v2.4.1.9

Commitments and Contingencies (Leases) (Details) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Leased Assets [Line Items] |  |  |  |
Rent expense | $ 6,200,000 us-gaap_LeaseAndRentalExpense | $ 5,400,000 us-gaap_LeaseAndRentalExpense | $ 4,300,000 us-gaap_LeaseAndRentalExpense |
Deferred rent credit, noncurrent | 500,000 us-gaap_DeferredRentCreditNoncurrent | 600,000 us-gaap_DeferredRentCreditNoncurrent |  |
Capital Lease Obligations | Minimum |  |  |  |
Leased Assets [Line Items] |  |  |  |
Debt interest rate |  | 1.80%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_CapitalLeaseObligationsMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
Capital Addition Purchase Commitments | Capital Lease Obligations |  |  |  |
Leased Assets [Line Items] |  |  |  |
Debt face amount |  |  |  | 3,100,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_CapitalLeaseObligationsMember / us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis = us-gaap_CapitalAdditionsMember
Maintenance and Support |  |  |  |
Leased Assets [Line Items] |  |  |  |
Recorded unconditional purchase obligation | $ 0 us-gaap_RecordedUnconditionalPurchaseObligation / us-gaap_RecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis = qlys_MaintenanceAndSupportMember | $ 300,000 us-gaap_RecordedUnconditionalPurchaseObligation / us-gaap_RecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis = qlys_MaintenanceAndSupportMember |  |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e39927-112707 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.26(c)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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- Definition Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25383-109308 + Details
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