v2.4.1.9

Stockholders' Equity (Details) (USD $) | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Oct. 03, 2012
--- | --- | --- | --- | --- | ---
Common Stock |  |  |  |  |
Options outstanding under equity incentive plans | 7,605,407 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber | 7,039,093 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber | 6,513,508 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber | 6,312,041 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber |
Total shares reserved for future issuance | 8,409,037 us-gaap_CommonStockCapitalSharesReservedForFutureIssuance |  |  |  |
Convertible Preferred Stock and Preferred Stock |  |  |  |  |
Preferred stock, shares authorized | 20,000,000 us-gaap_PreferredStockSharesAuthorized | 20,000,000 us-gaap_PreferredStockSharesAuthorized |  |  |
Preferred stock, par value per share (in dollars per share) | $ 0.001 us-gaap_PreferredStockParOrStatedValuePerShare | $ 0.001 us-gaap_PreferredStockParOrStatedValuePerShare |  |  |
2000 Equity Incentive Plan |  |  |  |  |
Common Stock |  |  |  |  |
Options outstanding under equity incentive plans | 3,970,662 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber / us-gaap_PlanNameAxis = qlys_A2000EquityIncentivePlanMember |  |  |  |
2012 Equity Incentive Plan |  |  |  |  |
Common Stock |  |  |  |  |
Options outstanding under equity incentive plans | 3,634,745 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber / us-gaap_PlanNameAxis = qlys_A2012EquityIncentivePlanMember |  |  |  |
Shares available for future grants under an equity incentive plan | 803,630 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant / us-gaap_PlanNameAxis = qlys_A2012EquityIncentivePlanMember |  |  |  |
Preferred Stock |  |  |  |  |
Convertible Preferred Stock and Preferred Stock |  |  |  |  |
Preferred stock, shares authorized |  |  |  |  | 20,000,000 us-gaap_PreferredStockSharesAuthorized / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember
Preferred stock, par value per share (in dollars per share) |  |  |  |  | $ 0.001 us-gaap_PreferredStockParOrStatedValuePerShare / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember

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