Document And Entity Information
Scanner Appliances and Other Computer Equipment Subject To Subscription [Member]
Represents information related to scanner appliances and other computer equipment subject to subscription.
Dividend yield
us-gaap_DerivativeNotionalAmount
Derivative, Notional Amount
Scanner Appliances and Other Computer Equipment Not Placed In Service [Member]
Represents scanner appliances and other computer equipment not placed in service.
Note To Financial Statement Details Textual
Purchased Intangible Assets
qlys_DepreciationDepletionAndAmortizationExcludingIntangibleAssetAmortization
Depreciation, Depletion And Amortization, Excluding Intangible Asset Amortization
Represents amount of depreciation, depletion and amortization excluding intangible asset amortization.
Significant Accounting Policies
Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]
Note 2 - Fair Value of Financial Instruments
Scanner Appliances [Member]
Represents information related to scanner appliances.
Hedging Relationship [Domain]
Note 3 - Accumulated Other Comprehensive Income
Risk-free interest rate
Note 4 - Property and Equipment, Net
Cash Flow Hedging [Member]
Note 5 - Revenue from Contracts with Customers
Contract With Customer, Commission Asset Balances [Table Text Block]
Tabular disclosure of commission asset balance of contract with customer.
Spell Security [Member]
Represents information related to spell security.
Note 6 - Acquisitions
Not Designated as Hedging Instrument [Member]
Note 7 - Intangible Assets, Net
Available-for-sale Securities, Debt and Equity Maturities, Year One through Two, Fair Value
Represents fair value of debt maturities for available-for-sale securities through year one to year two.
Note 8 - Leases
Note 9 - Commitment and Contingencies
us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax
Total change in unrealized gain on marketable securities, net of tax
Available-for-sale Securities, Debt and Equity Maturities, Year over two years, Fair Value
Represents fair value of available-for-sale for debt maturities after year two.
Hedging Relationship [Axis]
Income Tax Disclosure [Text Block]
Note 10 - Stockholders' Equity and Stock-based Compensation
Accumulated Other Comprehensive Income Disclosure [Text Block]
The entire note disclosure of accumulated other comprehensive income.
Note 12 - Income Taxes
Change in net unrealized gain (loss), net of tax effect of ($128), ($243) and $0 in fiscal years 2020, 2019 and 2018, respectively
Hedging Designation [Axis]
Note 13 - Segment Information and Information about Geographic Area
Hedging Designation [Domain]
Note 14 - Net Income Per Share
Volatility
Designated as Hedging Instrument [Member]
Note 15 - Selected Quarterly Financial Information (Unaudited)
us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax
Reclassification adjustment for net (gain) loss realized and included in net income, net of tax effect of $6, $0 and $0 in fiscal years 2020, 2019 and 2018
us-gaap_LiabilitiesCurrent
Total current liabilities
Available-for-sale Securities, Debt and Equity Maturities, Next Twelve Months, Fair Value
Represents fair value of available-for-sale securities for debt maturities for next twelve months.
Note 2 - Fair Value of Financial Instruments - Cash and Cash Equivalents (Details)
Note 2 - Fair Value of Financial Instruments - Fair Value Hierarchy (Details)
Note 2 - Fair Value of Financial Instruments - Summary of the Fair Value of Marketable Securities (Details)
Expected term (in years) (Year)
Asset-backed Securities [Member]
Note 2 - Fair Value of Financial Instruments - Summary of Derivative Financial Instruments (Details)
Note 2 - Fair Value of Financial Instruments - Amounts Recognized In Statement Of Operations (Details)
Note 3 - Accumulated Other Comprehensive Income - Accumulated Other Comprehensive Income (Loss) (Details)
Purchase Consideration
Business Combination, Consideration Transferred, Total
Note 3 - Accumulated Other Comprehensive Income - Amounts Reclassified from AOCI (Details)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value
Note 4 - Property and Equipment, Net - Property and Equipment, Net (Details)
us-gaap_FinitelivedIntangibleAssetsAcquired1
Finite-lived Intangible Assets Acquired
Time based Shared Based Compensation [Member]
Represents information related to time based share based compensation.
Note 5 - Revenue from Contracts with Customers - Expected Revenue from All Remaining Performance Obligations (Details)
us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)
qlys_SharebasedCompensationTerminationPeriodTrigger
Share-based Compensation Termination Period Trigger (Month)
Represents termination period trigger for share-based compensation.
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Note 5 - Revenue from Contracts with Customers - Expected Revenue from All Remaining Performance Obligations 2 (Details)
us-gaap_BusinessCombinationConsiderationTransferredOther1
Business Combination, Consideration Transferred, Other
qlys_SharebasedCompensationPercentageOfSharesThatWillVestUponTrigger
Share-Based Compensation, Percentage Of Shares That Will Vest Upon Trigger
Represents percentage of shares that will vest upon trigger for share-based compensation.
Note 5 - Revenue from Contracts with Customers - Revenue by Sales Channel (Details)
qlys_SharebasedCompensationPercentageOfAwardsBasedOnAchievementOfPerformanceGoals
Share-Based Compensation, Percentage Of Awards Based On Achievement Of Performance Goals
Represents percentage of awards based on achievement of performance goals for share-based compensation.
Note 5 - Revenue from Contracts with Customers - Capitalized Cost to Obtain Contracts, Current and Noncurrent (Details)
Note 6 - Acquisitions - Estimated Fair Values of the Acquired Assets (Details)
Note 6 - Acquisitions - Changes in Carrying Amount of Goodwill (Details)
Share-based Payment Arrangement, Option, Activity [Table Text Block]
Note 7 - Intangible Assets, Net - Carrying Value of Intangible Assets (Details)
Note 7 - Intangible Assets, Net - Expected Amortization Expense in Future Periods (Details)
Expected to vest, weighted average grant date fair value (in dollars per share)
Represents weighted average exercise for share-based compensation arrangement by share-based payment award for equity instruments other than options, expected to vest.
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Granted, weighted average grant date fair value (in dollars per share)
Note 8 - Leases - Lease-related Assets and Liabilities (Details)
us-gaap_DerivativeNumberOfInstrumentsHeld
Derivative, Number of Instruments Held, Total
qlys_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsTargetNumberOfShares
Share-Based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Target Number Of Shares (in shares)
Represents target number of shares of share-based compensation by share-based payment award for equity instruments other than options.
Vested, weighted average grant date fair value (in dollars per share)
Sales and maturities of marketable securities
Note 8 - Leases - Supplemental Cash Flow Information (Details)
qlys_GoodwillDeductibleForTaxPurposePeriod
Goodwill, Deductible for Tax Purpose Period (Year)
Represents deductible for tax purpose period for goodwill.
Note 8 - Leases - Minimum Annual Lease Payments (Details)
Cancelled, weighted average grant date fair value (in dollars per share)
Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
Balance, weighted average grant date fair value (in dollars per share)
Balance, weighted average grant date fair value (in dollars per share)
Note 8 - Leases - Weighted Average Remaining Lease Term and Weighted Average Discount Rate (Details)
Note 9 - Commitment and Contingencies - Remaining Purchase Commitments (Details)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Cancelled, number of shares (in shares)
qlys_ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPeriodNumberOfQuarterlyPeriods
Share based Compensation Arrangement by Share based Payment Award, Vesting Period, Number Of Quarterly Periods
Represents number of quarterly periods for vesting periods for share based compensation arrangement by share based payment award.
Note 10 - Stockholders' Equity and Stock-based Compensation - Reserved Shares of Common Stock for Future Issuance (Details)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Balance, number of shares (in shares)
Balance, number of shares (in shares)
Other foreign currency transaction gains (losses)
Note 10 - Stockholders' Equity and Stock-based Compensation - Summary of Stock-based Compensation Expense (Details)
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
qlys_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodAsAPercentageOfTarget
Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period As A Percentage Of Target
Represents equity instruments other than options vested in period as a percentage of target for share-based compensation arrangement by share-based payment award.
Note 10 - Stockholders' Equity and Stock-based Compensation - Fair Value Assumptions, Stock Options (Details)
Schedule of Derivative Instruments [Table Text Block]
qlys_PaymentsToAcquirePrivatelyheldInvestments
Purchase of privately-held investment
Represents cash outflows to acquire privately-held investments.
Note 10 - Stockholders' Equity and Stock-based Compensation - Share-based Compensation and Stock Options Activity (Details)
Exercisable, weighted average remaining contractual life (Year)
Note 10 - Stockholders' Equity and Stock-based Compensation - Summarizes the Outstanding and Vested Stock Options (Details)
US Government Agencies Debt Securities [Member]
Note 10 - Stockholders' Equity and Stock-based Compensation - Share-based Compensation, Restricted Stock and Restricted Stock Units (Details)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Granted, number of shares (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)
Vested, number of shares (in shares)
Note 12 - Income Taxes - Schedule of Income before Income Tax, Domestic and Foreign (Details)
Corporate Debt Securities [Member]
Vested and Expected to vest, weighted average remaining contractual life (Year)
Intangible Assets Not Subject to Amortization [Member]
Represents intangible assets not subject to amortization.
Note 12 - Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details)
Exercisable (in shares)
Note 12 - Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)
Exercisable, Weighted average exercise price (in dollars per share)
Note 12 - Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details)
Exercisable, aggregate intrinsic value
Note 12 - Income Taxes - Schedule of Unrecognized Tax Benefits Roll Forward (Details)
Note 13 - Segment Information and Information about Geographic Area - Revenue and Property and Equipment, Net by Geographic Area (Details)
Vested and expected to vest (in shares)
Note 14 - Net Income Per Share - Basic and Diluted Net Income Per Share (Details)
Vested and Expected to vest, weighted average exercise price (in dollars per share)
Note 14 - Net Income Per Share - Anti-dilutive Net Income Per Share (Details)
Vested and Expected to vest, aggregate intrinsic value
Note 15 - Selected Quarterly Financial Information (Unaudited) - Schedule of Quarterly Financial Information (Details)
Notes To Financial Statements
Notes To Financial Statements [Abstract]
Foreign Exchange Contract [Member]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value
Weighted Average Remaining Contractual Life Balance (Year)
Aggregate intrinsic value
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)
Cash and Cash Equivalents and Debt Securities, Available-for-sale, Amortized Cost to Fair Value [Table Text Block]
Tabular disclosure of cash and cash equivalents and debt securities available-for-sale amortized cost to fair value.
Lessee, Operating Leases and Finance Lease [Text Block]
The entire disclosure of operating lease and finance lease for lessee.
Short-term marketable securities, amortization cost
Represents current amortized cost basis for available-for-sale debt.
us-gaap_PaymentsToAcquireMarketableSecurities
Purchases of marketable securities
Financial Instruments [Domain]
qlys_AvailableforsaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxCurrent
Short-term marketable securities, unrealized loss
Represents accumulated unrealized loss before tax current for available for sale debt securities.
qlys_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxNoncurrent
Long-term marketable securities, unrealized loss
Represents accumulated gross unrealized loss before tax noncurrent for debt securities available for sale.
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Weighted average exercise price, balance (in dollars per share)
Weighted average exercise price, balance (in dollars per share)
Cash and cash equivalents and short-term and long-term Marketable Securities, fair value
Represents fair value disclosure for cash and cash equivalents and short-term and long-term debt securities available for sale.
Long-term marketable securities, amortization cost
Represents noncurrent amortized cost basis for available for sale debt securities.
Cash and cash equivalents and marketable securities, amortization cost
Represents amortized cost of cash and cash equivalents and available-for-sale debt securities.
Deferred revenues, current
Unrealized gains, short-term securities
Represents accumulated gross unrealized gain before tax current for debt securities available for sale.
Weighted average exercise price, canceled (in dollars per share)
Financial Instrument [Axis]
Unrealized gains, long-term securities
Represents unrealized gain before tax for non current debt securities available for sale.
Schedule of Goodwill [Table Text Block]
Weighted average exercise price, granted (in dollars per share)
Weighted average exercise price, exercised (in dollars per share)
Accrued liabilities
Accounts payable
Equity Incentive Plan (in shares)
Balance (in shares)
Balance (in shares)
Retirement Plan Type [Axis]
Retirement Plan Type [Domain]
Purchases of property and equipment recorded in accounts payable and accrued liabilities
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod
Canceled (in shares)
Proceeds from disposal of property and equipment
us-gaap_PolicyTextBlockAbstract
Accounting Policies
Shares available for future grants under an equity incentive plan (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)
Restricted stock units (in shares)
Indefinite-lived Intangible Assets [Axis]
Indefinite-lived Intangible Assets, Major Class Name [Domain]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanModificationIncrementalCompensationCost
Share-based Payment Arrangement, Plan Modification, Incremental Cost
us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Purchases of property and equipment
Common stock options (in shares)
Non-cash investing and financing activities
us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)
Weighted average shares used in computing net income per share:
Noncompete Agreements [Member]
Cash paid for income taxes, net of refunds
us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage
Current liabilities:
Developed Technology Rights [Member]
Vesting [Axis]
Vesting [Domain]
Supplemental disclosures of cash flow information
us-gaap_Assets
Total assets
Patents [Member]
Plan Name [Axis]
Shareholders' Equity and Share-based Payments [Text Block]
Plan Name [Domain]
Compensation and Employee Benefit Plans [Text Block]
us-gaap_OperatingLeaseExpense
Operating Lease, Expense
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)
us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense
Share-based Payment Arrangement, Expense, Tax Benefit
Computer Software, Intangible Asset [Member]
Deferred tax assets, net
Finite-Lived Intangible Assets by Major Class [Axis]
Finite-Lived Intangible Assets, Major Class Name [Domain]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]
us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation
Taxes related to net share settlement of equity awards
Award Type [Domain]
Basis of Presentation and Significant Accounting Policies [Text Block]
Award Type [Axis]
Net income
Net income
us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Amortization of intangible assets
Net Book Value
Total expected future amortization expense
Intangible assets, net
Restricted Stock Units (RSUs) [Member]
Cost
Performance Shares [Member]
Share-based Payment Arrangement, Option [Member]
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]
us-gaap_CapitalizedComputerSoftwareGross
Capitalized Computer Software, Gross
Antidilutive Securities [Axis]
Adjustment
Antidilutive Securities, Name [Domain]
Goodwill acquired
Intangible assets not subject to amortization
Commitments and Contingencies Disclosure [Text Block]
Business Combination Disclosure [Text Block]
us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Less: accumulated depreciation and amortization
Property and equipment, net
Property, Plant and Equipment, Net, Ending Balance
Property and equipment, net
Schedule of Business Acquisitions, by Acquisition [Table Text Block]
Goodwill
Balance
Balance
us-gaap_PropertyPlantAndEquipmentGross
Property and equipment
Net gains (losses) from forward contracts
us-gaap_Investments
Investments, Total
Derivative Instrument [Axis]
Derivative Contract [Domain]
Cash flows from investing activities:
Debt Securities, Available-for-sale
Net income per share:
Earnings Per Share [Text Block]
Income before income taxes
Income before income taxes
Total
us-gaap_IncreaseDecreaseInAccruedLiabilities
Accrued liabilities
Provision for (benefit from) income taxes
Total provision for (benefit from) provision for income taxes
us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax
Cash flow hedges, change in net unrealized gain (loss), tax
Cash flow hedges, reclassification adjustment for net gain realized and included in net income, tax
us-gaap_ForeignCurrencyCashFlowHedgeGainLossToBeReclassifiedDuringNext12Months
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months
us-gaap_IncreaseDecreaseInAccountsPayable
Accounts payable
Available-for-sale debt securities, reclassification adjustment for net (gain) loss realized and included in net income, tax
qlys_CapitalizedComputerSoftwareUnamortized
Capitalized Computer Software, Unamortized
Represents unamortized capitalized computer software.
us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesBeforeReclassificationAdjustmentsTax
Available-for-sale debt securities, change in net unrealized gain (loss), tax
us-gaap_OperatingExpenses
Total operating expenses
Restricted cash
us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Defined Contribution Plan, Employer Discretionary Contribution Amount
us-gaap_RestrictedCash
Restricted Cash, Total
General and administrative
Cash and cash equivalents
Cash, Cash Equivalents and Short-Term and Long-Term Investments Policy [Policy Text Block]
Accounting policies disclosure for cash, cash equivalent and short-term and long-term investments.
us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities
Other noncurrent liabilities
Stock-based compensation
us-gaap_AllocatedShareBasedCompensationExpense
Share-based Payment Arrangement, Expense
U.S. government agencies
Commercial paper
Money market funds
Asset-backed securities
Amendment Flag
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive income
City Area Code
Use of Estimates, Policy [Policy Text Block]
Total
New Accounting Pronouncements, Policy [Policy Text Block]
qlys_SharebasedCompensationArrangementBySharebasedPaymentAwardNumberOfSharesAuthorizedAnnualIncreasePercentOfSharesOutstanding
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized, Annual Increase, Percent of Shares Outstanding
Represents percentage of shares outstanding for member of shares authorized for shared-based compensation arrangement by share-based compensation.
qlys_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardStrikePriceAsAPercentageOfMarketValue
Share-based Compensation Arrangement by Share-based Payment Award, Award Strike Price as a Percentage of Market Value
Represents awards strike price as a percentage for share based compensation arrangement by share based payment award.
us-gaap_GainLossOnSaleOfPropertyPlantEquipment
Loss on disposal of property and equipment
INDIA
us-gaap_IncreaseDecreaseInContractWithCustomerLiability
Deferred revenues
us-gaap_SharesOutstanding
Balances (in shares)
Balances (in shares)
Foreign government agencies
Common stock, shares outstanding (in shares)
Corporate bonds
Preferred stock, shares outstanding (in shares)
Preferred Stock, Shares Outstanding, Ending Balance (in shares)
qlys_SharebasedCompensationArrangementBySharebasedPaymentAwardNumberOfSharesAuthorizedAnnualIncreaseShares
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized, Annual Increase, Shares (in shares)
Represents number of shares authorized for share-based compensation arrangement by share-based compensation.
Current Fiscal Year End Date
us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets
Prepaid expenses and other assets
Operating leases, weighted average discount rates
Document Fiscal Period Focus
Document Fiscal Year Focus
Document Period End Date
Lease liabilities arising from obtaining right of use assets
us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability
Operating leases, weighted average remaining lease term (Year)
Entity File Number
Entity Emerging Growth Company
Schedule of Shares Reserved for Future Issuance [Table Text Block]
Tabular disclosure of shares reserved for future issuance.
Document Type
Entity Small Business
Entity Shell Company
Document Information [Line Items]
Document Information [Table]
Entity Public Float
Entity Filer Category
Entity Current Reporting Status
Entity Voluntary Filers
Entity Well-known Seasoned Issuer
us-gaap_ImpairmentOfLongLivedAssetsHeldForUse
Impairment of Long-Lived Assets Held-for-use
us-gaap_GoodwillImpairmentLoss
Goodwill, Impairment Loss
us-gaap_CapitalizedContractCostImpairmentLoss
Capitalized Contract Cost, Impairment Loss
us-gaap_IncreaseDecreaseInAccountsReceivable
Accounts receivable
Stock-based compensation
Quarterly Financial Information [Text Block]
Entity Tax Identification Number
Entity Central Index Key
Entity Registrant Name
Entity [Domain]
Legal Entity [Axis]
Entity Address, Address Line One
us-gaap_AmortizationOfIntangibleAssets
Amortization of Intangible Assets, Total
Entity Address, City or Town
us-gaap_AmortizationOfDeferredSalesCommissions
Amortization of Deferred Sales Commissions
Entity Address, Postal Zip Code
Entity Address, State or Province
Allowance for doubtful accounts receivable
us-gaap_StockRepurchasedDuringPeriodShares
Repurchase of common stock (in shares)
Entity Common Stock, Shares Outstanding
us-gaap_StockRepurchasedAndRetiredDuringPeriodValue
Stock Repurchased and Retired During Period, Value
us-gaap_StockRepurchasedAndRetiredDuringPeriodShares
Stock Repurchased and Retired During Period, Shares (in shares)
us-gaap_StockRepurchasedDuringPeriodValue
Repurchase of common stock
us-gaap_AdvertisingExpense
Advertising Expense
Investments [Domain]
Trading Symbol
Investment Type [Axis]
Local Phone Number
Issuance of common stock upon exercise of stock options (in shares)
Exercised (in shares)
us-gaap_TableTextBlock
Notes Tables
qlys_DeferredLiabilitiesRightofuseAssets
Operating leases - right of use asset
Represents the deferred liabilities right-of-use-assets.
Issuance of common stock upon exercise of stock options
qlys_DeferredTaxLiabilitiesDeferredCommission
Deferred commissions
Represents the deferred tax liabilities deferred commission.
Bad debt expense
qlys_StockRepurchaseProgramAdditionalAuthorizedAmount
Stock Repurchase Program, Additional Authorized Amount
Amount of additional stock repurchase plan authorized.
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Granted (in shares)
Sales and marketing
us-gaap_LiabilitiesAndStockholdersEquity
Total liabilities and stockholders’ equity
UNITED STATES
Provident Fund Plan and Gratuity Plan [Member]
Represents the provident fund plan and gratuity plan
Exercise Price Range One [Member]
Represents the exercise price range one.
Research and development
Retained earnings
Exercise Price Range Two [Member]
Represents the exercise price range two.
Accumulated other comprehensive income (loss)
Money Market Funds [Member]
401(k) Plan [Member]
Represents a 401(k) Plan.
Exercise Price Range Seven [Member]
Represents exercise price range seven.
Exercise Price Range Eight [Member]
Represents the exercise price range eight.
Cash and Cash Equivalents [Axis]
Derivative Instruments, Gain (Loss) [Table Text Block]
Exercise Price Range Nine [Member]
Represents exercise price range nine.
us-gaap_InterestExpense
Interest expense
Cash and Cash Equivalents [Domain]
Exercise Price Range Ten [Member]
Represents exercise price range ten.
Cash [Member]
Exercise Price Range Three [Member]
Represents the exercise price range three.
Exercise Price Range Four [Member]
Represents the exercise price range four.
Changes in operating assets and liabilities:
Exercise Price Range Five [Member]
Represents the exercise price range five.
Exercise Price Range Six[Member]
Represents exercise price range six.
Layered Insights [Member]
Represents the layered insights.
qlys_BusinessCombinationEarnoutMilestone
Business Combination, Earnout Milestone
Represents the earnout milestone under business combination.
us-gaap_DisclosureTextBlockAbstract
Notes to Financial Statements
The 1Mobility [Member]
Represents the acquisition of 1Mobility.
Subsequent Event [Member]
Lease obligations, noncurrent, operating leases
Operating lease liabilities, noncurrent
us-gaap_ForeignCurrencyTransactionGainBeforeTax
Foreign Currency Transaction Gain, before Tax
us-gaap_ForeignCurrencyTransactionLossBeforeTax
Foreign Currency Transaction Loss, before Tax
qlys_BusinessCombinationAdditionalConsideration
Business Combination, Additional Consideration
Represents the additional consideration under business combinations.
us-gaap_OperatingLeaseLiability
Present value of minimum payments, operating leases
Deferred income taxes
Securities Owned Not Readily Marketable, Policy [Policy Text Block]
Subsequent Event Type [Axis]
Less: lease obligations, current, operating leases
Operating lease liabilities, current
Operating lease liabilities, current
Subsequent Event Type [Domain]
us-gaap_FinanceLeaseLiabilityCurrent
Accrued liabilities
Other noncurrent liabilities
us-gaap_FinanceLeaseLiabilityNoncurrent
Operating leases - right of use asset
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue
Total minimum lease payments, operating leases
us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount
Less: amount representing interest, operating leases
us-gaap_DeferredIncomeTaxExpenseBenefit
Total deferred (benefit) provision
2023, operating leases
2024, operating leases
2025, operating leases
us-gaap_FinanceLeaseRightOfUseAsset
Property and equipment, net
2025 and thereafter, operating leases
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
2022
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
2023
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
2024
2021, operating leases
2022, operating leases
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths
2021
Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block]
Equity-Based Arrangements, Individual Contracts, Type of Deferred Compensation [Domain]
Foreign Currency Transactions and Translations Policy [Policy Text Block]
Commission asset, noncurrent
us-gaap_ShareBasedCompensation
Stock-based compensation
Other noncurrent assets
Lessee, Leases [Policy Text Block]
Weighted Average Remaining Life (Year)
Business Combinations Policy [Policy Text Block]
Weighted Average Life (Year)
Finite-Lived Intangible Asset, Useful Life (Year)
Equity-Based Arrangements, Individual Contracts, Type of Deferred Compensation [Axis]
Earnings Per Share, Policy [Policy Text Block]
us-gaap_Revenues
Revenues
Operating expenses:
Comprehensive Income, Policy [Policy Text Block]
Income Tax, Policy [Policy Text Block]
us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments
Amortization of premiums and (accretion of discounts) on marketable securities
Research, Development, and Computer Software, Policy [Policy Text Block]
us-gaap_LesseeOperatingLeaseRenewalTerm
Lessee, Operating Lease, Renewal Term (Year)
Long-term marketable securities
Depreciation and amortization expense
us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Taxes related to net share settlement of equity awards (in shares)
Intangible Assets Disclosure [Text Block]
us-gaap_ForeignCurrencyContractAssetFairValueDisclosure
Foreign currency forward contracts
us-gaap_ForeignCurrencyContractsLiabilityFairValueDisclosure
Foreign currency forward contracts
us-gaap_AssetsCurrent
Total current assets
us-gaap_CashAndCashEquivalentsFairValueDisclosure
Cash and cash equivalents
Share-based Payment Arrangement [Policy Text Block]
us-gaap_InvestmentsFairValueDisclosure
Investments, Fair Value Disclosure, Total
Business acquisitions recorded in accrued liabilities and deferred tax liability
us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill
Impairment of Intangible Assets (Excluding Goodwill), Total
us-gaap_ImpairmentOfInvestments
Other than Temporary Impairment Losses, Investments, Total
Advertising Cost [Policy Text Block]
Common stock, $0.001 par value; 1,000,000,000 shares authorized, 39,252,665 and 39,146,272 shares issued and outstanding at December 31, 2020 and 2019, respectively
Adjustments to reconcile net income to net cash provided by operating activities:
Measurement Frequency [Axis]
Measurement Frequency [Domain]
Fair Value, Recurring [Member]
Common stock, shares authorized (in shares)
Commercial Paper [Member]
Common stock, shares issued (in shares)
Common stock, par or stated value per share (in dollars per share)
us-gaap_DeferredTaxAssetsValuationAllowance
Deferred Tax Assets, Valuation Allowance, Total
Valuation allowance
Total shares reserved for future issuance (in shares)
Statistical Measurement [Domain]
Operating cash flows included in the measurement of lease liabilities
us-gaap_OperatingLeasePayments
Maximum [Member]
Minimum [Member]
Commission asset, current
us-gaap_DeferredTaxAssetsNet
Net deferred tax assets
Statistical Measurement [Axis]
Preferred stock: $0.001 par value; 20,000,000 shares authorized, no shares issued and outstanding at December 31, 2020 and 2019
us-gaap_NumberOfReportingUnits
Number of Reporting Units
us-gaap_DeferredTaxAssetsLiabilitiesNet
Net deferred tax assets
Preferred stock, shares issued (in shares)
Preferred Stock, Shares Issued, Total (in shares)
Cash paid for interest expense
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]
Other
Property, Plant and Equipment Disclosure [Text Block]
Geographical [Axis]
Goodwill and Intangible Assets, Policy [Policy Text Block]
Property, Plant and Equipment [Table Text Block]
Geographical [Domain]
us-gaap_DeferredTaxAssetsGross
Gross deferred tax assets
Preferred stock, shares authorized (in shares)
Preferred Stock, Shares Authorized (in shares)
us-gaap_DeferredIncomeTaxLiabilities
Total deferred tax liabilities
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]
Preferred stock, par value (in dollars per share)
Preferred Stock, Par or Stated Value Per Share (in dollars per share)
Fair Value, Inputs, Level 3 [Member]
Total foreign exchange gains (losses), net
Deferred revenues
Fair Value Hierarchy and NAV [Domain]
Fair Value, Inputs, Level 1 [Member]
Intangible assets
Fair Value, Inputs, Level 2 [Member]
Fair Value Hierarchy and NAV [Axis]
us-gaap_ProceedsFromDividendsReceived
Proceeds from Dividends Received
us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities
Accrued liabilities
Cumulative Effect, Period of Adoption [Domain]
Cumulative Effect, Period of Adoption [Axis]
us-gaap_PropertyPlantAndEquipmentUsefulLife
Property, Plant and Equipment, Useful Life (Year)
Cumulative Effect, Period of Adoption, Adjustment [Member]
Cash flows from operating activities:
Assets Held under Capital Leases [Member]
Revenue [Policy Text Block]
Statement [Line Items]
us-gaap_NumberOfOperatingSegments
Number of Operating Segments
Accounts receivable, net of allowance of $725 and $585 at December 31, 2020 and 2019, respectively
Furniture and Fixtures [Member]
us-gaap_NumberOfReportableSegments
Number of Reportable Segments
Additional paid-in capital
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost
Stock-based compensation
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
AOCI Attributable to Parent [Member]
Stockholders’ equity:
Short-term marketable securities
Leasehold Improvements [Member]
Property, Plant and Equipment, Policy [Policy Text Block]
us-gaap_OtherNonoperatingExpense
Other expenses
Other income (expense), net
Other income (expense), net
Long-Lived Tangible Asset [Axis]
us-gaap_NonoperatingIncomeExpense
Total other income (expense), net
Other income (expense), net
Long-Lived Tangible Asset [Domain]
Segment Reporting Disclosure [Text Block]
Net operating loss carryforwards
Research and development credit carryforwards
Foreign tax credit carryforwards
Current assets:
Fair Value Disclosures [Text Block]
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations
Cash, cash equivalents and restricted cash at beginning of period
Cash, cash equivalents and restricted cash at end of period
Contractual Obligation, Fiscal Year Maturity [Table Text Block]
Interest income
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
Net increase (decrease) in cash and cash equivalents
us-gaap_NetCashProvidedByUsedInFinancingActivities
Net cash used in financing activities
us-gaap_Liabilities
Total liabilities
Commitments and contingencies (Note 9)
Income from operations
Income from operations
us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Contract with Customer, Liability, Revenue Recognized
us-gaap_NetCashProvidedByUsedInOperatingActivities
Net cash provided by operating activities
Other income (expense), net:
us-gaap_NetCashProvidedByUsedInInvestingActivities
Net cash used in investing activities
Prepaid expenses and other current assets
Cost of revenues
Derivatives, Reporting of Derivative Activity [Policy Text Block]
us-gaap_GrossProfit
Gross profit
Accounting Standards Update 2014-09 [Member]
Accounting Standards Update [Domain]
Concentration Risk, Credit Risk, Policy [Policy Text Block]
us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation
Payments for taxes related to net share settlement of equity awards
us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment
Fixed assets
Accounting Standards Update [Axis]
us-gaap_PaymentsForRepurchaseOfCommonStock
Repurchase of common stock
Retained Earnings [Member]
Proceeds from exercise of stock options
Revenues
Revenue
Deferred Compensation, Share-based Payments [Member]
State
us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit
State
qlys_CapitalizedContractCosttAmortizationPeriod
Capitalized Contract Cost, Amortization Period (Year)
Represents the amortization period for capitalized contract costs.
Foreign
us-gaap_StockRepurchaseProgramPeriodInForce1
Stock Repurchase Program, Period in Force (Year)
us-gaap_DeferredForeignIncomeTaxExpenseBenefit
Foreign
Additional Paid-in Capital [Member]
Common Stock [Member]
Federal
Preferred Stock [Member]
us-gaap_StockRepurchaseProgramAuthorizedAmount1
Stock Repurchase Program, Authorized Amount
us-gaap_DeferredFederalIncomeTaxExpenseBenefit
Federal
qlys_ContractWithCustomerPeriod
Contract with Customer, Period (Year)
Represents the period to transfer good or service to customer.
Equity Components [Axis]
Equity Component [Domain]
qlys_SharebasedCompensationArrangementBySharebasedPaymentAwardTargetPercentage
Share-based Compensation Arrangement by Share-based Payment Award, Target Percentage
The target percentage for vesting of equity-based award under share based payment arrangement.
us-gaap_CurrentIncomeTaxExpenseBenefit
Total current provision
Remaining performance obligations, period (Year)
Remaining performance obligations
Non-Qualified Stock Options (NSOs) and Restricted Stock Units (RSUs) [Member]
Represents non-qualified stock options and restricted stock units.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]
us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign
Foreign
Foreign Exchange Contracts for GBP and Euro [Member]
Information related to foreign exchange contracts for BPG and Euro.
Foreign Exchange Contracts for INR [Member]
Information related to foreign exchange contracts for INR.
Performance Shares, Tranche Two [Member]
Information related to tranche two of performance shares.
Performance Shares, Tranche Three [Member]
Information related to tranche three of performance shares.
Domestic
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Axis]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]
Reclassification out of Accumulated Other Comprehensive Income [Domain]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]
State and Local Jurisdiction [Member]
Income Tax Authority [Axis]
Income Tax Authority [Domain]
Disaggregation of Revenue [Table Text Block]
Domestic Tax Authority [Member]
Foreign Tax Authority [Member]
us-gaap_RepaymentsOfLongTermCapitalLeaseObligations
Principal payments under finance lease obligations
Revenue from Contract with Customer [Text Block]
Document Annual Report
Accounts Receivable [Policy Text Block]
Computer Equipment [Member]
Entity Incorporation, State or Country Code
General and Administrative Expense [Member]
us-gaap_UnrecognizedTaxBenefits
Unrecognized tax benefits beginning balance
Total unrecognized tax benefits
us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate
Unrecognized Tax Benefits that Would Impact Effective Tax Rate
Accounting Policies [Abstract]
us-gaap_OpenTaxYear
Open Tax Year
Document Transition Report
Basis of Accounting, Policy [Policy Text Block]
us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations
Lapse of statute of limitations
Entity Interactive Data Current
Selling and Marketing Expense [Member]
Gross increase for tax positions of prior years
Security Exchange Name
us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions
Gross decrease for tax positions of prior years
Gross increase for tax positions of current year
Title of 12(b) Security
Cost of Sales [Member]
Research and Development Expense [Member]
Income Statement Location [Axis]
Income Statement Location [Domain]
us-gaap_TaxCreditCarryforwardAmount
Tax Credit Carryforward, Amount
Research Tax Credit Carryforward [Member]
Antidilutive securities (in shares)
us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding
Diluted (in shares)
Weighted-average shares used in computing net income per share - diluted (in shares)
us-gaap_PurchaseObligation
Total purchase commitment
Tax Credit Carryforward [Axis]
Tax Credit Carryforward, Name [Domain]
us-gaap_OperatingLossCarryforwards
Operating Loss Carryforwards, Total
2024
us-gaap_PurchaseObligationDueInFourthYear
2025
us-gaap_PurchaseObligationDueInFifthYear
2022
us-gaap_PurchaseObligationDueInSecondYear
Statement [Table]
2023
us-gaap_PurchaseObligationDueInThirdYear
Statement of Financial Position [Abstract]
Diluted (in dollars per share)
Weighted-average shares used in computing net income per share - basic (in shares)
Basic (in shares)
Excess tax benefits related to stock-based compensation
us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments
Other
2021
us-gaap_PurchaseObligationDueInNextTwelveMonths
us-gaap_EffectiveIncomeTaxRateContinuingOperations
Provision for (benefit from) income taxes
Business Acquisition [Axis]
Basic (in dollars per share)
Business Acquisition, Acquiree [Domain]
Change in valuation allowance
Statement of Cash Flows [Abstract]
Statement of Stockholders' Equity [Abstract]
Income Statement [Abstract]
Other comprehensive income (loss), net of tax
Other comprehensive income (loss), net of tax
us-gaap_BusinessCombinationContingentConsiderationLiability
Business Combination, Contingent Consideration, Liability, Total
Contract with Customer, Sales Channel [Axis]
Contract with Customer, Sales Channel [Domain]
Sales Channel, Directly to Consumer [Member]
Sales Channel, Through Intermediary [Member]
Quarterly Financial Information [Table Text Block]
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]
Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]
us-gaap_EffectiveIncomeTaxRateReconciliationDeductionsExtraterritorialIncomeExclusion
Foreign-derived intangible income deduction
Issuance of common stock upon vesting of restricted stock units
Represents amount of restricted stock award vested during period.
Investments Classified by Contractual Maturity Date [Table Text Block]
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
Lessee, Operating Lease, Supplemental Cash Flow Disclosure [Table Text Block]
Tabular disclosure of lessee's supplemental cash flow information associated with operating lease.
Lessee, Weighted Average Remaining Lease Term and Weighted Average Discount Rate [Table Text Block]
Tabular disclosure of lessee's weighted average remaining lease term and weighted average discount rate.
us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost
Stock-based compensation
Description Of Business Policy [Policy Text Block]
Disclosure of accounting policy for description of business.
Risk and Uncertainties, Policy [Policy Text Block]
Disclosure of accounting policy for risk and uncertainties.
Issuance of common stock upon vesting of restricted stock units (in shares)
Number of shares issued during period for restricted stock vested.
Foreign Government Agencies [Member]
Information related to foreign government agencies.
Finance leases, weighted average discount rates
qlys_DeferredTaxAssetsOperatingLeaseLiabilities
Operating lease liabilities
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from operating lease liabilities.
Foreign [Member]
Information related to foreign countries.
State taxes
Foreign source income
Fair Value, Assets Measured on Recurring Basis [Table Text Block]
us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch
Federal and state research and development credit
Finance leases, weighted average remaining lease term (Year)
Cash flows from financing activities:
Other Geographic Areas [Member]
Represents information related to other geographic areas.
Federal statutory rate
Other noncurrent liabilities
The 2000 Equity Incentive Plan [Member]
Represents plan 2000.
us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities
Payment for Contingent Consideration Liability, Investing Activities
The 2012 Equity Incentive Plan [Member]
Represents plan 2012.
Corporate Bond Securities [Member]
Expected to vest, number of shares (in shares)
Represents vested and expected to vest outstanding number
us-gaap_StockholdersEquity
Total stockholders’ equity
Accumulated other comprehensive income (loss)
Balances
Balances
Deferred revenues, noncurrent
Other comprehensive income (loss):
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities
Net Tangible Assets Acquired/ (liabilities assumed)
Class of Stock [Axis]
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities
Deferred Tax Liability
us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization
Property and equipment
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
us-gaap_PaymentsToAcquireBusinessesGross
Acquisition of businesses, net of cash acquired, and purchases of intangible assets
Assets and Liabilities, Lease [Table Text Block]
Tabular disclosure of lease assets and liabilities.
Weighted average exercise price per share, outstanding (in dollars per share)
us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax
Reclassification adjustment for net gain realized and included in net income, net of tax effect of $129, $35 and $0 in fiscal years 2020, 2019 and 2018, respectively
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Unrealized loss, securities
Weighted average remaining contractual life, outstanding 2 (Year)
qlys_LeaseRightOfUseAsset
Total lease assets
Represents right of use assets for lease.
Unrealized gains, securities
Number of shares, exercisable (in shares)
qlys_LeaseLiability
Total lease liabilities
Represents information related to lease liability.
Weighted average exercise price per share, exercisable (in dollars per share)
us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent
Total change in unrealized gain (loss) on cash flow hedges, net of tax
Adya [Member]
Represents information related to Adya.
Exercise price range, upper limit (in dollars per share)
qlys_MarketableSecuritiesInUnrealizedLossPositionsMoreThan12MonthsQualitativeDisclosureNumberOfPositions
Marketable Securities In Unrealized Loss Positions, More Than 12 Months Qualitative Disclosure, Number Of Positions
Represents number of positions for marketable securities in unrealized loss positions for more than 12 months qualitative disclosure.
Number of shares, outstanding (in shares)
Change in net unrealized gain (loss), net of tax effect of $486, ($136) and $0 in fiscal years 2020, 2019 and 2018, respectively
Exercise Price Range [Axis]
Exercise Price Range [Domain]
Exercise price range, lower limit (in dollars per share)