Quarterly report pursuant to Section 13 or 15(d)

Revenue Recognition - Disaggregation of Revenue (Details)

v3.20.4
Revenue Recognition - Disaggregation of Revenue (Details) - USD ($)
$ in Thousands
 3 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Disaggregation of Revenue [Line Items]    
Revenue $ 945,554 $ 818,229
United States    
Disaggregation of Revenue [Line Items]    
Revenue 790,179 678,852
United Kingdom    
Disaggregation of Revenue [Line Items]    
Revenue 64,786 73,002
Australia    
Disaggregation of Revenue [Line Items]    
Revenue 55,932 37,435
Rest of world    
Disaggregation of Revenue [Line Items]    
Revenue 34,657 28,940
Total U.S. state government agencies    
Disaggregation of Revenue [Line Items]    
Revenue 388,114 307,109
New York State government agencies    
Disaggregation of Revenue [Line Items]    
Revenue 75,356 97,223
Other U.S. state government agencies    
Disaggregation of Revenue [Line Items]    
Revenue 312,758 209,886
United States Federal Government agencies    
Disaggregation of Revenue [Line Items]    
Revenue 385,573 351,833
International government agencies    
Disaggregation of Revenue [Line Items]    
Revenue 147,342 130,816
Other, including local municipalities and commercial customers    
Disaggregation of Revenue [Line Items]    
Revenue 24,525 28,471
Performance-based    
Disaggregation of Revenue [Line Items]    
Revenue 293,960 292,758
Cost-plus    
Disaggregation of Revenue [Line Items]    
Revenue 384,483 362,811
Fixed price    
Disaggregation of Revenue [Line Items]    
Revenue 120,777 119,216
Time and materials    
Disaggregation of Revenue [Line Items]    
Revenue 146,334 43,444
U.S. Services    
Disaggregation of Revenue [Line Items]    
Revenue 384,934 312,281
U.S. Federal Services    
Disaggregation of Revenue [Line Items]    
Revenue 405,245 366,571
Outside the U.S.    
Disaggregation of Revenue [Line Items]    
Revenue 155,375 139,377
Program administration | U.S. Services    
Disaggregation of Revenue [Line Items]    
Revenue 293,844 236,907
Program administration | U.S. Federal Services    
Disaggregation of Revenue [Line Items]    
Revenue 327,790 281,688
Program administration | Outside the U.S.    
Disaggregation of Revenue [Line Items]    
Revenue 23,056 17,094
Technology solutions | U.S. Federal Services    
Disaggregation of Revenue [Line Items]    
Revenue 34,664 43,606
Assessments and appeals | U.S. Services    
Disaggregation of Revenue [Line Items]    
Revenue 32,615 33,831
Assessments and appeals | U.S. Federal Services    
Disaggregation of Revenue [Line Items]    
Revenue 42,791 41,277
Assessments and appeals | Outside the U.S.    
Disaggregation of Revenue [Line Items]    
Revenue 53,123 62,643
Workforce and children services | U.S. Services    
Disaggregation of Revenue [Line Items]    
Revenue 47,821 29,386
Workforce and children services | Outside the U.S.    
Disaggregation of Revenue [Line Items]    
Revenue 77,462 57,239
Other | U.S. Services    
Disaggregation of Revenue [Line Items]    
Revenue 10,654 12,157
Other | Outside the U.S.    
Disaggregation of Revenue [Line Items]    
Revenue $ 1,734 $ 2,401