SEGMENT INFORMATION (Operating Revenue and Operating Income by Operating Segment) (Detail) $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) segment	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Operating revenue:	$ 728.3	$ 651.8
Operating income:	176.2	154.2
Total assets:	$ 6,732.9		$ 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:	$ (71.6)	(78.4)
Total assets:	322.9		321.0
U.S. Information Solutions
Segment Reporting Information [Line Items]
Operating revenue:	294.9	284.5
Operating income:	122.8	123.1
Total assets:	1,858.9		1,869.6
International
Segment Reporting Information [Line Items]
Operating revenue:	158.1	135.4
Operating income:	19.4	27.1
Total assets:	3,057.1		844.5
Workforce Solutions
Segment Reporting Information [Line Items]
Operating revenue:	180.1	148.7
Operating income:	78.6	60.0
Total assets:	1,292.6		1,268.5
Global Consumer Solutions
Segment Reporting Information [Line Items]
Operating revenue:	95.2	83.2
Operating income:	27.0	$ 22.4
Total assets:	$ 201.4		$ 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))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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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