SEGMENT INFORMATION (Segment Information) (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Mar. 31, 2015 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Segment Reporting Disclosure [Line Items] | |||||||||||||
| Operating revenue | $ 801.1 | $ 804.1 | $ 811.3 | $ 728.3 | $ 666.3 | $ 667.4 | $ 678.1 | $ 651.8 | $ 3,144.9 | $ 2,663.6 | $ 2,436.4 | ||
| Operating income | 203.9 | $ 212.1 | $ 225.7 | $ 176.2 | 176.9 | $ 174.3 | $ 188.5 | $ 154.2 | 817.9 | 693.9 | 638.2 | ||
| Total assets | 6,664.0 | 4,501.5 | 6,664.0 | 4,501.5 | |||||||||
| Depreciation and amortization expense | 265.4 | 198.0 | 201.8 | ||||||||||
| Capital expenditures | [1] | 191.5 | 150.7 | 86.4 | |||||||||
| General Corporate Expense | |||||||||||||
| Segment Reporting Disclosure [Line Items] | |||||||||||||
| Operating income | (238.4) | (224.8) | (157.9) | ||||||||||
| Total assets | 376.8 | 321.0 | 376.8 | 321.0 | |||||||||
| Depreciation and amortization expense | 29.4 | 23.2 | 20.1 | ||||||||||
| Capital expenditures | 87.6 | 69.8 | 32.3 | ||||||||||
| U.S. Information Solutions | Operating Segments | |||||||||||||
| Segment Reporting Disclosure [Line Items] | |||||||||||||
| Operating revenue | 1,236.5 | 1,171.3 | 1,079.9 | ||||||||||
| Operating income | 537.0 | 491.2 | 421.0 | ||||||||||
| Total assets | 1,824.0 | 1,869.6 | 1,824.0 | 1,869.6 | |||||||||
| Depreciation and amortization expense | 82.1 | 83.3 | 86.7 | ||||||||||
| Capital expenditures | 19.1 | 21.9 | 16.6 | ||||||||||
| International | Operating Segments | |||||||||||||
| Segment Reporting Disclosure [Line Items] | |||||||||||||
| Operating revenue | 803.6 | 568.5 | 572.2 | ||||||||||
| Operating income | 111.4 | 113.5 | 121.0 | ||||||||||
| Total assets | 2,932.5 | 844.5 | 2,932.5 | 844.5 | |||||||||
| Depreciation and amortization expense | 101.6 | 40.1 | 44.2 | ||||||||||
| Capital expenditures | 50.3 | 25.7 | 15.2 | ||||||||||
| Workforce Solutions | Operating Segments | |||||||||||||
| Segment Reporting Disclosure [Line Items] | |||||||||||||
| Operating revenue | 702.2 | 577.7 | 490.1 | ||||||||||
| Operating income | 295.5 | 218.8 | 160.7 | ||||||||||
| Total assets | 1,337.0 | 1,268.5 | 1,337.0 | 1,268.5 | |||||||||
| Depreciation and amortization expense | 42.7 | 42.0 | 42.6 | ||||||||||
| Capital expenditures | 22.2 | 22.1 | 13.1 | ||||||||||
| Global Consumer Solutions | Operating Segments | |||||||||||||
| Segment Reporting Disclosure [Line Items] | |||||||||||||
| Operating revenue | 402.6 | 346.1 | 294.2 | ||||||||||
| Operating income | 112.4 | 95.2 | 93.4 | ||||||||||
| Total assets | $ 193.7 | $ 197.9 | 193.7 | 197.9 | |||||||||
| Depreciation and amortization expense | 9.6 | 9.4 | 8.2 | ||||||||||
| Capital expenditures | $ 12.3 | $ 11.2 | $ 9.2 | ||||||||||
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