Intangible Assets, Net (Excluding Goodwill) [Abstract] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] 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] Proprietary data and models Noncompete Agreements [Member] Trademarks Proprietary Business Processes [Member] Developed technology Customer Relationships [Member] Customer relationships Trademarks [Member] Developed technology Developed Technology Rights [Member] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Carrying amount Finite-Lived Intangible Assets, Gross Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Total estimated future amortization expense Finite-Lived Intangible Assets, Net Intangible Assets, Net Intangible Assets Disclosure [Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Goodwill Schedule of Goodwill [Table Text Block] Stockholders Equity and Share-based Compensation [Abstract] Stockholders Equity and Share-based Compensation [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] Award Type [Domain] Equity Award [Domain] Vested and exercisable Vestedand Exercisable [Member] Vested and expected to vest Vestedand Expectedto Vest [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] Shares Available for Grant - Outstanding, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Number of Shares - Outstanding, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Weighted-Average Exercise Price - Outstanding, beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Shares Available for Grant - Shares authorized (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Number of Shares - Options exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Weighted Average Exercise Price - Options exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Shares Available for Grant - Options forfeited/canceled Shares Available for Grant - Options forfeited/canceled Shares Available for Grant - Options forfeited/canceled Number of Shares - Options forfeited/canceled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Weighted-Average Exercise Price - Options forfeited/canceled (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Share Available for Grant - Restricted stock units granted (in shares) Share Available for grant - Restricted stock units granted Share Available for grant - Restricted stock units granted Shares Available for Grant - Restricted stock units forfeited (in shares) Shares Available for Grant - Restricted stock units forfeited Shares Available for Grant - Restricted stock units forfeited Shares Available for Grant - Restricted stock units withheld related to net-share settlement of restricted stock units (in shares) Share Available for Grant - Restricted stock units withheld related to net-share settlement of restricted stock units Share Available for Grant - Restricted stock units withheld related to net-share settlement of restricted stock units Shares Available for Grant - Outstanding, ending balance (in shares) Number of Shares - Outstanding, ending balance (in shares) Weighted-Average Exercise Price - Outstanding, ending balance (in dollars per share) Outstanding (weighted-average contractual life) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Outstanding (intrinsic value) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Vested and exercisable (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Vested and exercisable (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price Vested and exercisable (weighted-average contractual life) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Vested and exercisable (intrinsic value) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Vested and expected to vest (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Vested and expected to vest (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Vested and expected to vest (weighted-average contractual life) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Vested and expected to vest (intrinsic value) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Segment Reporting [Abstract] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES Japan JAPAN Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Long-lived assets Long-Lived Assets Property, Plant and Equipment, Net, by Type [Abstract] Property and Equipment, Net Property, Plant and Equipment Disclosure [Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Statement of Cash Flows [Abstract] Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Net Income (Loss) Attributable to Parent 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] Stock-based compensation Depreciation, Depletion and Amortization Stock-based compensation Share-based Compensation Excess tax benefit from stock-based compensation Excess Tax Benefit from Share-based Compensation, Operating Activities (Gain) loss on sale of patent assets, net Gain (Loss) on Disposition of Other Assets Amortization of premium on investments Accretion (Amortization) of Discounts and Premiums, Investments Deferred taxes Deferred Income Tax Expense (Benefit) Other Other Noncash Income (Expense) Changes in assets and liabilities: Payments to Acquire Businesses, Net of Cash Acquired [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Other receivables Increase (Decrease) in Other Receivables Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued and other liabilities Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Investing activities Additional Cash Flow Elements, Investing Activities [Abstract] Purchases of investments Payments to Acquire Available-for-sale Securities Maturities of investments Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Sales of investments Proceeds from Sale of Available-for-sale Securities Business acquisition, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Increase in restricted cash Increase (Decrease) in Restricted Cash Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Acquisitions of patent assets Payments to Acquire Other Productive Assets Proceeds from sale of patent assets Proceeds from Sale of Intangible Assets Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Proceeds from Deferred Payment Obligations Proceeds from Deferred Payment Obligations Proceeds from Deferred Payment Obligations Financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from exercise of stock options and other common stock issuances Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Taxes paid related to net-share settlements of restricted stock units Payments Related to Tax Withholding for Share-based Compensation Excess tax benefit from stock-based compensation Excess Tax Benefit from Share-based Compensation, Financing Activities Payments for Repurchase of Common Stock Payments for Repurchase of Common Stock Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net increase in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Non-cash investing and financing activities Noncash Investing and Financing Items [Abstract] Change in patent assets purchased and accrued but not paid Change in patent assets purchased and accrued but not paid. Change in fixed assets purchased and accrued but not paid Capital Expenditures Incurred but Not yet Paid Change in other assets purchased and accrued but not paid Change in other assets purchased and accrued but not paid Unpaid cash consideration for business acquisition Business Combination, Cash Consideration Not Yet Paid and Equity Interests Issued and Issuable Business Combination, Cash Consideration Not Yet Paid and Equity Interests Issued and Issuable Noncash or Part Noncash Acquisition, Debt Assumed Noncash or Part Noncash Acquisition, Debt Assumed 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, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] 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] Finance Assets Measured At Fair Value On A Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Number of reportable segments Number of Reportable Segments Statement of Comprehensive Income [Abstract] Net income Net Income (Loss) Available to Common Stockholders, Basic Other comprehensive income, net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Unrealized gains (losses) on available-for-sale securities: Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract] Unrealized holding gains (losses) arising during the period Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Less: reclassification adjustment for (gains) losses included in net income Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Net unrealized gains (losses) on available-for-sale securities, net of tax Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Patent Assets, Net [Abstract] Patent Assets, Net PatentAssetsTextBlock [Table Text Block] Patent assets. Organization, Consolidation and Presentation of Financial Statements [Abstract] Nature Of Business Nature of Operations [Text Block] Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Amortization of intangible assets Amortization of Intangible Assets Goodwill [Roll Forward] Goodwill [Roll Forward] Balance as of December 31, 2013 Goodwill Goodwill from business acquisition Goodwill, Acquired During Period Balance as of September 30, 2014 Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Stock options Employee Stock Option [Member] Performance-based restricted stock units with a market condition Performance Shares [Member] Dividend Yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Risk-free rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, type [Axis] Property, Plant and Equipment, Type [Axis] Property and equipment, type [Domain] Property, Plant and Equipment, Type [Domain] Internal-use software Software Development [Member] Leasehold improvements Leasehold Improvements [Member] Computer, equipment and software Computer Equipment [Member] Furniture and fixtures Furniture and Fixtures [Member] Construction-in-progress Asset under Construction [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Internal-use software Capitalized Computer Software, Gross Leasehold improvements Leasehold Improvements, Gross Computer, equipment and software Machinery and Equipment, Gross Furniture and fixtures Furniture and Fixtures, Gross Construction-in-progress Construction in Progress, Gross Total property and equipment, gross Property, Plant and Equipment, Gross Less: Accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Total property and equipment, net Property, Plant and Equipment, Net Patent Assets, Net ScheduleofPatentAssetsTableTextBlock [Table Text Block] -- None. No documentation exists for this element. -- Expected Future Annual Amortization Of Patent Assets Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Commitments and Contingencies Disclosure [Abstract] Commitments And Contingencies Commitments and Contingencies Disclosure [Text Block] Goodwill Goodwill Disclosure [Text Block] Financial Instruments, Entities that Calculate Net Asset Value Per Share [Table] Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Table] 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] Commercial paper Commercial Paper [Member] Municipal bonds Municipal Bonds [Member] Money market funds Money Market Funds [Member] U.S. government and agency securities US Government Corporations and Agencies Securities [Member] Instrument Type [Axis] Investment Type [Axis] Instrument [Domain] Investments [Domain] Corporate bonds Corporate Bond Securities [Member] Equity securities Equity Securities [Member] Liability Class [Axis] Liability Class [Axis] Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Deferred Payment Obligations Other Debt Obligations [Member] Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] Amortized Cost Available-for-sale Securities, Amortized Cost Basis Unrealized Gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Unrealized Losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Estimated Fair Value Available-for-sale Securities Cash equivalents Cash equivalents [Abstract] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Short-term investments Short-term Investments [Abstract] Short-term investments Investments, Fair Value Disclosure Debt Instrument, Fair Value Disclosure Debt Instrument, Fair Value Disclosure Financial and Nonfinancial Liabilities, Fair Value Disclosure Financial and Nonfinancial Liabilities, Fair Value Disclosure Statement of Financial Position [Abstract] Assets Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Short-term investments Short-term Investments Restricted cash Restricted Cash and Cash Equivalents, Current Accounts receivable Accounts Receivable, Gross, Current Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Deferred tax assets Deferred Tax Assets, Gross, Current Total current assets Assets, Current Patent assets, net Patent assets, net Carrying amount of finite-lived patent assets after accumulated amortization as of the balance sheet date of the costs pertaining to the exclusive legal rights granted to the owner to exploit an invention or a process for a period of time specified by law. Such costs may have been expended to directly apply and receive patent rights, or to acquire such rights. Property and equipment, net Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Goodwill Restricted cash, less current portion Restricted Cash and Cash Equivalents, Noncurrent Deferred Tax Assets, Net, Noncurrent Deferred Tax Assets, Net, Noncurrent Other 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 liabilities Accrued Liabilities, Current Deferred revenue Deferred Revenue, Current Deferred payment obligations Other Long-term Debt, Current Other current liabilities Other Liabilities, Current Total current liabilities Liabilities, Current Deferred revenue, less current portion Deferred Revenue, Noncurrent Deferred tax liabilities Noncurrent Deferred Tax Liabilities Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdictionto which the entity is obligated to pay income tax, as well as the noncurrent portion of the amount recognized for unceratin tax position as of the balance sheet date. Other liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 9) Commitments and Contingencies Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Common stock Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders’ equity Liabilities and Equity Subscription fee revenue from related party transaction Related Party Transaction, Amounts of Transaction Receivables due from related parties Accounts Receivable, Related Parties, Current Stock Repurchase [Abstract] Stock Repurchase [Abstract] Repurchase of shares of common stock Stock Repurchased and Retired During Period, Shares Balance as of March 31, 2015 Share Repurchase Utilized Share Repurchase Utilized to date Balance as of January 1, 2015 Stock Repurchased, Accumulated, Weighted Average Price Stock Repurchased, Accumulated, Weighted Average Price Repurchase of shares of common stock Stock Repurchased During Period Weighted Average Price Stock Repurchased During the Period Weighted Average Price per Share Balance as of March 31, 2015 Balance as of January 1, 2015 Stock Repurchased, Accumulated Value Stock Repurchased, Accumulated Value Repurchase of shares of common stock Stock Repurchased During Period, Value Balance as of March 31, 2015 Authorized share repurchases Stock Repurchase Program, Authorized Amount Activity Under Equity Settled Award Plans And Related Information Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Restricted Stock Unit Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Weighted-Average Assumptions Used To Estimate The Fair Value Of PBRSUs Schedule of Assumptions Used [Table Text Block] Schedule of Repurchase Agreements Schedule of Repurchase Agreements [Table Text Block] Investment Holdings [Table] Investment Holdings [Table] Municipal bonds Investment Holdings [Line Items] Investment Holdings [Line Items] Amortized Cost Unrealized Gains Available-for-sale Securities, Gross Unrealized Gain Unrealized Losses Available-for-sale Securities, Gross Unrealized Loss Earnings Per Share [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] Weighted-average anti-dilutive securities [Domain] Antidilutive Securities, Name [Domain] Stock options outstanding Restricted stock units outstanding Restricted Stock [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: Weighted-average: [Abstract] Weighted-average anti-dilutive securities Weighted-Average Anti-Dilutive Securities Weighted-average anti-dilutive securities not included in the calculation for diluted shares outstanding Summary Of Investments In Available-For-Sale Securities Available-for-sale Securities [Table Text Block] Statement [Table] Statement [Table] Patents Patents [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Asset, Useful Life Finite-Lived Intangible Asset, Useful Life Finite-lived Intangible Assets [Roll Forward] Finite-lived Intangible Assets [Roll Forward] Patent assets, beginning balance Patent assets - Additions Patent assets - Sales Reclassify patent assets to assets held-for-sale Reclassify patent assets to assets held-for-sale Patent assets, ending balance Accumulated amortization, beginning balance Accumulated amortization - Additions Accumulated amortization - Sales Reclassify accumulated amortization related to patent assets Reclassify accumulated amortization related to patent assets Accumulated amortization, ending balance Patent assets, net Net income available to common stockholders: Net income available to common stockholders: [Abstract]0 Numerator: Numerator: [Abstract] Allocation of net income to participating stockholders Undistributed Earnings (Loss) Allocated to Participating Securities, Basic Net income available to common stockholders Denominator: Denominator: [Abstract] Basic shares: Basic shares: [Abstract] Weighted-average shares used in computing basic net income per common share Weighted Average Number of Shares Outstanding, Basic Diluted shares: Diluted shares: [Abstract] Dilutive effect of stock options and restricted stock units using the treasury-stock method Weighted Average Number Diluted Shares Outstanding Adjustment Weighted-average shares used in computing diluted net income per common share Weighted Average Number of Shares Outstanding, Diluted Net income per common share: Net income per share: [Abstract] Basic (dollars per common share) Earnings Per Share, Basic Diluted (dollars per common share) Earnings Per Share, Diluted Payables and Accruals [Abstract] Fair Value Inputs, Liabilities, Quantitative Information [Table] Fair Value Inputs, Liabilities, Quantitative Information [Table] Accrued payroll-related expenses Accrued Payroll Related Expenses [Member] Accrued expenses Accrued Liabilities [Member] Fair Value Inputs, Liabilities, Quantitative Information [Line Items] Fair Value Inputs, Liabilities, Quantitative Information [Line Items] Revenue By Location Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block] Long-Lived Assets Information By Location Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block] Property And Equipment, Net Property, Plant and Equipment [Table Text Block] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2011 Plan 2011 Plan [Member] 2011 Plan [Member] Restricted stock Additional shares of common stock reserved for issuance under the 2011 Plan (in shares) Aggregate intrinsic value of stock options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Total fair value of stock options vested Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Total fair value of RSUs vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Shares withheld for tax withholdings (in shares) Shares Paid for Tax Withholding for Share Based Compensation Total payments for the employees’ minimum tax obligations to taxing authorities PBRSUs granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Stock-based compensation expense Allocated Share-based Compensation Expense Unrecognized compensation cost related to unvested equity awards Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Weighted-average service period of unrecognized compensation cost related to unvested equity awards Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Accrued And Other Current Liabilities Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Basic and Diluted Net Income Per Share Available To Common Stockholders Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Anti-Dilutive Securities Not Included In Diluted Shares Outstanding Calculation Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Intangible Assets Net Intangible Assets Net [Member] Intangible Assets, Net Schedule of Finite-Lived Intangible Assets [Table Text Block] Expected Future Annual Amortization Of Intangible Assets Net Income Available to Common Stockholders Earnings Per Share [Text Block] Level 3 Interest and Other Income Interest and Other Income Rent expense related to non-cancelable operating leases net of sublease income Operating Leases, Rent Expense, Net Sublease income Operating Leases, Rent Expense, Sublease Rentals Loss Contingency, Number of Defendants Loss Contingency, Number of Defendants Debt Instrument, Repayable Upon Redemption, Preferred Stock Debt Instrument, Repayable Upon Redemption, Preferred Stock Debt Instrument, Repayable Upon Redemption, Preferred Stock Number of active insurance policies Number of Active Insurance Policies The number of active insurance policies as of the Company's balance sheet date. Reserves for known and incurred but not reported claims Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount Effective tax rate Effective Income Tax Rate Reconciliation, Percent Segment Reporting Segment Reporting Disclosure [Text Block] Restricted stock units granted Restricted Stock Units Granted [Member] Restricted stock units vested Restricted Stock Units Vested [Member] Restricted stock units forfeited Restricted Stock Units Forfeited [Member] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Non-vested units, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Non-vested units, 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 shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 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 shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period 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 shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period 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 Non-vested units, ending balance (in shares) Non-vested units, ending balance (in dollars per share) Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested, intrinsic value Aggregate Instrinsic Value of Non-Vested Restricted Stock Units Share Based Compensation Arrangement by Share Based Payment Award, Equity Instruments Other Than Options, Outstanding, Intrinsic Value 2015 (remainder) Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year 2016 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2017 Finite-Lived Intangible Assets, Amortization Expense, Year Three Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Other Other Country [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] United States Country of Domicile Percent of Total Revenue Country Of Domicile Percent Of Total Revenue Other foreign country Foreign Country Percent of Total Revenue Foreign Country Percent Of Total Revenue Total revenue Revenues Total revenue Percent of Total Revenue Percent of Total Revenue Short-term Investments Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Weighted Average Weighted Average [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Subsidiaries [Member] Subsidiaries [Member] The Sellers [Member] The Sellers [Member] The Sellers [Member] Finite-lived Intangible Assets Acquired Finite-lived Intangible Assets Acquired Accumulated amortization - Additions Contributions to Escrow Deposit Contributions to Escrow Deposit Contributions to Escrow Deposit Number of Companies Involved in Syndicate Number of Companies Involved in Syndicate Number of Companies Involved in Syndicate Accounting Policies [Abstract] Basis Of Presentation And Significant Accounting Policies Significant Accounting Policies [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Property and equipment, types Property, Plant and Equipment, Other Types [Member] Depreciation and amortization expense Document and Entity Information [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Entity Trading Symbol Trading Symbol 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 Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding 2015 2016 2017 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2018 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Accrued And Other Current Liabilities Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] Income Statement [Abstract] Revenue Cost of revenue Cost of Revenue Selling, general and administrative expenses Selling, General and Administrative Expense Operating income Operating Income (Loss) Other income, net Income before provision for income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Net income Net income available to common stockholders Net income per common share: Net income per common share: [Abstract] Weighted-average shares used in computing net income per common share: Weighted-average shares used in computing net income per common share: [Abstract] Basic (in shares) Diluted (in shares)