense, weighted average recognition period Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Remaining stock-based compensation expense for unvested options, not yet recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options Goodwill and Intangible Assets Disclosure [Abstract] Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] 2019 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Net Carrying Value Finite-Lived Intangible Assets, Net Income Taxes Income Tax Disclosure [Text Block] Revenue and Other Information Revenue from Contract with Customer [Text Block] Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] 130 Castilian Drive Santa Barbara, California 130 Castilian Drive Santa Barbara, California [Member] 130 Castilian Drive Santa Barbara, California [Member] 9201 Spectrum Center Boulevard in San Diego, California 9201 Spectrum Center Boulevard In San Diego, California [Member] 9201 Spectrum Center Boulevard In San Diego, California [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Lease, Cost [Abstract] Lease, Cost [Abstract] Operating lease cost Operating Lease, Cost Assets and Liabilities, Lessee [Abstract] Assets and Liabilities, Lessee [Abstract] Other current liabilities Operating Lease, Liability, Current Total operating lease liabilities Weighted-average remaining lease term (years) Operating Lease, Weighted Average Remaining Lease Term Weighted-average discount rate Operating Lease, Weighted Average Discount Rate, Percent Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases Operating Lease, Payments Operating Lease Liabilities, Payments Due [Abstract] Operating Lease Liabilities, Payments Due [Abstract] 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total future minimum lease payments Lessee, Operating Lease, Liability, Payments, Due Less: imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 2019 Operating Leases, Future Minimum Payments, Remainder of Fiscal Year 2020 Operating Leases, Future Minimum Payments, Due in Two Years 2021 Operating Leases, Future Minimum Payments, Due in Three Years 2022 Operating Leases, Future Minimum Payments, Due in Four Years 2023 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total lease commitments Operating Leases, Future Minimum Payments Due Liabilities for additional leases that have not yet commenced Operating Lease Liability, Lease Not Yet Commenced Operating Lease Liability, Lease Not Yet Commenced Lease not yet commenced, term Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract Stock-Based Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASU 2016-02 Accounting Standards Update 2016-02 [Member] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Unvested, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Vested (in shares) Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Unvested, ending balance (in shares) Weighted- Average Grant Date Fair Value per Share Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Unvested, beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Vested (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Unvested, ending balance (in dollars per share) Schedule of Weighted Average Number of Shares Schedule of Weighted Average Number of Shares [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Schedule of Impact of Adoption of New Revenue Standard Impact on Financial Statements Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Revenue Business Acquisition, Pro Forma Revenue Net income (loss) Business Acquisition, Pro Forma Net Income (Loss) Net income (loss) per common share: Business Acquisition, Pro Forma Information [Abstract] Basic (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Basic Diluted (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Diluted Unvested restricted stock units Contingent restricted stock units Fixed Price Restricted Stock Unit [Member] Fixed Price Restricted Stock Unit [Member] Shares excluded from net income (loss) per common share (in shares) Cash from operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization, Excluding Amortization of Financing Costs Depreciation, Depletion and Amortization, Excluding Amortization of Financing Costs Stock-based compensation Share-based Compensation Deferred income taxes Deferred Income Taxes and Tax Credits Other Other Noncash Income (Expense) Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Other long-term assets Increase (Decrease) in Other Operating Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued employee expenses Increase (Decrease) in Employee Related Liabilities Accrued expenses Increase (Decrease) in Other Accrued Liabilities Deferred revenue Increase (Decrease) in Contract with Customer, Liability Other long-term liabilities Increase (Decrease) in Other Operating Liabilities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash from investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Additions to capitalized software Payments to Develop Software Purchases of investment securities Payments to Acquire Debt Securities, Available-for-sale Sales of investment securities Maturities of investment securities Acquisition, net of cash acquired Payments to Acquire Businesses, Gross Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash from financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from stock option exercises Proceeds from Stock Options Exercised Tax withholding for net share settlement Payments Related to Tax Withholding for Share-based Compensation Proceeds from issuance of debt Proceeds from Issuance of Secured Debt Principal payments on debt Repayments of Secured Debt Payment of debt issuance costs Payments of Debt Issuance Costs Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Net decrease in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect Cash, cash equivalents and restricted cash Cash and Cash Equivalents, at Carrying Value [Abstract] Beginning of period End of period Noncash investing and financing activities Noncash Investing and Financing Items [Abstract] Purchases of property and equipment included in accounts payable and accrued expenses Capital Expenditures Incurred but Not yet Paid Additions of capitalized software included in accrued and accrued employee expenses Capitalized Computer Software Additions, Incurred But Not Yet Paid Capitalized Computer Software Additions, Incurred But Not Yet Paid Stock-based compensation capitalized for software development Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount Tax withholding for net share settlement included in accrued employee expenses Tax Withholding For Share Based Compensation Incurred But Not Yet Paid Tax Withholding For Share Based Compensation Incurred But Not Yet Paid Purchase consideration for acquisitions included in other current liabilities Business Combination, Consideration Accrued But Not Yet Paid Business Combination, Consideration Accrued But Not Yet Paid Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Database Database [Member] Database [Member] Technology Technology [Member] Technology [Member] Partner relationships Partner Relationships [Member] Partner Relationships [Member] Domain names Internet Domain Names [Member] Patents Patents [Member] Weighted average Weighted Average [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Gross Carrying Value Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Weighted Average Useful Life in Years Finite-Lived Intangible Asset, Useful Life Amortization expense Amortization of Intangible Assets Available-for-sale Securities, Debt Maturities [Abstract] Available-for-sale Securities, Debt Maturities [Abstract] Amortized Cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract] Due in 1 year or less Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost Due after 1 year through 3 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost Estimated Fair Value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract] Due in one year or less Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Due after one year through three years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value Total available-for-sale investment securities Goodwill [Roll Forward] Goodwill [Roll Forward] Goodwill at December 31, 2018 Goodwill from acquisition of Dynasty Goodwill, Acquired During Period Goodwill at March 31, 2019 Summary of Stock Option Activity Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Restricted Stock Units Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Schedule of Restricted Stock Awards Activity Nonvested Restricted Stock Shares Activity [Table Text Block] Schedule of Finite-Lived Intangible Assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Schedule of Goodwill Schedule of Goodwill [Table Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Nature of Business Nature of Operations [Text Block] Schedule of Available-for-sale Securities Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Available-for-sale Investments, by Remaining Contract Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Schedule of Sales, Calls, and Maturities Schedule of Realized Gain (Loss) [Table Text Block] Fair Value, Assets Measured on Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Long-Term Debt Long-term Debt [Text Block] Share repurchase program, authorized amount Stock Repurchase Program, Authorized Amount Restricted Stock Awards Restricted Stock [Member] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Employee Employee [Member] Employee [Member] Non-Employee Director Non-Employee Director [Member] Non-Employee Director [Member] Weighted Average Grant Date Fair Value per Share Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Schedule of Components of Lease Expense Lease, Cost [Table Text Block] Schedule of Minimum Lease Payments Under Leases Lessee, Operating Lease, Liability, Maturity [Table Text Block] Summary of Future Minimum Payments for Obligations Lessee, Operating Lease, Disclosure [Table Text Block] Intangible Assets and Goodwill Goodwill and Intangible Assets Disclosure [Text Block] Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Schedule of Product Information by Revenue Categories Disaggregation of Revenue [Table Text Block]