Basis of presentation, merger agreement and accounting policies - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Total revenues	$ 803,111	$ 756,487	$ 2,362,115	$ 2,216,446
Subscription
Disaggregation of Revenue [Line Items]
Total revenues	377,368	368,672	1,158,101	1,130,490
Advertising & Marketing Services
Disaggregation of Revenue [Line Items]
Total revenues	320,764	364,234	1,010,490	1,027,957
Political
Disaggregation of Revenue [Line Items]
Total revenues	92,904	15,010	161,727	34,019
Other
Disaggregation of Revenue [Line Items]
Total revenues	$ 12,075	$ 8,571	$ 31,797	$ 23,980