Revenues - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 1,390,997	$ 1,416,722	$ 1,158,829
Contract liability, revenue recognized	174,700	153,000
Revenue, remaining performance obligation, amount	$ 21,200
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	93.00%
Performance obligation, expected duration	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	7.00%
Performance obligation, expected duration	12 months
Fiscal 2022 Acquisitions
Disaggregation of Revenue [Line Items]
Deferred revenue acquired	$ 21,474
Fiscal 2021 Acquisitions
Disaggregation of Revenue [Line Items]
Deferred revenue acquired		9,491
Point in time
Disaggregation of Revenue [Line Items]
Revenues	46,770	42,276	27,685
Over time
Disaggregation of Revenue [Line Items]
Revenues	1,344,227	1,374,446	1,131,144
Reportable segments
Disaggregation of Revenue [Line Items]
Revenues	1,390,997	1,416,722	1,158,828
Reportable segments | Digital Media
Disaggregation of Revenue [Line Items]
Revenues	1,079,172	1,069,300	811,360
Reportable segments | Digital Media | Advertising
Disaggregation of Revenue [Line Items]
Revenues	788,135	838,075	627,198
Reportable segments | Digital Media | Subscription
Disaggregation of Revenue [Line Items]
Revenues	244,694	197,354	166,219
Reportable segments | Digital Media | Other
Disaggregation of Revenue [Line Items]
Revenues	46,343	33,871	17,943
Reportable segments | Cybersecurity and Martech
Disaggregation of Revenue [Line Items]
Revenues	312,626	348,611	347,697
Reportable segments | Cybersecurity and Martech | Subscription
Disaggregation of Revenue [Line Items]
Revenues	312,626	348,611	347,697
Corporate, Non-Segment
Disaggregation of Revenue [Line Items]
Revenues	0	0	1
Intersegment Eliminations
Disaggregation of Revenue [Line Items]
Revenues	$ (801)	$ (1,189)	$ (229)