XML 49 R39.htm IDEA: XBRL DOCUMENT v3.21.2
Revenue and Related Matters - Disaggregation of Revenue by Geographic Area (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Disaggregation of Revenue [Line Items]        
Total revenues $ 1,167,319 $ 973,135 $ 2,271,357 $ 1,992,026
Research        
Disaggregation of Revenue [Line Items]        
Total revenues 1,003,238 875,329 1,982,970 1,784,620
Conferences        
Disaggregation of Revenue [Line Items]        
Total revenues 58,179 317 82,981 14,187
Consulting        
Disaggregation of Revenue [Line Items]        
Total revenues 105,902 97,489 205,406 193,219
United States and Canada        
Disaggregation of Revenue [Line Items]        
Total revenues 746,365 631,579 1,454,783 1,281,878
United States and Canada | Research        
Disaggregation of Revenue [Line Items]        
Total revenues 646,432 573,245 1,277,765 1,163,400
United States and Canada | Conferences        
Disaggregation of Revenue [Line Items]        
Total revenues 40,328 317 59,927 6,297
United States and Canada | Consulting        
Disaggregation of Revenue [Line Items]        
Total revenues 59,605 58,017 117,091 112,181
Europe, Middle East and Africa        
Disaggregation of Revenue [Line Items]        
Total revenues 286,683 226,968 549,959 465,137
Europe, Middle East and Africa | Research        
Disaggregation of Revenue [Line Items]        
Total revenues 236,756 196,854 466,957 402,794
Europe, Middle East and Africa | Conferences        
Disaggregation of Revenue [Line Items]        
Total revenues 14,468 0 17,181 2,147
Europe, Middle East and Africa | Consulting        
Disaggregation of Revenue [Line Items]        
Total revenues 35,459 30,114 65,821 60,196
Other International        
Disaggregation of Revenue [Line Items]        
Total revenues 134,271 114,588 266,615 245,011
Other International | Research        
Disaggregation of Revenue [Line Items]        
Total revenues 120,050 105,230 238,248 218,426
Other International | Conferences        
Disaggregation of Revenue [Line Items]        
Total revenues 3,383 0 5,873 5,743
Other International | Consulting        
Disaggregation of Revenue [Line Items]        
Total revenues $ 10,838 $ 9,358 $ 22,494 $ 20,842