Annual report pursuant to Section 13 and 15(d)

SEGMENT INFORMATION (Segment Information) (Details)

v3.8.0.1
SEGMENT INFORMATION (Segment Information) (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Segment Reporting Disclosure [Line Items]                      
Operating revenue $ 838.5 $ 834.8 $ 856.7 $ 832.2 $ 801.1 $ 804.1 $ 811.3 $ 728.3 $ 3,362.2 $ 3,144.9 $ 2,663.6
Operating income 190.9 $ 152.9 $ 264.1 $ 216.8 203.9 $ 212.1 $ 225.7 $ 176.2 824.6 817.9 693.9
Total assets 7,233.4       6,664.0       7,233.4 6,664.0  
Depreciation and amortization expense                 287.8 265.4 198.0
Capital expenditures                 214.0 191.5 150.7
General Corporate Expense                      
Segment Reporting Disclosure [Line Items]                      
Operating income                 (322.0) (238.4) (224.8)
Total assets 1,019.0       376.8       1,019.0 376.8  
Depreciation and amortization expense                 38.9 29.4 23.2
Capital expenditures                 91.8 87.6 69.8
U.S. Information Solutions | Operating Segments                      
Segment Reporting Disclosure [Line Items]                      
Operating revenue                 1,262.7 1,236.5 1,171.3
Operating income                 539.1 537.0 491.2
Total assets 1,587.3       1,824.0       1,587.3 1,824.0  
Depreciation and amortization expense                 83.7 82.1 83.3
Capital expenditures                 18.6 19.1 21.9
International | Operating Segments                      
Segment Reporting Disclosure [Line Items]                      
Operating revenue                 932.3 803.6 568.5
Operating income                 169.4 111.4 113.5
Total assets 3,145.7       2,932.5       3,145.7 2,932.5  
Depreciation and amortization expense                 109.9 101.6 40.1
Capital expenditures                 59.7 50.3 25.7
Workforce Solutions | Operating Segments                      
Segment Reporting Disclosure [Line Items]                      
Operating revenue                 764.2 702.2 577.7
Operating income                 331.9 295.5 218.8
Total assets 1,227.4       1,337.0       1,227.4 1,337.0  
Depreciation and amortization expense                 42.1 42.7 42.0
Capital expenditures                 28.9 22.2 22.1
Global Consumer Solutions | Operating Segments                      
Segment Reporting Disclosure [Line Items]                      
Operating revenue                 403.0 402.6 346.1
Operating income                 106.2 112.4 95.2
Total assets $ 254.0       $ 193.7       254.0 193.7  
Depreciation and amortization expense                 13.2 9.6 9.4
Capital expenditures                 $ 15.0 $ 12.3 $ 11.2