Leases - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) ft²	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Lessee Lease Description [Line Items]
Remaining term description of leases	The Company’s existing leases have remaining terms of less than one year up to 30 years.
Non-cancelable operating lease expiration term	2024-12
Weighted average remaining lease term	9 years 10 months 24 days	11 years 4 months 24 days
Weighted average discount rate	6.30%	6.20%
Lease cost	$ 11,411	$ 12,878
Total rent expense under operating leases			$ 12,000
Direct Operating Expenses
Lessee Lease Description [Line Items]
Lease cost	5,900	6,100
Selling, General and Administrative Expenses
Lessee Lease Description [Line Items]
Lease cost	4,700	6,000
Corporate Expenses
Lessee Lease Description [Line Items]
Lease cost	$ 800	$ 800
Santa Monica
Lessee Lease Description [Line Items]
Area under operating leases for corporate headquarters | ft²	16,000
Lease Expiration Year	2021
Los Angeles
Lessee Lease Description [Line Items]
Area under operating leases for corporate headquarters | ft²	41,000
Lease Expiration Year	2026
Facilities and Broadcast Equipment
Lessee Lease Description [Line Items]
Non-cancelable operating lease expiration term	2050-11
Maximum
Lessee Lease Description [Line Items]
Remaining term of leases	30 years