SEGMENT INFORMATION (Operating Revenue and Operating Income by Operating Segment) (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Operating revenue	$ 804.1	$ 667.4	$ 2,343.8	$ 1,997.3
Operating income	212.1	174.3	614.0	517.0
Total assets	6,806.6		$ 6,806.6		$ 4,501.5
Number of reporting segments \| segment			4
Number of operating segments \| segment			4
General Corporate Expense
Segment Reporting Information [Line Items]
Operating income	(51.6)	(46.8)	$ (169.2)	(173.6)
Total assets	376.8		376.8		321.0
U.S. Information Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue	317.4	292.5	920.2	875.1
Operating income	139.5	117.0	396.3	368.1
Total assets	1,842.7		1,842.7		1,869.6
International \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue	214.3	145.4	591.2	425.9
Operating income	26.3	28.5	79.3	84.0
Total assets	3,053.0		3,053.0		844.5
Workforce Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue	171.3	139.0	528.7	434.0
Operating income	69.9	50.0	226.9	165.9
Total assets	1,345.2		1,345.2		1,268.5
Global Consumer Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue	101.1	90.5	303.7	262.3
Operating income	28.0	$ 25.6	80.7	$ 72.6
Total assets	$ 188.9		$ 188.9		$ 197.9

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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