Stock-Based Compensation - Schedule of Unrecognized Stock-Based Compensation (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2025 USD ($)
Restricted stock units ("RSUs")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Stock-Based Compensation Expense (in thousands)	$ 325,334
Estimated Weighted Average Period (in years)	2 years 8 months 12 days
Performance stock units ("PSUs")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Stock-Based Compensation Expense (in thousands)	$ 6,121
Estimated Weighted Average Period (in years)	3 years 1 month 6 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Stock-Based Compensation Expense (in thousands)	$ 6,831
Estimated Weighted Average Period (in years)	2 years 3 months 18 days
2018 Employee Stock Purchase Plan ("2018 ESPP")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Stock-Based Compensation Expense (in thousands)	$ 16,262
Estimated Weighted Average Period (in years)	10 months 24 days

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Tenable Holdings, Inc. 10-Q