SEGMENT INFORMATION (Operating Revenue and Operating Income by Operating Segment) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) segment	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Operating revenue:	$ 811.3	$ 678.1	$ 1,539.6	$ 1,329.9
Operating income:	225.7	188.5	401.9	342.7
Total assets:	6,640.8		$ 6,640.8		$ 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:	(46.1)	(48.5)	$ (117.6)	(126.9)
Total assets:	364.2		364.2		321.0
U.S. Information Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue:	307.9	298.2	602.8	582.7
Operating income:	134.0	128.0	256.8	251.1
Total assets:	1,846.0		1,846.0		1,869.6
International \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue:	218.8	145.1	376.9	280.5
Operating income:	33.7	28.5	53.0	55.6
Total assets:	2,958.8		2,958.8		844.5
Workforce Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue:	177.3	146.3	357.4	295.0
Operating income:	78.3	56.0	156.9	116.0
Total assets:	1,275.0		1,275.0		1,268.5
Global Consumer Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue:	107.3	88.5	202.5	171.7
Operating income:	25.8	$ 24.5	52.8	$ 46.9
Total assets:	$ 196.8		$ 196.8		$ 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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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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