Goodwill and Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 120,299	$ 119,816
Accumulated Amortization	(13,042)	(10,944)
Total intangible assets	$ 107,257	108,872
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	18 months
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	19 years
Customer, Affiliate and Advertiser Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 78,546	78,283
Accumulated Amortization	(7,803)	(6,595)
Total intangible assets	$ 70,743	$ 71,688
Customer, Affiliate and Advertiser Relationships [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	5 years	5 years
Customer, Affiliate and Advertiser Relationships [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	19 years	19 years
Developed Websites, Technology and Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	10 years	10 years
Gross Carrying Amount	$ 32,725	$ 32,535
Accumulated Amortization	(2,059)	(1,315)
Total intangible assets	30,666	31,220
Trademarks, Trade Name and Domain Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,652	7,619
Accumulated Amortization	(1,961)	(1,831)
Total intangible assets	$ 5,691	$ 5,788
Trademarks, Trade Name and Domain Name [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	5 years	5 years
Trademarks, Trade Name and Domain Name [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	16 years	16 years
Proprietary User Information Database and Internet Traffic [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	5 years	5 years
Gross Carrying Amount	$ 1,146	$ 1,149
Accumulated Amortization	(1,146)	(1,149)
Non-Compete Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	230	230
Accumulated Amortization	(73)	(54)
Total intangible assets	$ 157	$ 176
Non-Compete Agreement [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	1 year 6 months	1 year 6 months
Non-Compete Agreement [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	3 years	3 years