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Goodwill and Intangible Assets - Changes in Carrying Amounts of Goodwill (Details) - USD ($) $ in Thousands				12 Months Ended
	Sep. 17, 2021	Feb. 09, 2021	Aug. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Line Items]
Beginning balance				$ 1,525,000	$ 1,313,101
Goodwill acquired				97,032	202,901
Goodwill written off related to sale of a business				(50,277)	(4,751)
Purchase accounting adjustments				(932)	7,591
Foreign exchange translation				(6,739)	6,158
Goodwill impairment on business				(32,629)	0	$ 0
Ending balance				1,531,455	1,525,000	1,313,101
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| B2B Backup Business
Goodwill [Line Items]
Goodwill written off related to sale of a business	$ (49,000)
Goodwill impairment on business				(32,600)
Cybersecurity and Martech
Goodwill [Line Items]
Beginning balance				582,066
Ending balance				534,796	582,066
Digital Media
Goodwill [Line Items]
Beginning balance				942,934
Ending balance				996,659	942,934
Voice, Backup, Security and CPP Segment
Goodwill [Line Items]
Goodwill written off related to sale of a business		$ (1,300)
Reportable segments \| Cybersecurity and Martech
Goodwill [Line Items]
Beginning balance				582,066	557,940
Goodwill acquired				41,328	24,950
Goodwill written off related to sale of a business				(50,277)	(4,751)
Purchase accounting adjustments				505	(2,130)
Foreign exchange translation				(6,197)	6,057
Goodwill impairment on business				(32,629)
Ending balance				534,796	582,066	557,940
Reportable segments \| Digital Media
Goodwill [Line Items]
Beginning balance				942,934	755,161
Goodwill acquired				55,704	177,951
Goodwill written off related to sale of a business				0	0
Purchase accounting adjustments				(1,437)	9,721
Foreign exchange translation				(542)	101
Goodwill impairment on business				0
Ending balance				$ 996,659	$ 942,934	$ 755,161
Reportable segments \| Voice, Backup, Security and CPP Segment
Goodwill [Line Items]
Goodwill written off related to sale of a business			$ (4,800)