SEGMENT INFORMATION (Operating Revenue and Operating Income by Operating Segment) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015 segment	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Operating revenue	$ 651.8us-gaap_SalesRevenueServicesNet	$ 584.5us-gaap_SalesRevenueServicesNet
Operating income	154.2us-gaap_OperatingIncomeLoss	151.9us-gaap_OperatingIncomeLoss
Total assets	4,595.0us-gaap_Assets		4,674.2us-gaap_Assets
Number of reportable segments	4us-gaap_NumberOfReportableSegments
U.S. Information Solutions
Segment Reporting Information [Line Items]
Operating revenue	298.7	261.2
Operating income	126.6	97.0
Total assets	1,972.9		1,983.9
International
Segment Reporting Information [Line Items]
Operating revenue	138.8	140.8
Operating income	28.0	29.0
Total assets	918.7		983.7
Workforce Solutions
Segment Reporting Information [Line Items]
Operating revenue	148.7	119.7
Operating income	60.0	38.7
Total assets	1,285.5		1,271.3
Personal Solutions
Segment Reporting Information [Line Items]
Operating revenue	65.6	62.8
Operating income	18.0	17.9
Total assets	119.3		123.8
General Corporate
Segment Reporting Information [Line Items]
Operating income	(78.4)	(30.7)
Total assets	$ 298.6		$ 311.5

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 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

-Section 02

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

+ 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=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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