v3.25.0.1

The Company and Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2024 USD ($) reportingUnit	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2018 USD ($)
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 1,200,000	$ 2,700,000
Accounts receivable	164,600,000	146,200,000	$ 121,800,000
Investments				$ 2,500,000
Dividends from investment	0	0	0
Impairment of long-lived assets	$ 0	0	0
Number of reporting units \| reportingUnit	1
Capitalized commission cost	5 years
Advertising expense	$ 2,900,000	3,000,000.0	$ 3,300,000
Software Developed for Internal Use
Restricted Cash and Cash Equivalents Items [Line Items]
Estimated useful life	3 years
Scanner appliances and other computer equipment
Restricted Cash and Cash Equivalents Items [Line Items]
Estimated useful lives	3 years
Minimum
Restricted Cash and Cash Equivalents Items [Line Items]
Estimated useful lives	3 years
Maximum
Restricted Cash and Cash Equivalents Items [Line Items]
Estimated useful lives	5 years
Derivative financial instrument term	13 months
Security Deposits \| Letter of Credit
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 1,200,000	1,200,000
Cash Held in Escrow With Blue Hexagon Acquisition
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 1,500,000	$ 1,500,000

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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QUALYS, INC. 10-K