Depreciation and Amortization - Depreciation and Amortization Expense Excluded from Operating Expenses in its Condensed Consolidated Statements of Income and Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$ 68,627	$ 60,749
Direct advertising expenses
Property, Plant and Equipment [Line Items]
Depreciation and amortization	64,237	56,472
General and administrative expenses
Property, Plant and Equipment [Line Items]
Depreciation and amortization	1,176	1,107
Corporate expenses
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$ 3,214	$ 3,170