Acquisitions - Additional Information (Detail) - USD ($)				3 Months Ended		9 Months Ended
	Sep. 01, 2021	Jul. 01, 2021	Oct. 13, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Net revenue				$ 199,008,000	$ 62,978,000	$ 526,298,000	$ 172,343,000
Cisneros Interactive Noncontrolling Ownership
Business Acquisition [Line Items]
Noncontrolling interest			49.00%
Cisneros Interactive
Business Acquisition [Line Items]
Ownership interest acquired	100.00%		51.00%
Business acquisition date			Oct. 13, 2020
Aggregate cash consideration			$ 29,900,000
Business acquisition description of acquired entity			Subject to the terms of the Put and Call Agreement, if certain minimum EBITDA targets are met, the Sellers had the right (the “Put Option”), between March 15, 2024 and June 13, 2024, to cause the Company to purchase all (but not less than all) the remaining 49% of the issued and outstanding shares of Cisneros Interactive stock at a purchase price to be based on a pre-determined multiple of six times Cisneros Interactive’s 12-month EBITDA in the preceding calendar year. The Sellers also had the right to exercise the Put Option upon the occurrence of certain events, between March 2022 and April 2024.
Redeemable noncontrolling interest			$ 30,800,000
Accounts receivables assets acquired, fair value			50,500,000
Gross amount account receivables asset acquired			54,000,000.0
Amount due under contract expected to be uncollectible			$ 3,500,000
Gain Loss on Acquisition of Minority Interest	$ 0
Fair value of the contingent consideration recognized	$ 84,400,000
Contingent consideration current				26,500,000		26,500,000
Contingent consideration noncurrent liabilities				57,900,000		57,900,000
Net revenue				116,600,000		320,000,000.0
Net Income				$ 4,800,000		$ 13,400,000
Remaining ownership interest acquired	49.00%			49.00%		49.00%
Business combination consideration, transferred	$ 10,000,000
Acquisition fees and costs					$ 800,000		$ 800,000
Cisneros Interactive | Maximum
Business Acquisition [Line Items]
Period of discounted cost of debt rate	3 years
Business combination consideration, transferred	$ 10,000,000
Cisneros Interactive | Maximum | Discount Rate
Business Acquisition [Line Items]
Discounted cost of debt rate	0.072
Cisneros Interactive | Minimum | Discount Rate
Business Acquisition [Line Items]
Discounted cost of debt rate	0.065
Cisneros Interactive | Put Option
Business Acquisition [Line Items]
Agreed future ownership Interest acquired			49.00%
Cisneros Interactive | Call Option
Business Acquisition [Line Items]
Agreed future ownership Interest acquired			49.00%
Business acquisition description of acquired entity			Additionally, subject to the terms of the Put and Call Agreement, the Company had the right (the “Call Option”), in calendar year 2024, to purchase all (but not less than all) the remaining 49% of the issued and outstanding shares of Cisneros Interactive stock at a purchase price to be based on a pre-determined multiple of six times of Cisneros Interactive’s 12-month EBITDA in calendar year 2023.
MediaDonuts
Business Acquisition [Line Items]
Ownership interest acquired		100.00%
Business acquisition date		Jul. 01, 2021
Aggregate cash consideration		$ 15,100,000
Accounts receivables assets acquired, fair value		9,900,000
Gross amount account receivables asset acquired		10,200,000
Amount due under contract expected to be uncollectible		$ 300,000
Period of discounted cost of debt rate		3 years
Contingent consideration noncurrent liabilities				$ 20,300,000		$ 20,300,000
Net revenue				12,100,000		12,100,000
Net Income				0		0
Business combination consideration, transferred		$ 17,100,000
Decrease in purchase consideration				$ 1,200,000
Business combination, contingent earn-out payments		7,400,000
Acquisition fees and costs						$ 700,000
Fair value of contingent consideration recognized		$ 20,300,000
MediaDonuts | Maximum | Discount Rate
Business Acquisition [Line Items]
Discounted cost of debt rate		0.067
MediaDonuts | Minimum | Discount Rate
Business Acquisition [Line Items]
Discounted cost of debt rate		0.058