v3.26.3
Revenue and Related Matters - Schedule of Timing of Revenue Recognition Liabilities per Segment (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Disaggregation of Revenue [Line Items]        
Total revenues $ 1,504,791 $ 1,524,072 $ 4,691,775 $ 4,744,656
Transferred over time        
Disaggregation of Revenue [Line Items]        
Total revenues 1,384,577 1,362,968 4,150,513 4,090,501
Transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Total revenues 120,214 161,104 541,262 654,155
Insights        
Disaggregation of Revenue [Line Items]        
Total revenues 1,292,434 1,270,724 3,876,499 3,789,798
Insights | Transferred over time        
Disaggregation of Revenue [Line Items]        
Total revenues 1,290,381 1,268,460 3,870,284 3,781,197
Insights | Transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Total revenues 2,053 2,264 6,215 8,601
Conferences        
Disaggregation of Revenue [Line Items]        
Total revenues 86,003 74,554 408,485 358,558
Conferences | Transferred over time        
Disaggregation of Revenue [Line Items]        
Total revenues 0 0 0 0
Conferences | Transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Total revenues 86,003 74,554 408,485 358,558
Consulting        
Disaggregation of Revenue [Line Items]        
Total revenues 126,354 123,573 387,399 418,873
Consulting | Transferred over time        
Disaggregation of Revenue [Line Items]        
Total revenues 94,196 94,043 280,155 308,077
Consulting | Transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Total revenues $ 32,158 29,530 107,244 110,796
Other        
Disaggregation of Revenue [Line Items]        
Total revenues   55,221 19,392 177,427
Other | Transferred over time        
Disaggregation of Revenue [Line Items]        
Total revenues   465 74 1,227
Other | Transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Total revenues   $ 54,756 $ 19,318 $ 176,200