The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Investments (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Investments (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jul. 12, 2021
Schedule of Equity Method Investments [Line Items]
Equity in earnings of investee	$ 1,141	$ 0	$ 1,141	$ 0
Vistar Media
Schedule of Equity Method Investments [Line Items]
Equity method investment					$ 30,000
Minority interest					20.00%