Annual report pursuant to Section 13 and 15(d)

SEGMENT INFORMATION - Segment Information (Details)

v3.22.0.1
SEGMENT INFORMATION - Segment Information (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Segment Reporting Disclosure [Line Items]      
Operating revenue $ 4,923.9 $ 4,127.5 $ 3,507.6
Operating income 1,138.0 676.6 (335.4)
Total assets 11,040.9 9,611.8  
Depreciation and amortization expense 480.4 391.0 331.1
Capital expenditures 490.5 430.7 375.9
General Corporate Expense      
Segment Reporting Disclosure [Line Items]      
Operating income (556.4) (618.3) (1,330.2)
Total assets 789.7 2,212.6  
Depreciation and amortization expense 74.3 65.5 70.9
Capital expenditures 200.3 161.8 155.0
Total Workforce Solutions      
Segment Reporting Disclosure [Line Items]      
Operating revenue 2,035.4 1,461.7 971.1
Total Workforce Solutions | Operating Segments      
Segment Reporting Disclosure [Line Items]      
Operating revenue 2,035.4 1,461.7 971.1
Operating income 1,000.7 703.9 391.3
Total assets 3,888.3 1,632.5  
Depreciation and amortization expense 106.5 71.9 55.8
Capital expenditures 73.5 74.6 50.5
U.S. Information Solutions | Operating Segments      
Segment Reporting Disclosure [Line Items]      
Operating revenue 1,786.7 1,711.2 1,531.2
Operating income 551.8 515.3 493.9
Total assets 3,091.4 2,330.5  
Depreciation and amortization expense 158.5 120.2 85.8
Capital expenditures 92.9 126.0 93.6
International      
Segment Reporting Disclosure [Line Items]      
Operating revenue 1,101.8 954.6 1,005.3
International | Operating Segments      
Segment Reporting Disclosure [Line Items]      
Operating revenue 1,101.8 954.6 1,005.3
Operating income 141.9 75.7 109.6
Total assets 3,271.5 3,436.2  
Depreciation and amortization expense 141.1 133.4 118.6
Capital expenditures $ 123.8 $ 68.3 $ 76.8