Business Acquisitions - Supplementary Information on Unaudited Pro Forma Financial Basis (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fiscal 2022 Acquisitions
Revenues	$ 1,407,300	$ 1,461,178
Net income from continuing operations	$ 64,877	$ 398,201
EPS - Basic (in usd per share)	$ 1.38	$ 8.67
EPS - Diluted (in usd per share)	$ 1.38	$ 8.31
Fiscal 2021 Acquisitions
Revenues		$ 1,482,323	$ 1,267,280
Net income from continuing operations		$ 416,348	$ 33,351
EPS - Basic (in usd per share)		$ 9.06	$ 0.72
EPS - Diluted (in usd per share)		$ 8.69	$ 0.71
SEOmoz Acquisition
Revenues		$ 1,438,099	$ 1,207,910
Net income from continuing operations		$ 406,281	$ 29,382
EPS - Basic (in usd per share)		$ 8.84	$ 0.63
EPS - Diluted (in usd per share)		$ 8.48	$ 0.62
Fiscal 2020 Acquisitions
Revenues			$ 1,339,927
Net income from continuing operations			$ 21,450
EPS - Basic (in usd per share)			$ 0.46
EPS - Diluted (in usd per share)			$ 0.45
RetailMeNot, Inc.
Revenues			$ 1,308,731
Net income from continuing operations			$ 23,395
EPS - Basic (in usd per share)			$ 0.50
EPS - Diluted (in usd per share)			$ 0.49