$QLYS
Qualys Inc Stock $qlys

$qlys Overview Financials Valuation SEC Filings Company Website

2019 Form 10-K Financial Statement

#000162828020001963 Filed on February 21, 2020

Income Statement

Concept	2019	2018 Q4	2018 Q3
Revenue	$321.6M	$74.20M	$71.66M
YoY Change	15.32%	17.94%	20.45%
Cost Of Revenue	$69.52M	$17.53M	$16.51M
YoY Change	5.03%	21.65%	29.72%
Gross Profit	$252.1M	$56.68M	$55.15M
YoY Change	18.52%	16.84%	17.93%
Gross Profit Margin	78.38%	76.39%	76.96%
Selling, General & Admin	$111.6M	$28.66M	$24.53M
YoY Change	2.3%	5.33%	-1.97%
% of Gross Profit	44.27%	50.56%	44.48%
Research & Development	$68.24M	$15.07M	$12.50M
YoY Change	28.14%	30.14%	14.77%
% of Gross Profit	27.07%	26.59%	22.67%
Depreciation & Amortization	$31.20M	$7.700M	$7.000M
YoY Change	7.95%	40.0%	32.08%
% of Gross Profit	12.38%	13.59%	12.69%
Operating Expenses	$179.8M	$43.73M	$37.03M
YoY Change	10.78%	12.76%	3.11%
Operating Profit	$72.25M	$12.94M	$18.12M
YoY Change	43.47%	33.04%	66.99%
Interest Expense	$106.0K	$1.830M	$35.00K
YoY Change	-38.37%	157.75%
% of Operating Profit	0.15%	14.14%	0.19%
Other Income/Expense, Net	$7.730M	$1.862M	$1.116M
YoY Change	51.36%	185.58%	66.32%
Pretax Income	$79.98M	$14.81M	$19.23M
YoY Change	59.93%	42.62%	66.95%
Income Tax	$10.65M	$410.0K	-$4.200M
% Of Pretax Income	13.31%	2.77%	-21.84%
Net Earnings	$69.34M	$14.40M	$23.47M
YoY Change	21.0%	404.03%	177.67%
Net Earnings / Revenue	21.56%	19.41%	32.75%
Basic Earnings Per Share	$1.77	$0.37	$0.60
Diluted Earnings Per Share	$1.68	$0.35	$0.56
COMMON SHARES
Basic Shares Outstanding	39.08M	39.38M shares	39.17M shares
Diluted Shares Outstanding	41.28M		42.20M shares

Balance Sheet

Concept	2019	2018 Q4	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$298.9M	$289.2M	$326.5M
YoY Change	3.35%	0.28%	7.86%
Cash & Equivalents	$87.60M	$41.03M	$97.96M
Short-Term Investments	$211.3M	$248.1M	$228.5M
Other Short-Term Assets	$18.70M	$14.00M	$16.60M
YoY Change	33.57%	-15.15%	-9.29%
Inventory
Prepaid Expenses
Receivables	$78.00M	$75.83M	$58.61M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$395.6M	$379.0M	$401.7M
YoY Change	4.38%	2.6%	9.35%
LONG-TERM ASSETS
Property, Plant & Equipment	$101.1M	$61.44M	$59.36M
YoY Change	64.66%	0.0%	15.75%
Goodwill		$7.225M	$7.300M
YoY Change		466329.95%	711.11%
Intangibles		$21.98M	$19.84M
YoY Change		0.0%	241.94%
Long-Term Investments	$119.5M	$79.20M	$66.60M
YoY Change	50.88%	17.86%	64.85%
Other Assets	$35.10M	$11.78M	$8.115M
YoY Change	-4.88%	440.63%	296.24%
Total Long-Term Assets	$280.0M	$206.7M	$184.3M
YoY Change	35.46%	22.92%	37.56%
TOTAL ASSETS
Total Short-Term Assets	$395.6M	$379.0M	$401.7M
Total Long-Term Assets	$280.0M	$206.7M	$184.3M
Total Assets	$675.6M	$585.7M	$586.0M
YoY Change	15.35%	8.96%	16.89%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$800.0K	$5.588M	$4.723M
YoY Change	-85.71%	388.46%	237.84%
Accrued Expenses	$30.30M	$26.70M	$23.21M
YoY Change	-19.41%	24.49%	58.1%
Deferred Revenue		$164.6M
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$100.0K	$1.600M
YoY Change	-93.75%
Total Short-Term Liabilities	$223.5M	$196.9M	$183.0M
YoY Change	13.51%	18.78%	23.48%
LONG-TERM LIABILITIES
Long-Term Debt	$100.0K	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$65.30M	$10.36M	$11.26M
YoY Change	112.01%	-6.41%	19.73%
Total Long-Term Liabilities	$65.40M	$10.36M	$11.26M
YoY Change	112.34%	-6.41%	19.73%
TOTAL LIABILITIES
Total Short-Term Liabilities	$223.5M	$196.9M	$183.0M
Total Long-Term Liabilities	$65.40M	$10.36M	$11.26M
Total Liabilities	$288.8M	$227.7M	$211.9M
YoY Change	26.83%	17.38%	21.98%
SHAREHOLDERS EQUITY
Retained Earnings		$27.96M	$45.81M
YoY Change		-29.96%	23.13%
Common Stock		$39.00K	$39.00K
YoY Change		0.0%	2.63%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$386.8M	$358.0M	$374.1M
YoY Change
Total Liabilities & Shareholders Equity	$675.6M	$585.7M	$586.0M
YoY Change	15.35%	8.96%	16.89%

Cashflow Statement

Concept	2019	2018 Q4	2018 Q3
OPERATING ACTIVITIES
Net Income	$69.34M	$14.40M	$23.47M
YoY Change	21.0%	404.03%	177.67%
Depreciation, Depletion And Amortization	$31.20M	$7.700M	$7.000M
YoY Change	7.95%	40.0%	32.08%
Cash From Operating Activities	$160.6M	$26.70M	$31.60M
YoY Change	28.01%	3.49%	-3.95%
INVESTING ACTIVITIES
Capital Expenditures	$27.57M	-$3.300M	-$6.300M
YoY Change	21.07%	-70.54%	-52.99%
Acquisitions
YoY Change
Other Investing Activities	-$7.500M	-$41.70M	$7.700M
YoY Change	-89.41%	75.21%	-111.81%
Cash From Investing Activities	-$35.03M	-$45.00M	$1.600M
YoY Change	-62.55%	28.57%	-102.04%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net	$86.42M
YoY Change	1.63%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-$79.05M	-38.60M	-22.00M
YoY Change	2.02%	-842.31%	-479.31%
NET CHANGE
Cash From Operating Activities	$160.6M	26.70M	31.60M
Cash From Investing Activities	-$35.03M	-45.00M	1.600M
Cash From Financing Activities	-$79.05M	-38.60M	-22.00M
Net Change In Cash	$46.53M	-56.90M	11.20M
YoY Change	-202.12%	1322.5%	-128.07%
FREE CASH FLOW
Cash From Operating Activities	$160.6M	$26.70M	$31.60M
Capital Expenditures	$27.57M	-$3.300M	-$6.300M
Free Cash Flow	$133.0M	$30.00M	$37.90M
YoY Change	29.55%	-18.92%	-18.14%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	1000000000	shares
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CY2019	dei	Amendment Flag AmendmentFlag	false
CY2019	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Document Period End Date DocumentPeriodEndDate	2019-12-31
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0001107843
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CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	683000	USD
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CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	39015034	shares
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CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Before Reclassification Adjustments Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesBeforeReclassificationAdjustmentsTax	-243000	USD
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CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	-136000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	0	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	35000	USD
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CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
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CY2019	dei	Entity File Number EntityFileNumber	001-35662
CY2019	dei	Entity Registrant Name EntityRegistrantName	QUALYS, INC.
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	77-0534145
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	919 E. Hillsdale Boulevard, 4th Floor
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Foster City
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	CA
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	94404
CY2019	dei	City Area Code CityAreaCode	650
CY2019	dei	Local Phone Number LocalPhoneNumber	801-6100
CY2019	dei	Security12b Title Security12bTitle	Common stock, $0.001 par value per share
CY2019	dei	Trading Symbol TradingSymbol	QLYS
CY2019	dei	Security Exchange Name SecurityExchangeName	NASDAQ
CY2019	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2019	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.47
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.08
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.68
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.37
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.01
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	39075000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	38876000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	37443000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	41345000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	41897000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	40071000	shares
CY2019	us-gaap	Net Income Loss NetIncomeLoss	69336000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	57304000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	40440000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax	1367000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax	-261000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-462000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	0	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-289000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-44000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	1367000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	28000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-418000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	515000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-40000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	134000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	381000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-40000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1748000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-418000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	71084000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	57292000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	40022000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	69336000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	57304000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	40440000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	31201000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	28904000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	20636000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	247000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	86000	USD
CY2017	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	657000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-202000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-9000	USD
CY2017	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-161000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	34892000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	30090000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	26961000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	1597000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	1136000	USD
CY2017	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1324000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	7095000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-2521000	USD
CY2017	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-2718000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	2456000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	11467000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	17966000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	6012000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	4970000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	53000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-1076000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	3515000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-454000	USD
CY2019	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	715000	USD
CY2018	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	1426000	USD
CY2017	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	1485000	USD
CY2019	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	28060000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	24725000	USD
CY2017	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	29830000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	0	USD
CY2018	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-501000	USD
CY2017	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	7343000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	160607000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	125464000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	107646000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	331131000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	339862000	USD
CY2017	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	299891000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	328350000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	285224000	USD
CY2017	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	231996000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	27573000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	22775000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	37818000	USD
CY2019	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	4050000	USD
CY2018	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	13633000	USD
CY2017	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	12482000	USD
CY2019	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	625000	USD
CY2017	qlys	Capitalized Software Development Costs CapitalizedSoftwareDevelopmentCosts	0	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-35029000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-93546000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-118195000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	86424000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	85040000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	24831000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	24053000	USD
CY2017	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	31327000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	15743000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	14879000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	20924000	USD
CY2019	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	1709000	USD
CY2018	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	1617000	USD
CY2017	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	0	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-79045000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-77483000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	10403000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	46533000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-45565000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-146000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	42226000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	87791000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	87937000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	88759000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	42226000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	87791000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	107000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	168000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	3000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	3031000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	2693000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1584000	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Net Nonmonetary Assets Acquired Liabilities Assumed1 NoncashOrPartNoncashAcquisitionNetNonmonetaryAssetsAcquiredLiabilitiesAssumed1	1650000	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Net Nonmonetary Assets Acquired Liabilities Assumed1 NoncashOrPartNoncashAcquisitionNetNonmonetaryAssetsAcquiredLiabilitiesAssumed1	4676000	USD
CY2017	us-gaap	Noncash Or Part Noncash Acquisition Net Nonmonetary Assets Acquired Liabilities Assumed1 NoncashOrPartNoncashAcquisitionNetNonmonetaryAssetsAcquiredLiabilitiesAssumed1	1000000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	235000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	4190000	USD
CY2017	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	2765000	USD
CY2016Q4	us-gaap	Stockholders Equity StockholdersEquity	258413000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	40440000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-418000	USD
CY2017	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	31327000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	-20924000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	26961000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	343544000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	57304000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	57304000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	24053000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	-14879000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	30308000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	357989000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	69336000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1748000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	24831000	USD
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	86424000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	-15743000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	35066000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	386803000	USD
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:120%;text-align:justify;text-indent:18px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#231f20;font-style:italic;font-weight:bold;">Use of Estimates</span></div><div style="line-height:120%;padding-top:8px;text-align:justify;text-indent:30px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of assets and liabilities at the date of the consolidated financial statements and the reported results of operations during the reporting period. The Company’s management regularly assesses these estimates, which primarily affect revenue recognition, the valuation of accounts receivable, goodwill and intangible assets, capitalization of internally developed software, stock-based compensation and the provision for income taxes. Actual results could differ from those estimates and such differences may be material to the accompanying consolidated financial statements.</span></div>
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="line-height:120%;text-align:justify;text-indent:30px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><br/></span></div><div style="line-height:120%;text-align:justify;text-indent:18px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#231f20;font-style:italic;font-weight:bold;">Concentration of Credit Risk</span></div><div style="line-height:120%;padding-top:8px;text-align:justify;text-indent:30px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#231f20;">The Company invests its cash and cash equivalents with major financial institutions. Cash balances with any one institution at times may be in excess of federally insured limits. Cash equivalents are invested in high-quality investment grade financial instruments and are diversified. The Company has not experienced any losses in such accounts and believes it is not exposed to any significant credit risk. </span></div><div style="line-height:120%;padding-top:8px;text-align:justify;text-indent:30px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#231f20;">Credit risk with respect to accounts receivable is dispersed due to the large number of customers. Collateral is not required for accounts receivable. </span><span style="font-family:Arial;font-size:10pt;color:#231f20;">As of December 31, 2019 and 2018</span><span style="font-family:Arial;font-size:10pt;color:#231f20;">,</span><span style="font-family:inherit;font-size:10pt;"> </span><span style="font-family:Arial;font-size:10pt;"><span>no</span></span><span style="font-family:inherit;font-size:10pt;"> </span><span style="font-family:Arial;font-size:10pt;color:#231f20;">customer or channel partner accounted for more than</span><span style="font-family:inherit;font-size:10pt;"> </span><span style="font-family:Arial;font-size:10pt;">10%</span><span style="font-family:inherit;font-size:10pt;"> </span><span style="font-family:Arial;font-size:10pt;color:#231f20;">of the Company's revenues and accounts receivable balance.</span><span style="font-family:inherit;font-size:10pt;"> </span></div>
CY2019Q4	us-gaap	Capitalized Computer Software Gross CapitalizedComputerSoftwareGross	1000000.0	USD
CY2019	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1
CY2019	us-gaap	Finite Lived Intangible Asset Useful Life FiniteLivedIntangibleAssetUsefulLife	P3Y
CY2018Q4	us-gaap	Capitalized Computer Software Gross CapitalizedComputerSoftwareGross	1300000	USD
CY2017Q4	us-gaap	Capitalized Computer Software Gross CapitalizedComputerSoftwareGross	400000	USD
CY2019Q4	qlys	Capitalized Computer Software Unamortized CapitalizedComputerSoftwareUnamortized	2000000.0	USD
CY2018Q4	qlys	Capitalized Computer Software Unamortized CapitalizedComputerSoftwareUnamortized	1200000	USD
CY2019	us-gaap	Derivatives Reporting Of Derivative Activity DerivativesReportingOfDerivativeActivity	<div style="line-height:120%;text-align:justify;text-indent:18px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-style:italic;font-weight:bold;">Derivative Financial Instruments</span></div><div style="line-height:120%;text-align:justify;text-indent:30px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><br/></span></div><div style="line-height:120%;text-align:justify;text-indent:30px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Derivative financial instruments are utilized by the Company to reduce foreign currency exchange risks. The Company uses foreign currency forward contracts to mitigate the impact of foreign currency fluctuations of certain non-U.S. dollar denominated asset positions, to date primarily cash and accounts receivable (non-designated forward contracts), as well as to manage foreign currency fluctuation risk related to forecasted transactions (designated cash flow hedges). Open contracts are recorded within prepaid expenses and other current assets, other noncurrent assets, accrued liabilities, or other noncurrent liabilities in the consolidated balance sheets. Gains and losses resulting from currency exchange rate movements on non-designated forward contracts are recognized in other income (expense), net. Any gains or losses from derivatives designated as cash flow hedges are first accumulated in AOCI and then reclassified to revenue when the hedged item impacts the consolidated statements of operations.</span></div>
CY2019	us-gaap	Advertising Expense AdvertisingExpense	74000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	87000	USD
CY2017	us-gaap	Advertising Expense AdvertisingExpense	482000	USD
CY2019	qlys	Foreign Currency Transaction Gain Loss Including Derivatives Before Tax ForeignCurrencyTransactionGainLossIncludingDerivativesBeforeTax	-400000	USD
CY2018	qlys	Foreign Currency Transaction Gain Loss Including Derivatives Before Tax ForeignCurrencyTransactionGainLossIncludingDerivativesBeforeTax	-600000	USD
CY2017	qlys	Foreign Currency Transaction Gain Loss Including Derivatives Before Tax ForeignCurrencyTransactionGainLossIncludingDerivativesBeforeTax	-400000	USD
CY2019Q4	qlys	Fair Value Asset Value Amortized Cost FairValueAssetValueAmortizedCost	417332000	USD
CY2019Q4	qlys	Fair Value Asset Value Unrealized Gains FairValueAssetValueUnrealizedGains	1071000	USD
CY2019Q4	qlys	Fair Value Asset Value Unrealized Losses FairValueAssetValueUnrealizedLosses	5000	USD
CY2019Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	418398000	USD
CY2018Q4	qlys	Fair Value Asset Value Amortized Cost FairValueAssetValueAmortizedCost	366421000	USD
CY2018Q4	qlys	Fair Value Asset Value Unrealized Gains FairValueAssetValueUnrealizedGains	22000	USD
CY2018Q4	qlys	Fair Value Asset Value Unrealized Losses FairValueAssetValueUnrealizedLosses	567000	USD
CY2018Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	365876000	USD
CY2019Q4	qlys	Available For Sale Securities Debt And Equity Maturities Next Twelve Months Fair Value AvailableForSaleSecuritiesDebtAndEquityMaturitiesNextTwelveMonthsFairValue	214731000	USD
CY2019Q4	qlys	Available For Sale Securities Debt And Equity Maturities Year One Through Two Fair Value AvailableForSaleSecuritiesDebtAndEquityMaturitiesYearOneThroughTwoFairValue	85617000	USD
CY2019Q4	qlys	Available For Sale Securities Debt And Equity Maturities After Year Two Fair Value AvailableForSaleSecuritiesDebtAndEquityMaturitiesAfterYearTwoFairValue	33890000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	334238000	USD
CY2019	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	700000	USD
CY2019	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	200000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	60579000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	942000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	32000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	1074000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	116000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-792000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-1120000	USD
CY2017	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	1310000	USD
CY2019	qlys	Foreign Currency Transaction Gain Loss Including Derivatives Before Tax ForeignCurrencyTransactionGainLossIncludingDerivativesBeforeTax	-354000	USD
CY2018	qlys	Foreign Currency Transaction Gain Loss Including Derivatives Before Tax ForeignCurrencyTransactionGainLossIncludingDerivativesBeforeTax	-577000	USD
CY2017	qlys	Foreign Currency Transaction Gain Loss Including Derivatives Before Tax ForeignCurrencyTransactionGainLossIncludingDerivativesBeforeTax	-355000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	183893000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	160672000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	123314000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	99230000	USD
CY2018Q4	qlys	Commission Asset Noncurrent CommissionAssetNoncurrent	4692000	USD
CY2019	us-gaap	Amortization Of Deferred Sales Commissions AmortizationOfDeferredSalesCommissions	2000000.0	USD
CY2018	us-gaap	Amortization Of Deferred Sales Commissions AmortizationOfDeferredSalesCommissions	1200000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	61442000	USD
CY2019	us-gaap	Depreciation Depreciation	24900000	USD
CY2018	us-gaap	Depreciation Depreciation	25100000	USD
CY2017	us-gaap	Depreciation Depreciation	19900000	USD
CY2019Q4	qlys	Commission Asset Current CommissionAssetCurrent	2568000	USD
CY2018Q4	qlys	Commission Asset Current CommissionAssetCurrent	1480000	USD
CY2019Q4	qlys	Commission Asset Noncurrent CommissionAssetNoncurrent	6454000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	67055000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	35437000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	13027000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	1454000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	343000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	138000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	117454000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	230828000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	27743000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	10988000	USD
CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	21976000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6100000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3700000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	700000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	16755000	USD
CY2019Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	40000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	16795000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	26844000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	4907000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	21936000	USD
CY2018Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	40000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	6081000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	6081000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	4427000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	100000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	66000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	0	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	16755000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	7400000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	7200000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	1549	USD
CY2018	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	5676	USD
CY2018Q4	us-gaap	Goodwill Goodwill	7225000	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	100	USD
CY2019	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	122	USD
CY2019Q4	us-gaap	Goodwill Goodwill	7447000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	40551000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	1299000	USD
CY2019Q4	qlys	Lease Rightof Use Asset LeaseRightofUseAsset	41850000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	7663000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	44015000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	54000	USD
CY2019Q4	qlys	Lease Liability LeaseLiability	51856000	USD
CY2018Q1	us-gaap	Finance Lease Liability FinanceLeaseLiability	3500000	USD
CY2018Q1	qlys	Capital Leased Assets Interest Rate CapitalLeasedAssetsInterestRate	0.05
CY2019Q4	qlys	Lease Office Building Square Feet LeaseOfficeBuildingSquareFeet	282000000	sqft
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	10603000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	130000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	9859000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	54000	USD
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	124000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	44015000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	54000	USD
CY2019	qlys	Lease Expense LeaseExpense	13900000	USD
CY2018	qlys	Lease Expense LeaseExpense	9900000	USD
CY2017	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	9600000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	8539000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	0	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	8652000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	0	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	8866000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	0	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	15583000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	0	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	62102000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	184000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	10424000	USD
CY2019Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	6000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	51678000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	178000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	7663000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y6M
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P1Y3M
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.050
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.050
CY2019Q4	us-gaap	Purchase Obligation PurchaseObligation	25300000	USD
CY2019Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	9325223	shares
CY2019Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	34892000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	30090000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	26961000	USD
CY2016	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y
CY2016Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	7527680	shares
CY2016Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	19.25
CY2016Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	101717000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	408225	shares
CY2017	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	40.82
CY2017	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	2997095	shares
CY2017	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	11.05
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	442919	shares
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	33.29
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	4495891	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	25.29
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y7M6D
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	153129000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	366786	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	79.79
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	1183235	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	20.33
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	250133	shares
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	39.61
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3429309	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	31.79
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y4M24D
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	149935000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	496145	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	87.10
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	901290	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	27.55
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	157489	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	71.04
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2866675	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	40.54
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	125647000	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber	2655987	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice	37.27
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1	P5Y10M24D
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue	124592000	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber	2099200	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice	28.39
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1	P5Y4M24D
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue	115916000	USD
CY2019Q4	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Number Of Outstanding Options ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions	2866675	shares
CY2019Q4	us-gaap	Sharebased Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Outstanding Options Weighted Average Exercise Price Beginning Balance1 SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1	40.54
CY2019	us-gaap	Sharebased Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Outstanding Options Weighted Average Remaining Contractual Term2 SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageRemainingContractualTerm2	P6Y
CY2019Q4	qlys	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Number Of Vested Options ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfVestedOptions	2099200000	shares
CY2019Q4	qlys	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Vested Options Weighted Average Exercise Price ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeVestedOptionsWeightedAverageExercisePrice	28.39
CY2018Q1	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	100000000.0	USD
CY2018Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	100000000.0	USD
CY2019Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	100000000.0	USD
CY2019	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1026455	shares
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	86400000	USD
CY2019Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	128500000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	72124000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	50010000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	34914000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	5458000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	4464000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	79983000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	7859000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	55468000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	39378000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-90000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-90000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	22000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	646000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	62000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	23000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	3000000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	1988000	USD
CY2017	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	1471000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	3556000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1960000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1516000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	7085000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-3449000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-1650000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	447000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	21000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-996000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-441000	USD
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CY2019	us-gaap	Revenues Revenues	321607000	USD
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CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	37443000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2401000	shares
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CY2019	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	463000	shares
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CY2019Q4	us-gaap	Revenues Revenues	84664000	USD
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CY2018Q3	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	1116000	USD
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CY2018Q1	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	1245000	USD
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CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	13266000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	14400000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	23469000	USD
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CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.53
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CY2018Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	683000	USD
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CY2017Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	816000	USD

Files In Submission

Name	View Source	Status
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$QLYS
Qualys Inc Stock $qlys

2019 Form 10-K Financial Statement

#000162828020001963 Filed on February 21, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$QLYS Qualys Inc Stock $qlys

2019 Form 10-K Financial Statement

#000162828020001963 Filed on February 21, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$QLYS
Qualys Inc Stock $qlys